Greg Jordan

Letting giants be – rethinking active fire management of old‐growth eucalypt forest in the Australian tropics

Publisher: Wiley

Date: 24-03-2014

DOI: 10.1111/1365-2664.12233

Testing the Biases in the Rich Cenozoic Angiosperm Macrofossil Record

Publisher: University of Chicago Press

Date: 05-2016

DOI: 10.1086/685388

Key periods in the evolution of the flora and vegetation in Western Tasmania I. The early-middle pleistocene

Publisher: CSIRO Publishing

Date: 1993

DOI: 10.1071/BT9930673

Abstract: The relatively simple flora and structure of Nothofagus cunninghamii cool temperate rainforest in Tasmania is widely accepted to be the result of repeated glaciation during the Pleistocene. Plant macrofossils, spores and pollen preserved at Regatta Point, western Tasmania, indicate that several gymnosperms and subcanopy angiosperms with warm temperate affinities had survived one to several episodes of cold, possibly glacial climates, before becoming extinct in the early to middle Pleistocene: Callitris/Actinostrobus, Dacrycarpus, Austromyrtus, Eucalyptus spathulata-type, Haloragodendron-type, Loranthaceae, Quintinia and Symplocos. These co-existed in Nothofagus-Lagarostroboss franklinii rainforest with a number of taxa that are now restricted to upper subalpine-alpine habitats in Tasmania, such as Astelia, Gunnera and Microcachrys. The community is difficult to interpret in terms of modem species and we propose that either extinct taxa are being concealed by essentially modern pollen morphologies, that ecological preferences have altered since the early-middle Pleistocene, or both. Patterns of extinctions in Tasmania (and New Zealand) suggest that Pleistocene climatic change at middle-high latitudes presented an environmental stress not previously experienced during the Cenozoic, perhaps through widespread periglacial conditions, but also provided ecological and evolutionary opportunities for rainforest species tolerant of a wide range of conditions experienced during the late Pleistocene.

Linking changes in community composition and function under climate change

Publisher: Wiley

Date: 12-2015

DOI: 10.1890/14-2384.1

Abstract: Climate change is expected to directly alter the composition of communities and the functioning of ecosystems across the globe. Improving our understanding of links between bio ersity and ecosystem functioning across large spatial scales and rapid global change is a major priority to help identify management responses that will retain erse, functioning systems. Here we address this challenge by linking projected changes in plant community composition and functional attributes (height, leaf area, seed mass) under climate change across Tasmania, Australia. Using correlative community-level modeling, we found that projected changes in plant community composition were not consistently related to projected changes in community mean trait values. In contrast, we identified specific mechanisms through which alternative combinations of projected functional and compositional change across Tasmania could be realized, including loss/replacement of functionally similar species (lowland grasslands/grassy woodlands) and loss of a small number of functionally unique species (lowland forests). Importantly, we demonstrate how these linked projections of change in community composition and functional attributes can be utilized to inform specific management actions that may assist in maintaining erse, functioning ecosystems under climate change.

Oligocene leaves of epacridaceae from little rapid river, tasmania, and theidentification of fossil epacridaceae leaves

Publisher: CSIRO Publishing

Date: 1995

DOI: 10.1071/SB9950071

Abstract: The leaves of most Epacridaceae have distinctive combinations of shape, venation and cuticular morphology. Some groups of genera, but few genera or species, also have distinctive combinations of leaf traits. Two new genera, Epacriphyllum and Richeaphyllum, are proposed for fossil leaves which can be clearly attributed to tribe Epacrideae and subfamily Richeoideae respectively, but cannot be assigned to extant genera due to lack of information. Two new species of Epacriphyllum and one of Richeaphyllum are proposed from Oligocene sediments at Little Rapid River, western Tasmania. Leaves which are probably of the tribe Styphelieae also occur in these sediments. These are the earliest macrofossil records of the family, and confirm that two large phylogenetic groups within the family had differentiated by this time. A key to groups of epacridaceous genera is given to assist the identification of fossil leaves.

Succession of mosses, liverworts and ferns on coarse woody debris, in relation to forest age and log decay in Tasmanian wet eucalypt forest

Publisher: Elsevier BV

Date: 10-2010

DOI: 10.1016/J.FORECO.2010.08.038

Leaf Maximum Photosynthetic Rate and Venation Are Linked by Hydraulics

Publisher: Oxford University Press (OUP)

Date: 07-06-2007

DOI: 10.1104/PP.107.101352

Abstract: Leaf veins are almost ubiquitous across the range of terrestrial plant ersity, yet their influence on leaf photosynthetic performance remains uncertain. We show here that specific physical attributes of the vascular plumbing network are key limiters of the hydraulic and photosynthetic proficiency of any leaf. Following the logic that leaf veins evolved to bypass inefficient water transport through living mesophyll tissue, we examined the hydraulic pathway beyond the distal ends of the vein system as a possible limiter of water transport in leaves. We tested a mechanistic hypothesis that the length of this final traverse, as water moves from veins across the mesophyll to where it evaporates from the leaf, governs the hydraulic efficiency and photosynthetic carbon assimilation of any leaf. S ling 43 species across the breadth of plant ersity from mosses to flowering plants, we found that the post-vein traverse as determined by characters such as vein density, leaf thickness, and cell shape, was strongly correlated with the hydraulic conductivity and maximum photosynthetic rate of foliage. The shape of this correlation provided clear support for the a priori hypothesis that vein positioning limits photosynthesis via its influence on leaf hydraulic efficiency.

Diverse fossil epacrids (Styphelioideae; Ericaceae) from early pleistocene sediments at Stony Creek Basin, Victoria, Australia

Publisher: University of Chicago Press

Date: 11-2007

DOI: 10.1086/521686

Evolution of stomatal responsiveness to CO₂ and optimization of water‐use efficiency among land plants

Publisher: Wiley

Date: 17-07-2009

DOI: 10.1111/J.1469-8137.2009.02844.X

Abstract: The stomata of angiosperms respond to changes in ambient atmospheric concentrations of CO(2) (C(a)) in ways that appear to optimize water-use efficiency. It is unknown where in the history of land plants this important stomatal control mechanism evolved. Here, we test the hypothesis that major clades of plants have distinct stomatal sensitivities to C(a) reflecting a relatively recent evolution of water-use optimization in derived angiosperms. Responses of stomatal conductance (g(s)) to step changes between elevated, ambient and low C(a) (600, 380 and 100 micromol mol(-1), respectively) were compared in a phylogenetically and ecologically erse range of higher angiosperms, conifers, ferns and lycopods. All species responded to low C(a) by increasing g(s) but only angiosperm stomata demonstrated a significant closing response when C(a) was elevated to 600 micromol mol(-1). As a result, angiosperms showed significantly greater increases in water-use efficiency under elevated C(a) than the other lineages. The data suggest that the angiosperms have mechanisms for detecting and responding to increases in C(a) that are absent from earlier erging lineages, and these mechanisms impart a greater capacity to optimize water-use efficiency.

Chloroplast evidence for geographic stasis of the Australian bird-dispersed shrub Tasmannia lanceolata (Winteraceae)

Publisher: Wiley

Date: 07-2010

DOI: 10.1111/J.1365-294X.2010.04725.X

Incontinence in aging leaves: deteriorating water relations with leaf age in Agastachys odorata (Proteaceae), a shrub with very long-lived leaves

Publisher: CSIRO Publishing

Date: 2007

DOI: 10.1071/FP07166

Abstract: This paper examines physiological characteristics of the leaves of Agastachys odorata R.Br., a wet-climate sclerophyllous shrub with very long-lived leaves. It addresses the hypothesis that cuticles become leakier to water vapour as leaves age. Astomatous cuticular conductance, whole-leaf minimum epidermal conductance, leaf damage and accumulation of epiphylls all increased several-fold with leaf age from first year growth to 10 years of age. Maximum carbon assimilation peaked 1 year after full leaf expansion, then declined. Intrinsic water use efficiency was highest in mid-aged leaves and declined markedly in the oldest leaves. Stomatal density, stomatal size and cuticle thickness did not vary significantly among ages. The older leaves were less effective at controlling water loss, resulting in decreases in water use efficiency. A differential increase in the conductance of the stomatal surface of the leaves relative to astomatous surface suggested that stomatal leakiness was significant in leaves over five years old. Although data for other species is ambiguous, the deterioration in A. odorata appears to be consistent with changes in the oldest leaves of other species. Thus, decreasing ability to use water efficiently appears to be a consequence of accumulated damage and may contribute to the need for leaf senescence in evergreen species with little self shading.

Water supply and demand remain balanced during leaf acclimation of Nothofagus cunninghamii trees

Publisher: Wiley

Date: 16-06-2011

DOI: 10.1111/J.1469-8137.2011.03795.X

Abstract: Higher leaf vein density (D(vein) ) enables higher rates of photosynthesis because enhanced water transport allows higher leaf conductances to CO(2) and water. If the total cost of leaf venation rises in proportion to the density of minor veins, the most efficient investment in leaf xylem relative to photosynthetic gain should occur when the water transport capacity of the leaf (determined by D(vein) ) matches potential transpirational demand (determined by stomatal size and density). We tested whether environmental plasticity in stomatal density (D(stomata) ) and D(vein) were linked in the evergreen tree Nothofagus cunninghamii to achieve a balance between liquid and gas phase water conductances. Two sources of variation were examined within-tree light acclimation, and differences in sun leaves among plants from ecologically erse populations. Strong, linear correlations between D(vein) and D(stomata) were found at all levels of comparison. The correlations between liquid- and vapour-phase conductances implied by these patterns of leaf anatomy were confirmed by direct measurement of leaf conductance in sun and shade foliage of an in idual tree. • Our results provide strong evidence that the development of veins and stomata are coordinated so that photosynthetic yield is optimized relative to carbon investment in leaf venation.

Microclimate through space and time: Microclimatic variation at the edge of regeneration forests over daily, yearly and decadal time scales

Publisher: Elsevier BV

Date: 12-2014

DOI: 10.1016/J.FORECO.2014.09.008

Late Pleistocene Vegetation and Climate Near Melaleuca Inlet, South-Western Tasmania

Publisher: CSIRO Publishing

Date: 1991

DOI: 10.1071/BT9910315

Abstract: Macrofossils of 27 taxa and microfossils of 47 taxa are identified from a Late Pleistocene deposit at Melaleuca Inlet with a minimum age of 38 800 years. Interpretation of the fossil assemblage suggests that at the time of deposition the climate was cooler than at present and at least as wet. The local vegetation was dominated by wet scrub and sedgeland-heath communities with rainforest and wet sclerophyll forest also present. Species composition was similar to extant vegetation in the region but now-extinct species and possibly communities were present. Charcoal occurs in the sediments and the taxonomic make-up of the assemblage is consistent with the presence of a well established high fire frequency, despite the deposit pre-dating the earliest known human occupation of Tasmania.

Eocene continental climates and latitudinal temperature gradients: Comment and Reply

Publisher: Geological Society of America

Date: 1996

DOI: 10.1130/0091-7613(1996)024<1054:ECCALT>2.3.CO;2

Wheat leaves embolized by water stress do not recover function upon rewatering

Publisher: Wiley

Date: 24-08-2018

DOI: 10.1111/PCE.13397

Abstract: New techniques now make it possible to precisely and accurately determine the failure threshold of the plant vascular system during water stress. This creates an opportunity to understand the vulnerability of species to drought, but first, it must be determined whether damage to leaf function associated with xylem cavitation is reparable or permanent. This question is particularly relevant in crop plants such as wheat, which may have the capacity to repair xylem embolism with positive root pressure. Using wheat (Triticum aestivum, Heron), we employed non-invasive imaging to find the water potential causing 50% xylem embolism (-2.87 ± 0.52 MPa) in leaves. Replicate plants were water-stressed to varying degrees to induce embolism ranging from minimal to substantial. Plants were then rewatered to determine the reversibility of xylem damage and photosynthetic inhibition in glasshouse conditions. Rewatering after drought-induced xylem cavitation did not induce visible refilling of embolized xylem, and embolized leaves showed photosynthetic impairment upon rewatering. This impairment was significant even after only 10-20% of leaf veins were embolized, and leaves accumulating >20% embolism died upon rewatering in 7/10 in iduals. Photosynthetic damage and hydraulic decline occurred concurrently as wheat leaves dehydrated, and leaf shrinkage during drying was the best predictor of photosynthetic recovery.

Amphistomatic leaf surfaces independently regulate gas exchange in response to variations in evaporative demand

Publisher: Oxford University Press (OUP)

Date: 28-06-2017

DOI: 10.1093/TREEPHYS/TPX073

Abstract: The occurrence of histomatic leaves (stomata on both surfaces) versus hypostomatic leaves (stomata limited to the lower or abaxial surface) has strong associations with environment. Amphistomy provides the advantage of higher conductance of CO2 for photosynthesis, however, unless the stomata on both leaf surfaces can be independently controlled in response to environmental cues, histomy may lead to inefficient gas exchange. While previous studies have found evidence that stomata can operate independently across and between surfaces of dorsiventral leaves, we investigate whether an independent stomatal response can be induced for isobilateral leaves by largely natural conditions. Here, we exposed surfaces of isobilateral, histomatic Eucalyptus globulus Labill. leaves to natural diurnal variation in differential evaporative demand, using leaf orientation to drive differences in irradiance and heat load on leaf surfaces. We identified preferential closure of stomata on the surface exposed to higher irradiation (and therefore evaporative demand) during the afternoon under natural conditions and similarly induced differential stomatal closure under experimental conditions in the laboratory. The differential response confirms that sufficient hydraulic isolation exists for independent stomatal response to occur between surfaces of histomatic, isobilateral leaves, and importantly, we show that natural conditions can induce surface-specific stomatal closure.

How does ontogeny in a Eucalyptus species affect patterns of herbivory by Brushtail Possums?

Publisher: Wiley

Date: 18-09-2006

DOI: 10.1111/J.1365-2435.2006.01193.X

Why we should retain Nothofagus sensu lato

Publisher: CSIRO Publishing

Date: 2015

DOI: 10.1071/SB15026

Abstract: We present the case that the fossil record of Nothofagaceae, which is much more extensive in terms of species numbers than the living species, cannot be dealt with in a productive way by the recent proposal by Heenan and Smissen to split Nothofagus into four genera (Phytotaxa, vol. 146, 0.11646 hytotaxa.146.1.1). Such a proposal will render the fossil record almost unworkable, and will lead to a major split in the approach taken by palynologists in comparison to other researchers. We believe the case for the new generic names, while valid, is weak, and is far outweighed by the utility of retaining Nothofagus sensu lato.

Reproductive success of a colony of the introduced bumblebee Bombus terrestris (L.) (Hymenoptera: Apidae) in a Tasmanian National Park

Publisher: Wiley

Date: 05-2006

DOI: 10.1111/J.1440-6055.2006.00527.X

TRY plant trait database – enhanced coverage and open access

Publisher: Wiley

Date: 31-12-2019

DOI: 10.1111/GCB.14904

Abstract: Plant traits—the morphological, anatomical, physiological, biochemical and phenological characteristics of plants—determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to bio ersity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait‐based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits—almost complete coverage for ‘plant growth form’. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait–environmental relationships. These traits have to be measured on in idual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives.

Leaf fossils of Banksia (Proteaceae) from New Zealand: An Australian abroad

Publisher: Wiley

Date: 02-2010

DOI: 10.3732/AJB.0900199

Abstract: Fossils can shed new light on plant biogeography and phylogeny. Pinnately lobed leaves from the Oligo-Miocene Newvale lignite mine, South Island, New Zealand are the first extra-Australian leaf fossils of the charismatic genus Banksia (Proteaceae), and they are assigned to a new species, B. novae-zelandiae. Comparison with extant taxa shows that the fossils are best regarded as an extinct stem relative of Banksia because their available features are either plesiomorphic for the genus (notably, the stomata are superficially placed, not sunken in balloon-like pits as in many extant species) or lack evidence of synapomorphies that would enable them to be placed in the crown group. Banksia novae-zelandiae does, however, exhibit two cuticular features that are unique or highly derived for Banksia. These are rugulate subsidiary cell ornamentation and the presence of complex papillae that extensively cover the abaxial leaf surface. The fossils add to the widespread records of the pinnately lobed leaf form in Banksia in Australia beginning in the late Paleocene. This form is now limited to species confined to sclerophyllous heathlands of Mediterranean climate in southwestern Australia. Banksia novae-zelandiae could be part of a lineage that had a long history in New Zealand, perhaps dating to the early Paleogene.

A critical framework for the assessment of biological palaeoproxies: predicting past climate and levels of atmospheric CO₂ from fossil leaves

Publisher: Wiley

Date: 19-07-2011

DOI: 10.1111/J.1469-8137.2011.03829.X

Abstract: This review uses proxies of past temperature and atmospheric CO 2 composition based on fossil leaves to illustrate the uncertainties in biologically based proxies of past environments. Most leaf‐based proxies are geographically local or genetically restricted and therefore can be confounded by evolution, extinction, changes in local environment or immigration of species. Stomatal frequency proxies illustrate how genetically restricted proxies can be particularly vulnerable to evolutionary change. High predictive power in the modern world resulting from the use of a very narrow calibration cannot be confidently extrapolated into the past (the Ginkgo paradox). Many foliar physiognomic proxies of climate are geographically local and use traits that are more or less fixed for in idual species. Such proxies can therefore be confounded by floristic turnover and biome shifts in the region of calibration. Uncertainty in proxies tends to be greater for more ancient fossils. I present a set of questions that should be considered before using a proxy. Good proxies should be relatively protected from environmental and genetic change, particularly through having high information content and being founded on biomechanical or biochemical principles. Some current and potential developments are discussed, including those that involve more mechanistically sound proxies and better use of multivariate approaches. Contents Summary 29 I. Introduction 30 II. Key concepts in the uncertainty of proxy evidence 30 III. Uncertainties in major foliar physiognomic proxies of MAT 31 IV. Stomatal density and stomatal index 34 V. Steps forward 38 VI. Synthesis 40 Acknowledgements 40 References 40

Last interglacial climates of south-eastern Australia: plant and beetle-based reconstructions from Yarra Creek, King Island, Tasmania

Publisher: Elsevier BV

Date: 12-2009

DOI: 10.1016/J.QUASCIREV.2009.09.023

Fire is a major driver of patterns of genetic diversity in two co‐occurring Tasmanian palaeoendemic conifers

Publisher: Wiley

Date: 02-12-2016

DOI: 10.1111/JBI.12919

Using fossil leaves as evidence for open vegetation

Publisher: Elsevier BV

Date: 02-2014

DOI: 10.1016/J.PALAEO.2013.12.035

Is there a ‘suboptimal’ woody species height? A response to Scheffer et al.

Publisher: Elsevier BV

Date: 2015

DOI: 10.1016/J.TREE.2014.09.007

Cenozoic vegetation in Tasmania: macrofossil evidence

Publisher: University of Adelaide Press

Date: 30-03-2017

DOI: 10.20851/AUSTRALIAN-VEGETATION-12

Distinctive Arbutin‐Containing Markers: Chemotaxonomic Significance and Insights Into the Evolution of Proteaceae Phytochemistry

Publisher: Wiley

Date: 13-10-2023

DOI: 10.1002/CBDV.202301112

Development of nuclear and mitochondrial microsatellite markers for the relictual conifer genus Athrotaxis (Cupressaceae)

Publisher: Springer Science and Business Media LLC

Date: 07-12-2014

DOI: 10.1007/S12686-014-0400-8

Stable states in soil chemistry persist in eucalypt woodland restorations

Publisher: Wiley

Date: 11-11-2018

DOI: 10.1111/AVSC.12404

Drought tolerance and avoidance in the localised endemic leptospermum grandiflorum and co-occurring species

Publisher: CSIRO Publishing

Date: 1993

DOI: 10.1071/SB9930559

Abstract: A physiological case study of the genus Leptospermum is used to highlight the importance of the historical effects of the dry Last Glacial (30 000–15 000 BP) on current plant distributions in Tasmania. The water relations of the endemic L. grandiforum Lodd., which has a restricted distribution, is contrasted with three widespread taxa of this genus. The results suggest that L. grandiflorum is better suited for survival in dry areas, to which its distribution is restricted, than the more widespread species. Leptospermum grandiflorum is also shown to have a slower growth rate under moist conditions than the widespread taxa, which perhaps explains its apparent lack of dispersal during the moister interglacial. Thus, historical factors are likely to be the cause of the restricted distribution of this localised endemic to small areas of the east coast of Tasmania.

Testing the Impact of Calibration on Molecular Divergence Times Using a Fossil-Rich Group: The Case of Nothofagus (Fagales)

Publisher: Oxford University Press (OUP)

Date: 26-12-2011

DOI: 10.1093/SYSBIO/SYR116

Abstract: Although temporal calibration is widely recognized as critical for obtaining accurate ergence-time estimates using molecular dating methods, few studies have evaluated the variation resulting from different calibration strategies. Depending on the information available, researchers have often used primary calibrations from the fossil record or secondary calibrations from previous molecular dating studies. In analyses of flowering plants, primary calibration data can be obtained from macro- and mesofossils (e.g., leaves, flowers, and fruits) or microfossils (e.g., pollen). Fossil data can vary substantially in accuracy and precision, presenting a difficult choice when selecting appropriate calibrations. Here, we test the impact of eight plausible calibration scenarios for Nothofagus (Nothofagaceae, Fagales), a plant genus with a particularly rich and well-studied fossil record. To do so, we reviewed the phylogenetic placement and geochronology of 38 fossil taxa of Nothofagus and other Fagales, and we identified minimum age constraints for up to 18 nodes of the phylogeny of Fagales. Molecular dating analyses were conducted for each scenario using maximum likelihood (RAxML + r8s) and Bayesian (BEAST) approaches on sequence data from six regions of the chloroplast and nuclear genomes. Using either ingroup or outgroup constraints, or both, led to similar age estimates, except near strongly influential calibration nodes. Using "early but risky" fossil constraints in addition to "safe but late" constraints, or using assumptions of vicariance instead of fossil constraints, led to older age estimates. In contrast, using secondary calibration points yielded drastically younger age estimates. This empirical study highlights the critical influence of calibration on molecular dating analyses. Even in a best-case situation, with many thoroughly vetted fossils available, substantial uncertainties can remain in the estimates of ergence times. For ex le, our estimates for the crown group age of Nothofagus varied from 13 to 113 Ma across our full range of calibration scenarios. We suggest that increased background research should be made at all stages of the calibration process to reduce errors wherever possible, from verifying the geochronological data on the fossils to critical reassessment of their phylogenetic position.

Epiphytic ferns and bryophytes of Tasmanian tree-ferns: A comparison of diversity and composition between two host species

Publisher: Wiley

Date: 04-2005

DOI: 10.1111/J.1442-9993.2005.01440.X

Leaf hydraulic conductance is linked to leaf symmetry in bifacial, amphistomatic leaves of sunflower

Publisher: Oxford University Press (OUP)

Date: 23-01-2020

DOI: 10.1093/JXB/ERAA035

Abstract: The hydraulic implications of stomatal positioning across leaf surfaces and the impact on internal water flow through histomatic leaves are not currently well understood. Amphistomaty potentially provides hydraulic efficiencies if the majority of hydraulic resistance in the leaf exists outside the xylem in the mesophyll. Such a scenario would mean that the same xylem network could equally supply a hypostomatic or histomatic leaf. Here we examine leaves of Helianthus annuus to determine whether histomaty in this species is associated with higher hydraulic efficiency compared with hypostomatic leaves. We identified asymmetry in the positioning of minor veins which were significantly closer to the abaxial than the adaxial leaf surface, combined with lower Kleaf when transpiration was driven through the adaxial rather than the abaxial surface. We also identified a degree of coordination in stomatal behaviour driven by leaf hydraulics, where the hydraulic conditions experienced by an in idual leaf surface affected the stomatal behaviour on the opposite surface. We found no advantage to histomaty based on efficiencies in construction costs of the venous system, represented by vein density:stomatal density, only limited hydraulic independence between leaf surfaces. These results suggest that histomaty does not substantially increase whole-leaf hydraulic efficiency.

Acclimation to humidity modifies the link between leaf size and the density of veins and stomata

Publisher: Wiley

Date: 10-06-2013

DOI: 10.1111/PCE.12136

Abstract: The coordination of veins and stomata during leaf acclimation to sun and shade can be facilitated by differential epidermal cell expansion so large leaves with low vein and stomatal densities grow in shade, effectively balancing liquid- and vapour-phase conductances. As the difference in vapour pressure between leaf and atmosphere (VPD) determines transpiration at any given stomatal density, we predict that plants grown under high VPD will modify the balance between veins and stomata to accommodate greater maximum transpiration. Thus, we examined the developmental responses of these traits to contrasting VPD in a woody angiosperm (Toona ciliata M. Roem.) and tested whether the relationship between them was altered. High VPD leaves were one-third the size of low VPD leaves with only marginally greater vein and stomatal density. Transpirational homeostasis was thus maintained by reducing stomatal conductance. VPD acclimation changed leaf size by modifying cell number. Hence, plasticity in vein and stomatal density appears to be generated by plasticity in cell size rather than cell number. Thus, VPD affects cell number and leaf size without changing the relationship between liquid- and vapour-phase conductances. This results in inefficient acclimation to VPD as stomata remain partially closed under high VPD.

Giant eucalypts – globally unique fire‐adapted rain‐forest trees?

Publisher: Wiley

Date: 11-2012

DOI: 10.1111/J.1469-8137.2012.04359.X

Abstract: Tree species exceeding 70 m in height are rare globally. Giant gymnosperms are concentrated near the Pacific coast of the USA , while the tallest angiosperms are eucalypts ( E ucalyptus spp.) in southern and eastern Australia. Giant eucalypts co‐occur with rain‐forest trees in eastern Australia, creating unique vegetation communities comprising fire‐dependent trees above fire‐intolerant rain‐forest. However, giant eucalypts can also tower over shrubby understoreys (e.g. in Western Australia). The local abundance of giant eucalypts is controlled by interactions between fire activity and landscape setting. Giant eucalypts have features that increase flammability (e.g. oil‐rich foliage and open crowns) relative to other rain‐forest trees but it is debatable if these features are adaptations. Probable drivers of eucalypt gigantism are intense intra‐specific competition following severe fires, and inter‐specific competition among adult trees. However, we suggest that this was made possible by a general capacity of eucalypts for ‘hyper‐emergence’. We argue that, because giant eucalypts occur in rain‐forest climates and share traits with rain‐forest pioneers, they should be regarded as long‐lived rain‐forest pioneers, albeit with a particular dependence on fire for regeneration. These unique ecosystems are of high conservation value, following substantial clearing and logging over 150 yr. Contents Summary 1001 I. Introduction 1001 II. Giant eucalypts in a global context 1002 III. Giant eucalypts – taxonomy and distribution 1004 IV. Growth of giant eucalypts 1006 V. Fire and regeneration of giant eucalypts 1008 VI. Are giant eucalypts different from other rain‐forest trees? 1009 VII. Conclusions 1010 Acknowledgements 1011 References 1011

Deep history of wildfire in Australia

Publisher: CSIRO Publishing

Date: 2016

DOI: 10.1071/BT16169

Abstract: Australian plant species vary markedly in their fire responses, and the evolutionary histories of the erse range of traits that lead to fire tolerance and fire dependence almost certainly involves both exaptation and traits that evolved directly in response to fire. The hypothesis that very long-term nutrient poverty in Australian soils led to intense fires explains many of the unusual responses to fire by Australian species, as does near global distribution of evidence for fire during the Cretaceous, possibly driven by high atmospheric oxygen concentration. Recent descriptions of leaf fragments from a Late Cretaceous locality in central Australia have provided the first fossil evidence for ancient and possibly ancestral fire ecology in modern fire-dependent Australian clades, as suggested by some phylogenetic studies. The drying of the Australian climate in the Neogene allowed the rise to dominance of taxa that had their origin in the Late Cretaceous, but had not been prominent in the rainforest-dominated Paleogene. The Neogene climatic evolution meant that fire became an important feature of that environment and fire frequency and intensity began to grow to high levels, and many fire adaptations evolved. However, many plant species were already in place to take advantage of this new fire regime, and even though the original drivers for fire may have changed (possibly from high atmospheric oxygen concentrations, to long, hot, dry periods at different times in different parts of the continent), the adaptations that these species had for fire tolerance meant they could become prominent over much of the Australian continent by the time human colonisation began.

Tertiary and Quaternary fossil wood from Kerguelen (southern Indian Ocean),Bois fossiles tertiares et quaternaires de Kerguelen (ocean Indien austral)

Publisher: Elsevier BV

Date: 06-1998

DOI: 10.1016/S1251-8050(98)80030-X

Extent and timing of floristic exchange between Australian and Asian rain forests

Publisher: Wiley

Date: 17-05-2011

DOI: 10.1111/J.1365-2699.2011.02519.X

Early Eocene Ripogonum (Liliales: Ripogonaceae) leaf macrofossils from southern Australia

Publisher: CSIRO Publishing

Date: 2009

DOI: 10.1071/SB08050

Abstract: We present evidence that fossil leaves from an early Eocene estuarine mudstone deposit at Lowana Road in western Tasmania include the oldest records of the extant monocot genus, Ripogonum (Ripogonaceae). These fossils are similar to the extant eastern Australian and Papua New Guinean R. album R.Br. and New Zealand R. scandens J.R. et G.Forst., and are described as a new species, R. tasmanicum Conran, R.J.Carp. & G.J.Jord. The venation, cuticular and other leaf features of this fossil are included in a morphology-based phylogenetic analysis for the genus, and character evolution is discussed in relation to the ecology of the extant species and the palaeoenvironments of known Ripogonaceae fossil sites. The fossil (albeit on leaf characters) was placed close to the base of a black-fruited, Australian endemic Ripogonum clade. This suggests that the family have a long and conservative evolutionary history in association with moist forests, with the fossil locality showing palaeoclimate similar to the environments that most Ripogonum species still occupy today.

No cell is an island: characterising the leaf epidermis using epidermalmorph, a new R package

Publisher: Wiley

Date: 15-11-2023

DOI: 10.1111/NPH.18519

Abstract: The leaf epidermis is the interface between a plant and its environment. The epidermis is highly variable in morphology, with links to both phylogeny and environment, and this ersity is relevant to several fields, including physiology, functional traits, palaeobotany, taxonomy and developmental biology. Describing and measuring leaf epidermal traits remains challenging. Current approaches are either extremely labour‐intensive and not feasible for large studies or limited to measurements of in idual cells. Here, we present a method to characterise in idual cell size, shape (including the effect of neighbouring cells) and arrangement from light microscope images. We provide the first automated characterisation of cell arrangement (from traced images) as well as multiple new shape characteristics. We have implemented this method in an R package, epidermalmorph, and provide an ex le workflow using this package, which includes functions to evaluate trait reliability and optimal s ling effort for any given group of plants. We demonstrate that our new metrics of cell shape are independent of gross cell shape, unlike existing metrics. epidermalmorph provides a broadly applicable method for quantifying epidermal traits that we hope can be used to disentangle the fundamental relationships between form and function in the leaf epidermis.

Early ontogenetic trajectories vary among defence chemicals in seedlings of a fast-growing eucalypt

Publisher: Wiley

Date: 29-03-2010

DOI: 10.1111/J.1442-9993.2009.02021.X

Impacts on soils from cable-logging steep slopes in northeastern Tasmania, Australia

Publisher: Elsevier BV

Date: 04-2001

DOI: 10.1016/S0378-1127(00)00360-1

Using Multi-decadal Satellite Records to Identify Environmental Drivers of Fire Severity Across Vegetation Types

Publisher: Springer Science and Business Media LLC

Date: 07-07-2022

DOI: 10.1007/S41976-022-00070-9

Abstract: To date, most studies of fire severity, which is the ecological damage produced by a fire across all vegetation layers in an ecosystem, using remote sensing have focused on wildfires and forests, with less attention given to prescribed burns and treeless vegetation. Our research analyses a multi-decadal satellite record of fire severity in wildfires and prescribed burns, across forested and treeless vegetation, in western Tasmania, a wet region of frequent clouds. We used Landsat satellite images, fire history mapping and environmental predictor variables to understand what drives fire severity. Remotely-sensed fire severity was estimated by the Delta Normalised Burn Ratio (ΔNBR) for 57 wildfires and 70 prescribed burns spanning 25 years. Then, we used Random Forests to identify important predictors of fire severity, followed by generalised additive mixed models to test the statistical association between the predictors and fire severity. In the Random Forests analyses, mean summer precipitation, mean minimum monthly soil moisture and time since previous fire were important predictors in both forested and treeless vegetation, whereas mean annual precipitation was important in forests and temperature seasonality was important in treeless vegetation. Modelled ΔNBR (predicted ΔNBRs from the best-performing generalised additive mixed model) of wildfire forests was higher than modelled ΔNBR of prescribed burns. This study confirms that western Tasmania is a valuable pyrogeographical model for studying fire severity of wet ecosystems under climate change, and provides a framework to better understand the interactions between climate, fire severity and prescribed burning.

An investigation of long-distance dispersal based on species native to both Tasmania and New Zealand

Publisher: CSIRO Publishing

Date: 2001

DOI: 10.1071/BT00024

Abstract: Some 200 species of plants are currently recognised as being native to both Tasmania and New Zealand. It is argued that dispersal across the 1500–2000-km Tasman Sea has occurred in all of these species. Almost all (187) are herbs and constitute over 20% of the herbaceous flora of Tasmania. Common species, non-dioecious species, species with very small seeds, species from aquatic, coastal or wet habitats and possibly species with hooked fruit are all over-represented among the disjunct species of herbs. The incidence of disjunct species also varies significantly among families. In contrast, fleshy fruited species, or species with plumes or very hairy disseminules, are not over-represented among the herbaceous disjunct species. These data are used to model the probability that a species (past or present) with given traits would show a within-species trans-Tasman disjunction, and it is inferred that this can be used to give a crude approximation of the rates of long-distance dispersal for different types of species. The model can be tested by using molecular clock methods and could be made more robust by incorporating equivalent data from other disjunct regions.

Microsatellites for use in Nothofagus cunninghamii (Nothofagaceae) and related species

Publisher: Wiley

Date: 12-2004

DOI: 10.1046/J.1471-8286.2003.00558.X

Phylogenetic biome conservatism on a global scale

Publisher: Springer Science and Business Media LLC

Date: 15-02-2009

DOI: 10.1038/NATURE07764

Abstract: How and why organisms are distributed as they are has long intrigued evolutionary biologists. The tendency for species to retain their ancestral ecology has been demonstrated in distributions on local and regional scales, but the extent of ecological conservatism over tens of millions of years and across continents has not been assessed. Here we show that biome stasis at speciation has outweighed biome shifts by a ratio of more than 25:1, by inferring ancestral biomes for an ecologically erse s le of more than 11,000 plant species from around the Southern Hemisphere. Stasis was also prevalent in transocean colonizations. Availability of a suitable biome could have substantially influenced which lineages establish on more than one landmass, in addition to the influence of the rarity of the dispersal events themselves. Conversely, the taxonomic composition of biomes has probably been strongly influenced by the rarity of species' transitions between biomes. This study has implications for the future because if clades have inherently limited capacity to shift biomes, then their evolutionary potential could be strongly compromised by biome contraction as climate changes.

Transient hybridization, not homoploid hybrid speciation, between ancient and deeply divergent conifers

Publisher: Wiley

Date: 02-2016

DOI: 10.3732/AJB.1500433

Abstract: Homoploid hybrid speciation is receiving growing attention due the increasing recognition of its role in speciation. We investigate if in iduals intermediate in morphology between the two species of the conifer genus Athrotaxis represent a homoploid hybrid species, A. laxifolia, or are spontaneous F1 hybrids. A total of 1055 in iduals of Athrotaxis cupressoides and A. selaginoides, morphologically intermediate in iduals, and two putative hybrid swarms were s led across the range of the genus and genotyped with 13 microsatellites. We used simulations to test the power of our data to identify the pure species, F1s, F2s, and backcross generations. We found that Athrotaxis cupressoides and A. selaginoides are likely the most ergent congeneric conifers known, but the intermediates are F1 hybrids, sharing one allele each from A. cupressoides and A. selaginoides at six loci with completely species specific alleles. The hybrid swarms contain wide genetic variation with stronger affinities to the locally dominant species, A. selaginoides and A. selaginoides backcrosses outnumbering A. cupressoides backcrosses. In addition, we observed evidence for isolated advanced generation backcrosses within the range of the pure species. We conclude that, even though they can be large and long-lived, Athrotaxis hybrid swarms are on a trajectory of decline and will eventually be reabsorbed by the parental species. However, this process may take millennia and fossil evidence suggests that such events have occurred repeatedly since the early Quaternary. Given this timeline, our study highlights the many obstacles to homoploid hybrid speciation.

DNA metabarcoding captures subtle differences in forest beetle communities following disturbance

Publisher: Wiley

Date: 10-10-2020

DOI: 10.1111/REC.13236

Abstract: DNA metabarcoding is an emerging approach for monitoring bio ersity, but uncertainties remain about its capacity to detect subtle differences in invertebrate community composition comparable to those achievable based on conventional morphological identification. In this study, DNA metabarcoding and morphology‐based approaches were compared as tools for investigating whether logging history impacted beetle communities in Tasmanian wet eucalypt forests. We compared 12 unlogged mature forest sites with 12 neighboring regeneration sites that had been logged approximately 55 years previously. The number of species identified based on morphology (173) was close to the number of zero‐radius operational taxonomic units (ZOTUs) identified by DNA metabarcoding of cytochrome c oxidase subunit I (COI, 176) and 16S ribosomal RNA (16S, 156) markers. Subtle but significant differences in beetle species composition between regeneration and unlogged mature forests were captured by both morphology‐based and COI DNA metabarcoding approaches, but not by 16S DNA metabarcoding. Our results support the suitability of mitochondrial COI for studying invertebrate bio ersity. A slight loss of signal compared to the morphology‐based approach may be resolved by developing more comprehensive DNA reference databases. While confirming forest recovery of 48–58 years did not fully restore mature forest beetle communities, we suggest that DNA metabarcoding can be used for monitoring bio ersity and probing subtle differences in community composition.

Leaf fossils of Proteaceae tribe Persoonieae from the Late Oligocene - Early Miocene of New Zealand

Publisher: CSIRO Publishing

Date: 2010

DOI: 10.1071/SB09015

Abstract: Fossils from the Newvale lignite mine, Southland, are the first substantiated foliar records of Proteaceae subfamily Persoonioideae. The fossils possess very large stomata, a probable synapomorphy for Persoonioideae, and within Proteaceae the combination of this feature and more or less parallel-aligned, brachyparacytic stomatal complexes and undulate anticlinal epidermal cell walls is uniquely found in this subfamily. The new genus Persoonieaephyllum is described to recognise affinity of the fossil leaves and cuticles with tribe Persoonieae of Persoonioideae and their distinction from its only other extant representative, Placospermum. Two new species are described. P. ornatum is represented by linear leaves less than 20 mm wide and possessing more or less parallel-aligned major veins. These leaves closely match those of extant hypostomatic, broad-leaved species of tribe Persoonieae and are distinct from Placospermum in venation and several cuticular details. P. villosum has so far been recovered only as cuticular material in disaggregated lignite. It is distinct from P. ornatum in having abundant trichome bases, an absence of surface tubercules, and even larger stomata (guard cells often μm long). The fossils extend the known record of Persoonioideae in the New Zealand–New Caledonia region by ~20 million years.

Palaeoendemic plants provide evidence for persistence of open, well‐watered vegetation since the Cretaceous

Publisher: Wiley

Date: 10-11-2015

DOI: 10.1111/GEB.12389

The Cenozoic history of New Zealand temperate rainforests: comparisons with southern Australia and South America

Publisher: Informa UK Limited

Date: 02-04-2016

DOI: 10.1080/0028825X.2016.1144623

Convergent tip-to-base widening of water-conducting conduits in the tallest bryophytes

Publisher: Wiley

Date: 27-01-2022

DOI: 10.1002/AJB2.1795

Abstract: Tip‐to‐base conduit widening is considered a key mechanism that enables vascular plants to grow tall by decreasing the hydraulic resistance imposed by increasing height. Widening of hydraulic anatomy (larger conducting elements toward the base of the vascular system) minimizes gradients in leaf‐specific hydraulic conductance with plant height, allowing uniform photosynthesis across the crown of trees. Tip‐to‐base conduit widening has also been associated with changes in conduit number. However, in bryophytes, despite having representatives with internal water‐conducting tissue, conduit widening has been scarcely investigated. Here, we examined the changes in hydroid diameter and number with distance from plant tip in Dawsonia superba and D. polytrichoides , two representatives of the genus containing the tallest extant bryophytes. The position of these moss species on the global scale of conduit size and plant size was consistent with a general scaling among plants with internal water transport. Within plants, patterns of conduit widening and number with distance from plant tip in endohydric mosses were similar to those observed in vascular plants. This study demonstrated that land plants growing upward in the atmosphere show analogous conduit widening of hydraulic structures, suggesting that efficient internal water transport is a convergent adaptation for photosynthesis on land.

Short- and long-term benefits for forest biodiversity of retaining unlogged patches in harvested areas

Publisher: Elsevier BV

Date: 10-2015

DOI: 10.1016/J.FORECO.2015.05.021

Fossil leaf economics quantified: calibration, Eocene case study, and implications

Publisher: Cambridge University Press (CUP)

Date: 12-2007

DOI: 10.1666/07001.1

Temporal persistence of edge effects on bryophytes within harvested forests

Publisher: Elsevier BV

Date: 09-2016

DOI: 10.1016/J.FORECO.2016.05.044

Augmentation of abscisic acid (ABA) levels by drought does not induce short-term stomatal sensitivity to CO2 in two divergent conifer species

Publisher: Oxford University Press (OUP)

Date: 25-08-2010

DOI: 10.1093/JXB/ERQ260

Environmental adaptation in stomatal size independent of the effects of genome size

Publisher: Wiley

Date: 30-09-2014

DOI: 10.1111/NPH.13076

Abstract: Cell sizes are linked across multiple tissues, including stomata, and this variation is closely correlated with genome size. These associations raise the question of whether generic changes in cell size cause suboptimal changes in stomata, requiring subsequent evolution under selection for stomatal size. We tested the relationships among guard cell length, genome size and vegetation type using phylogenetically independent analyses on 67 species of the ecologically and structurally erse family, Proteaceae. We also compared how genome and stomatal sizes varied at ancient (among genera) and more recent (within genus) levels. The observed 60‐fold range in genome size in Proteaceae largely reflected the mean chromosome size. Compared with variation among genera, genome size varied much less within genera ( 6% of total variance) than stomatal size, implying evolution in stomatal size subsequent to changes in genome size. Open vegetation and closed forest had significantly different relationships between stomatal and genome sizes. Ancient changes in genome size clearly influenced stomatal size in Proteaceae, but adaptation to habitat strongly modified the genome–stomatal size relationship. Direct adaptation to the environment in stomatal size argues that new proxies for past concentrations of atmospheric CO 2 that incorporate stomatal size are superior to older models based solely on stomatal frequency.

Quantifying floristic and structural forest maturity: An attribute-based method for wet eucalypt forests

Publisher: Wiley

Date: 23-03-2018

DOI: 10.1111/1365-2664.13133

Susceptibility of Eucalyptus globulus ssp. globulus to sawfly (Perga affinis ssp. insularis) attack and its potential impact on plantation productivity

Publisher: Elsevier BV

Date: 05-2002

DOI: 10.1016/S0378-1127(01)00445-5

Unveiling the Complex Structure of Tasmanian Temperate Forests with Model-Based Tandem-X Tomography

Publisher: IEEE

Date: 07-2018

DOI: 10.1109/IGARSS.2018.8518350

The taphonomy of a remarkable leaf bed assemblage from the Late Oligocene–Early Miocene Gore Lignite Measures, southern New Zealand

Publisher: Elsevier BV

Date: 08-2010

DOI: 10.1016/J.COAL.2009.07.009

Fire in Australia: how was the biota prepared for human occupation?

Publisher: CSIRO Publishing

Date: 2016

DOI: 10.1071/BTV64N8_ED1

Early Tertiary Macrofossils of Proteaceae from Tasmania

Publisher: CSIRO Publishing

Date: 1997

DOI: 10.1071/SB96016

Abstract: Proteaceous leaves from two Early Tertiary sites in Tasmania are described and discussed. Based on gross leaf morphological and cuticular characters, 15 species are recognised from Oligocene lacustrine sediments at Cethana. Specimens of two taxa are not distinguishable from the extant species Telopea truncata from Tasmania and Lomatia fraxinifolia from north-eastern Queensland, and are therefore assigned to these species. Two new species of Banksieaephyllum are recognised. Ten other taxa are difficult to identify to existing genera, and are therefore referred to a new genus Proteaciphyllum. They all possess features typical of subfamily Grevilleoideae. Other, less well preserved, but probable Proteaceae from Cethana are also described. Specimens from the Leven River deposit, probably also of Oligocene age, are assigned to a new species of Orites, O. excelsoides. This species is closely related to extant O. excelsa from rainforests of north-eastern New South Wales and north-eastern Queensland. Cethana has by far the highest ersity of Proteaceae of any fossil flora described to date. The fossils also demonstrate the past association of now geographically remote taxa, and the prevalence of sclero- and xero-morphy in the family by the Oligocene.

Low but structured chloroplast diversity in Atherosperma moschatum (Atherospermataceae) suggests bottlenecks in response to the Pleistocene glacials

Publisher: Oxford University Press (OUP)

Date: 18-08-2011

DOI: 10.1093/AOB/MCR220

Unified changes in cell size permit coordinated leaf evolution

Publisher: Wiley

Date: 07-05-2013

DOI: 10.1111/NPH.12300

Abstract: The processes by which the functions of interdependent tissues are coordinated as lineages ersify are poorly understood. Here, we examine evolutionary coordination of vascular, epidermal and cortical leaf tissues in the anatomically, ecologically and morphologically erse woody plant family Proteaceae. We found that, across the phylogenetic range of Proteaceae, the sizes of guard, epidermal, palisade and xylem cells were positively correlated with each other but negatively associated with vein and stomatal densities. The link between venation and stomata resulted in a highly efficient match between potential maximum water loss (determined by stomatal conductance) and the leaf vascular system's capacity to replace that water. This important linkage is likely to be driven by stomatal size, because spatial limits in the packing of stomata onto the leaf surface apparently constrain the maximum size and density of stomata. We conclude that unified evolutionary changes in cell sizes of independent tissues, possibly mediated by changes in genome size, provide a means of substantially modifying leaf function while maintaining important functional links between leaf tissues. Our data also imply the presence of alternative evolutionary strategies involving cellular miniaturization during radiation into closed forest, and cell size increase in open habitats.

A paleobiogeographical scenario for the Taxaceae based on a revised fossil wood record and embolism resistance

Publisher: Elsevier BV

Date: 04-2019

DOI: 10.1016/J.REVPALBO.2019.01.003

Plant Traits Demonstrate That Temperate and Tropical Giant Eucalypt Forests Are Ecologically Convergent with Rainforest Not Savanna

Publisher: Public Library of Science (PLoS)

Date: 17-12-2013

DOI: 10.1371/JOURNAL.PONE.0084378

Mid Miocene–Last Interglacial Callitris (Cupressaceae) from south-eastern Australia

Publisher: Elsevier BV

Date: 04-2019

DOI: 10.1016/J.REVPALBO.2019.01.005

Differential leaf expansion can enable hydraulic acclimation to sun and shade

Publisher: Wiley

Date: 13-03-2012

DOI: 10.1111/J.1365-3040.2012.02498.X

Abstract: Although leaf size is one of the most responsive plant traits to environmental change, the functional benefits of large versus small leaves remain unclear. We hypothesized that modification of leaf size within species resulting from differences in irradiance can allow leaves to acclimate to different photosynthetic or evaporative conditions while maintaining an efficient balance between hydraulic supply (vein density) and evaporative demand. To test this, we compared the function and anatomy of leaf hydraulic systems in the leaves of a woody angiosperm (Toona ciliata M. Roem.) grown under high and low irradiance in controlled conditions. Our results confirm that in this species, differential leaf expansion regulates the density of veins and stomata such that leaf hydraulic conductance and stomatal conductance remain proportional. A broader s le of field-grown tree species suggested that differences in leaf venation and stomatal traits induced by sun and shade were not regulated by leaf size in all cases. Our results, however, suggest that leaf size plasticity can provide an efficient way for plants to acclimate hydraulic and stomatal conductances to the contrasting evaporative conditions of sun and shade.

The macrofossil record of Proteaceae in Tasmania: a review with new species

Publisher: CSIRO Publishing

Date: 1998

DOI: 10.1071/SB97020

Abstract: About 10 taxa of Proteaceae are known from the Early Eocene in Tasmania, onefrom a Late Eocene site, 22 from four Early Oligocene sites, one from a LateOligocene–Early Miocene site, 12 or 13 from two Early Pleistocene sites,and five or six from the Middle and Late Pleistocene. Most of the Tertiaryfossils are of extinct species, but the extant speciesLomatia fraxinifolia andTelopea truncata as well as apparent close relatives ofthe subalpine rainforest species Orites milliganii, andthe subtropical rainforest species O. excelsa have beenrecorded from the Early Oligocene. None of the Early Oligocene species areknown from more than one site, implying very high regional ersity, andfloristic differentiation among the sites. High ersity of Proteaceae atsome sites may be associated with oligotrophic soils. There is no evidence ofany of the modern species-rich scleromorphic groups of Proteaceae exceptBanksiinae. Scleromorphy was well established in Oriteae, Embothrieae andBanksiinae by the Early Oligocene. The Early Eocene fossils have very smallstomata, sparsely distributed on the leaf, which may have been due to elevatedatmospheric CO2. All extant Tasmanian genera and manyextant species as well as some extinct species were present by the EarlyPleistocene. The specific ersity within the region was probably higher thanit is now. In order to resolve a nomenclatural problem within the genusProteaciphyllum, EuproteaciphyllumG.J.Jord., R.J.Carp & R.S.Hill, gen. nov. is proposed and this name isapplied to 10 previously described species. The Tasmanian fossil taxa includethree new records, and nine new species:Euproteaciphyllum brookerensis G.J.Jord., R.J.Carp.& R.S.Hill, sp. nov., and E. tasmanicum G.J.Jord.,R.J.Carp. & R.S.Hill, sp. nov. from Early Eocene sediments andOrites milliganoides G.J.Jord., R.J.Carp. & R.S.Hill, sp. nov., O. scleromorpha G.J.Jord., R.J.Carp.& R.S.Hill, sp. nov., E. papillosumG.J.Jord.,R.J.Carp. & R.S.Hill, sp. nov., E. polymorphumG.J.Jord., R.J.Carp. & R.S.Hill, sp. nov.,E. microlobium G.J.Jord., R.J.Carp. & R.S.Hill, sp.nov., E. falcatum G.J.Jord., R.J.Carp. & R.S.Hill,sp. nov., and E. serratum G.J.Jord., R.J.Carp. & R.S.Hill, sp. nov. from Early Oligocene sediments.

Identifying regrowth forests with advanced mature forest values

Publisher: Elsevier BV

Date: 02-2019

DOI: 10.1016/J.FORECO.2018.10.048

Does moisture affect the partitioning of bryophytes between terrestrial and epiphytic substrates within cool temperate rain forests?

Publisher: American Bryological and Lichenological Society

Date: 09-2009

DOI: 10.1639/0007-2745-112.3.506

Development of nuclear microsatellite markers for the Tasmanian endemic conifer Diselma archeri Hook. F. (Cupressaceae)

Publisher: Springer Science and Business Media LLC

Date: 25-10-2014

DOI: 10.1007/S12686-014-0368-4

Strong, independent, quantitative genetic control of the timing of vegetative phase change and first flowering in Eucalyptus globulus ssp. globulus (Tasmanian Blue Gum)

Publisher: Springer Science and Business Media LLC

Date: 08-1999

DOI: 10.1046/J.1365-2540.1999.00570.X

Abstract: Analyses of large open-pollinated and controlled-cross field trials of Eucalyptus globulus ssp. globulus show quantitative genetic independence of the times of first flowering and the abrupt change in leaf form. The onset of each of these critical developmental events is under moderate to strong additive genetic control in this taxon, with in idual narrow-sense heritabilities of 0.4-0.6 and 0. 2-0.9, respectively, and little nonadditive genetic control. This strong additive genetic control and the independence of these processes provide the genetic environment for rapid heterochronic microevolution.

Fossil evidence for open, Proteaceae‐dominated heathlands and fire in the Late Cretaceous of Australia

Publisher: Wiley

Date: 12-2015

DOI: 10.3732/AJB.1500343

Abstract: The origin of biomes is of great interest globally. Molecular phylogenetic and pollen evidence suggest that several plant lineages that now characterize open, burnt habitats of the sclerophyll biome, became established during the Late Cretaceous of Australia. However, whether this biome itself dates to that time is problematic, fundamentally because of the near-absence of relevant, appropriately aged, terrestrial plant macro- or mesofossils. We recovered, identified, and interpreted the ecological significance of fossil pollen, foliar and other remains from a section of core drilled in central Australia, which we dated as Late C anian-Maastrichtian. The sediments contain plant fossils that indicate nutrient-limited, open, sclerophyllous vegetation and abundant charcoal as evidence of fire. Most interestingly, >30 pollen taxa and at least 12 foliage taxa are attributable to the important Gondwanan family Proteaceae, including several minute, histomatic, and sclerophyllous foliage forms consistent with subfamily Proteoideae. Microfossils, including an abundance of Sphagnales and other wetland taxa, provided strong evidence of a fenland setting. The local vegetation also included erse Ericaceae and Liliales, as well as a range of ferns and gymnosperms. The fossils provide strong evidence in support of hypotheses of great antiquity for fire and open vegetation in Australia, point to extraordinary persistence of Proteaceae that are now emblematic of the Mediterranean-type climate southwestern Australian bio ersity hotspot and raise the profile of open habitats as centers of ancient lineages.

Evolutionary Processes Shaping Postglacial Gene Pools of High-Altitude Forests: Evidence from the Endemic Eucalypts of Tasmania

Publisher: MDPI AG

Date: 23-05-2023

DOI: 10.3390/F14061072

Abstract: Climatic changes during the Pleistocene were responsible for dramatic redistributions of plant species worldwide. On the rugged southern hemisphere island of Tasmania, temperature increases following the last glaciation saw upslope migration of climatically suitable species from lowland refugia and the expansion of eucalypt-dominated forests and woodlands in the Central Highlands. We integrate multiple lines of evidence (chloroplast and nuclear DNA markers, seedling morphology, and survival in common garden experiments) from a group of closely related endemic eucalypts (the alpine white gums) to argue that (i) the Central Highlands of the island were colonised by multiple glacial refugia with hybridisation among species and previously separated populations, and (ii) natural selection has filtered the admixed populations, resulting in local adaptation to the harsh sub-alpine environment. Chloroplast haplotype ersity decreased and nuclear microsatellite ersity increased with altitude, chloroplast sharing among taxa was common, and nuclear DNA differentiation of morphologically distinct taxa was lower in the Central Highlands compared with lowland regions. Local adaptation in the highlands was signalled by evidence from (i) a glasshouse trial in which directional selection (QST FST) had shaped seedling morphological trait variation and (ii) population survival differences in 35-year-old reciprocal plantings along the major environmental gradients. We conclude that the evolutionary response of these island endemic trees to past climate change has involved the interplay of both hybridisation and natural selection, highlighting the importance of maintaining species interactions under future climate change.

Trophic position determines functional and phylogenetic recovery after disturbance within a community

Publisher: Wiley

Date: 29-03-2017

DOI: 10.1111/1365-2435.12845

The impacts of leaf shape and arrangement on light interception and potential photosynthesis in southern beech (Nothofagus cunninghamii)

Publisher: CSIRO Publishing

Date: 2004

DOI: 10.1071/FP03211

Abstract: The impact of differences in leaf shape, size and arrangement on the efficiency of light interception, and in particular the avoidance of photoinhibition, are poorly understood. We therefore estimated light exposure of branches in the cool temperate rainforest tree, Nothofagus cunninghamii (Hook.) Oerst., in which leaf shape, size and arrangement vary systematically with altitude and geographic origin. Measurements of incident photosynthetic photon flux density (PPFD) were made in the laboratory at solar angles corresponding to noon at summer solstice, winter solstice and equinox on branches collected from a common garden experiment. Tasmanian plants showed more self-shading than Victorian plants in summer and equinox. This was related to branch angle, leaf arrangement and leaf shape. Using a modelled light response-curve, we estimated the carbon assimilation rate and the flux density of excess photons at different incident PPFD. Victorian plants had higher predicted assimilation rates than Tasmanian plants in summer and equinox, but were exposed to substantially greater levels of excess photons. Because of the shape of the light-response curve, self-shading appears to reduce the plant's exposure to excess photons, thus providing photoprotection, without substantially reducing the carbon assimilation rate. This is dependent on both regional origin and season.

Relationships between coarse woody debris habitat quality and forest maturity attributes

Publisher: Wiley

Date: 28-06-2019

DOI: 10.1111/CSP2.55

Moving beyond the guild concept: developing a practical functional trait framework for terrestrial beetles

Publisher: Wiley

Date: 27-10-2014

DOI: 10.1111/EEN.12158

Macrofossils associated with the fossil fern spore Cyatheacidites annulatus and their significance for Southern hemisphere biogeography

Publisher: Elsevier BV

Date: 09-2001

DOI: 10.1016/S0034-6667(01)00088-4

Two new Banksia species from pleistocene sediments in western Tasmania

Publisher: CSIRO Publishing

Date: 1991

DOI: 10.1071/SB9910499

Abstract: Subtribe Banksiinae of the Proteaceae was erse in Tasmania in the early and middle Tertiary, but is now restricted to two species, Banksia marginata and B. serrata. Rapid and extreme environmental changes during the Pleistocene are likely causes of the extinction of some Banksia species in Tasmania. Such extinctions may have been common in many taxonomic groups. The leaves and infructescences of Banksia kingii Jordan & Hill, sp. nov. are described from late Pleistocene sediments. This is the most recent macrofossil record of a now extinct species in Tasmania. Banksia kingii is related to the extant B. saxicola. Banksia strahanensis Jordan & Hill, sp. nov. (known only from a leaf and leaf fragments and related to B. spinulosa) is described from Early to Middle Pleistocene sediments in Tasmania. This represents the third Pleistocene macrofossil record of a plant species which is now extinct in Tasmania.

Paleo‐Antarctic rainforest into the modern Old World tropics: The rich past and threatened future of the “southern wet forest survivors”

Publisher: Wiley

Date: 12-2014

DOI: 10.3732/AJB.1400340

Abstract: • Have Gondwanan rainforest floral associations survived? Where do they occur today? Have they survived continuously in particular locations? How significant is their living floristic signal? We revisit these classic questions in light of significant recent increases in relevant paleobotanical data.• We traced the extinction and persistence of lineages and associations through the past across four now separated regions-Australia, New Zealand, Patagonia, and Antarctica-using fossil occurrence data from 63 well-dated Gondwanan rainforest sites and 396 constituent taxa. Fossil sites were allocated to four age groups: Cretaceous, Paleocene-Eocene, Neogene plus Oligocene, and Pleistocene. We compared the modern and ancient distributions of lineages represented in the fossil record to see if dissimilarity increased with time. We quantified similarity-dissimilarity of composition and taxonomic structure among fossil assemblages, and between fossil and modern assemblages.• Strong similarities between ancient Patagonia and Australia confirmed shared Gondwanan rainforest history, but more of the lineages persisted in Australia. S les of ancient Australia grouped with the extant floras of Australia, New Guinea, New Caledonia, Fiji, and Mt. Kinabalu. Decreasing similarity through time among the regional floras of Antarctica, Patagonia, New Zealand, and southern Australia reflects multiple extinction events.• Gondwanan rainforest lineages contribute significantly to modern rainforest community assembly and often co-occur in widely separated assemblages far from their early fossil records. Understanding how and where lineages from ancient Gondwanan assemblages co-occur today has implications for the conservation of global rainforest vegetation, including in the Old World tropics.

Extinct conifers and conifer diversity in the Early Pleistocene of western Tasmania

Publisher: Elsevier BV

Date: 02-1995

DOI: 10.1016/0034-6667(94)00116-2

An in situ, late pleistocene Melaleuca fossil forest at Coal Head, western Tasmania, Australia

Publisher: CSIRO Publishing

Date: 2001

DOI: 10.1071/BT00049

Abstract: Stumps of more than 365 tree and shrubs are preserved in growth position on the shores of Macquarie Harbour, western Tasmania. The most likely age is Last Interglacial or early Last Glacial. The in situ forest was almost monospecific Melaleuca (probably M. ericifolia) sw forest, with one very large Nothofagus cunninghamii, occasional Acacia, interspersed with tussocks of Gahnia grandis. The Melaleuca stumps showed a more or less continuous size distribution, and tree rings suggested an age range from a few years to approximately 100 years or more. Similar vegetation occurs now in parts of lowland western and northern Tasmania, particularly in poorly drained, undisturbed, coastal sites. The composition of the in situ fossil forest differed markedly from previously recorded macrofossil and fossil palynomorph floras, suggesting that both of the latter included significant allochthonous components.

Near-tropical Early Eocene terrestrial temperatures at the Australo-Antarctic margin, western Tasmania

Publisher: Geological Society of America

Date: 03-2012

DOI: 10.1130/G32584.1

Leaf hydraulic vulnerability is related to conduit dimensions and drought resistance across a diverse range of woody angiosperms

Publisher: Wiley

Date: 25-08-2010

DOI: 10.1111/J.1469-8137.2010.03439.X

Abstract: Hydraulic dysfunction in leaves determines key aspects of whole-plant responses to water stress however, our understanding of the physiology of hydraulic dysfunction and its relationships to leaf structure and ecological strategy remains incomplete. Here, we studied a morphologically and ecologically erse s le of angiosperms to test whether the water potential inducing a 50% loss in leaf hydraulic conductance (P50(leaf)) is predicted by properties of leaf xylem relating to water tension-induced conduit collapse. We also assessed the relationships between P50(leaf) and other traits considered to reflect drought resistance and ecological strategy. Across species, P50(leaf) was strongly correlated with a theoretical predictor of vulnerability to cell collapse in minor veins (the cubed ratio of the conduit wall thickness to the conduit lumen breadth). P50(leaf) was also correlated with mesophyll traits known to be related to drought resistance, but unrelated to traits associated with carbon economy. Our data indicate a link between the structural mechanics of leaf xylem and hydraulic function under water stress. Although it is possible that collapse may contribute directly to dysfunction, this relationship may also be a secondary product of vascular economics, suggesting that leaf xylem is dimensioned to avoid wall collapse.

Conifer species adapt to low-rainfall climates by following one of two divergent pathways

Publisher: Proceedings of the National Academy of Sciences

Date: 22-09-2014

DOI: 10.1073/PNAS.1407930111

Abstract: A major determinant of plant species distribution on Earth is a specific tolerance to soil drying, yet there are currently no functional or anatomical characteristics that can predict species’ requirement for rainfall. This study examines the systems responsible for controlling water delivery and water loss in the leaves of conifers and finds functional evidence of how conifers have evolved in drying climates over the course of the last 150 million years. Two “strategies” for conserving water during water stress emerged. One group relied on the plant hormone abscisic acid to maintain stomata closed during sustained drought, and another, more derived group allowed leaves to dehydrate and resisted damage by producing a water transport system capable of functioning under the extreme tension that develops in water-stressed plants.

Evolutionary radiations of Proteaceae are triggered by the interaction between traits and climates in open habitats

Publisher: Wiley

Date: 03-06-2016

DOI: 10.1111/GEB.12481

Leaf hydraulics and drought stress: response, recovery and survivorship in four woody temperate plant species

Publisher: Wiley

Date: 08-10-2009

DOI: 10.1111/J.1365-3040.2009.02023.X

Abstract: Efficient conduction of water inside leaves is essential for leaf function, yet the hydraulic-mediated impact of drought on gas exchange remains poorly understood. Here we examine the decline and subsequent recovery of leaf water potential (Psi(leaf)), leaf hydraulic conductance (K(leaf)), and midday transpiration (E) in four temperate woody species exposed to controlled drought conditions ranging from mild to lethal. During drought the vulnerability of K(leaf) to declining Psi(leaf) varied greatly among the species s led. Following drought, plants were rewatered and the rate of E and K(leaf) recovery was found to be strongly dependent on the severity of the drought imposed. Gas exchange recovery was strongly correlated with the relatively slow recovery of K(leaf) for three of the four species, indicating conformity to a hydraulic-stomatal limitation model of plant recovery. However, there was also a shift in the sensitivity of stomata to Psi(leaf) suggesting that the plant hormone abscisic acid may be involved in limiting the rate of stomatal reopening. The level of drought tolerance varied among the four species and was correlated with leaf hydraulic vulnerability. These results suggest that species-specific variation in hydraulic properties plays a fundamental role in steering the dynamic response of plants during recovery.

Internal coordination between hydraulics and stomatal control in leaves

Publisher: Wiley

Date: 06-10-2008

DOI: 10.1111/J.1365-3040.2008.01865.X

Abstract: The stomatal response to changing leaf-atmospheric vapour pressure gradient (D(l)) is a crucial yet enigmatic process that defines the daily course of leaf gas exchange. Changes in the hydration of epidermal cells are thought to drive this response, mediated by the transpiration rate and hydraulic conductance of the leaf. Here, we examine whether species-specific variation in the sensitivity of leaves to perturbation of D(l) is related to the efficiency of water transport in the leaf (leaf hydraulic conductivity, K(leaf)). We found good correlation between maximum liquid (K(leaf)) and gas phase conductances (g(max)) in leaves, but there was no direct correlation between normalized D(l) sensitivity and K(leaf). The impact of K(leaf) on D(l) sensitivity in our erse s le of eight species was important only after accounting for the strong relationship between K(leaf) and g(max). Thus, the ratio of g(max)/K(leaf) was strongly correlated with stomatal sensitivity to D(l). This ratio is an index of the degree of hydraulic buffering of the stomata against changes in D(l), and species with high g(max) relative to K(leaf) were the most sensitive to D(l) perturbation. Despite the potentially high adaptive significance of this phenomenon, we found no significant phylogenetic or ecological trend in our species.

Mosses from early pleistocene sediments in Western Tasmania

Publisher: Informa UK Limited

Date: 1995

DOI: 10.1080/03115519508619510

A geographic mosaic of genetic variation within a foundation tree species and its community‐level consequences

Publisher: Wiley

Date: 07-2009

DOI: 10.1890/08-0951.1

Abstract: Knowledge of the manner in which genetic variation within a tree species affects associated communities and ecosystem processes across its entire range is important for understanding how geographic mosaics of genetic interactions might develop and support different communities. While numerous studies have investigated the community and ecosystem consequences of genetic variation at the hybrid cross type or genotype level within a species, none has investigated the community-level effects of intraspecific genetic variation across the geographic range of a widespread species. This is the scale at which geographic mosaics of coevolution are hypothesized to exist. Studies at this level are particularly important for foundation tree species, which typically support numerous microbial, fungal, plant, and animal communities. We studied genetic variation across eight geographical races of the forest tree Eucalyptus globulus representing its natural distribution across southeastern Australia. The study was conducted in a 15-year-old common garden trial based on families derived from single-tree open-pollinated seed collections from the wild. Neutral molecular genetic variation within E. globulus was also assessed and compared with genetic ergence in the phenotypic and community traits. Three major findings emerged. First, we found significant genetically based, hierarchical variation in associated communities corresponding to geographical races of E. globulus and families within races. Second, ergence in foliar communities at the racial level was associated with genetically based ergence in specific leaf morphological and chemical traits that have known defensive functions. Third, significant positive correlations between canopy community dissimilarity and both neutral molecular genetic and leaf quantitative genetic dissimilarity at the race level supported a genetic similarity rule. Our results argue that genetic variation within foundation tree species has the potential to be a significant driver of the geographical mosaics of variation typical of forest communities, which could have important ecological and evolutionary implications.

Living near the edge: Being close to mature forest increases the rate of succession in beetle communities

Publisher: No publisher found

Date: 2015

DOI: 10.5061/DRYAD.10C30

Seed ferns survived the end‐Cretaceous mass extinction in Tasmania

Publisher: Wiley

Date: 04-2008

DOI: 10.3732/AJB.95.4.465

Abstract: Seed ferns, dominant elements of the vegetation in many parts of the world from the Triassic to Cretaceous, were considered to have disappeared at the end of the Cretaceous together with several other groups that had occupied key positions in terrestrial and marine ecosystems such as dinosaurs, plesiosaurs, and ammonoids. Seed-fern demise is generally correlated with competition from ersifying flowering plants through the Cretaceous and the global environmental crisis related to the Chicxulub impact event in the paleotropics at the end of the period. New fossils from Tasmania show that one seed-fern lineage survived into the Cenozoic by at least 13 million years. These fossils are described here as a new species, Komlopteris cenozoicus. Komlopteris is a genus of seed ferns attributed to Corystospermaceae and until now was not known from sediments younger than the Early Cretaceous. Discovery of this "Lazarus taxon," together with the presence of a range of other relictual fossil and extant organisms in Tasmania, other southern Gondwanan provinces, and some regions of northern North America and Asia, underscores high-latitude regions as bio ersity refugia during global environmental crises and highlights their importance as sources of postextinction radiations.

NothofagussubgenusBrassospora(Nothofagaceae) leaf fossils from New Zealand: a link to Australia and New Guinea?

Publisher: Oxford University Press (OUP)

Date: 13-03-2014

DOI: 10.1111/BOJ.12143

Early evidence of xeromorphy in angiosperms: Stomatal encryption in a new eocene species of Banksia (Proteaceae) from Western Australia

Publisher: Wiley

Date: 09-2014

DOI: 10.3732/AJB.1400191

Abstract: • Globally, the origins of xeromorphic traits in modern angiosperm lineages are obscure but are thought to be linked to the early Neogene onset of seasonally arid climates. Stomatal encryption is a xeromorphic trait that is prominent in Banksia, an archetypal genus centered in one of the world's most erse ecosystems, the ancient infertile landscape of Mediterranean-climate southwestern Australia.• We describe Banksia paleocrypta, a sclerophyllous species with encrypted stomata from silcretes of the Walebing and Kojonup regions of southwestern Australia dated as Late Eocene.• Banksia paleocrypta shows evidence of foliar xeromorphy ∼20 Ma before the widely accepted timing for the onset of aridity in Australia. Species of Banksia subgenus Banksia with very similar leaves are extant in southwestern Australia. The conditions required for silcrete formation infer fluctuating water tables and climatic seasonality in southwestern Australia in the Eocene, and seasonality is supported by the paucity of angiosperm closed-forest elements among the fossil taxa preserved with B. paleocrypta. However, climates in the region during the Eocene are unlikely to have experienced seasons as hot and dry as present-day summers.• The presence of B. paleocrypta within the center of ersity of subgenus Banksia in edaphically ancient southwestern Australia is consistent with the continuous presence of this lineage in the region for ≥40 Ma, a testament to the success of increasingly xeromorphic traits in Banksia over an interval in which numerous other lineages became extinct.

Phylogeny and infrageneric classification of Correa Andrews (Rutaceae) on the basis of nuclear and chloroplast DNA

Publisher: Springer Science and Business Media LLC

Date: 07-07-2010

DOI: 10.1007/S00606-010-0315-0

Characteristics of mammal communities in Tasmanian forests: exploring the influence of forest type and disturbance history

Publisher: CSIRO Publishing

Date: 2011

DOI: 10.1071/WR10025

Abstract: Context With increasing pressure worldwide on forest habitat, it is crucial to understand faunal ecology to effectively manage and minimise impacts of anthropogenic habitat disturbance. Aims This study assessed whether differences in forest type and disturbance history were reflected in small to medium mammal communities found in Tasmania’s production forests. Methods Trapping was conducted in spring and summer, and autumn and winter during 2007–08 at four dry Eucalyptus forest sites (two regenerating after harvest and two in relatively undisturbed forest) in south-east Tasmania, and four wet Eucalyptus forest sites (two regenerating after harvest and two in relatively undisturbed forest) in north-east Tasmania. All sites were embedded within a matrix of mature or older aged regenerating forest. Key results Thirteen mammal species were recorded across all sites. There was no difference in species ersity or richness between forest type or disturbance regime, but species composition differed. Total number of in idual animals and captures was influenced strongly by forest type and disturbance history, with most animals captured in the dry disturbed forest sites. Abundance of some species (e.g. bettongs and potoroos) was higher in disturbed sites than undisturbed sites. Brushtail possum numbers (adults and offspring), however, were lower in disturbed sites and populations displayed a male biased adult sex ratio and lower breeding frequency. Habitat structural complexity and vegetation ersity within core sites, and age structure of the forest in the surrounding landscape did not vary significantly, indicating that broad resource (food and refuge) availability was equivalent across sites. Conclusions In general, the small to medium mammals in this study did not appear to be significantly affected by forest harvesting in the medium term. Implications Although past harvesting altered the abundance of some habitat features (e.g. canopy cover, basal area of trees, and tree hollow availability), we suggest that the availability of such features in the surrounding landscape may mitigate the potential effects of disturbance on the species for which such habitat features are important.

Wind affects morphology, function, and chemistry of eucalypt tree seedlings

Publisher: University of Chicago Press

Date: 2010

DOI: 10.1086/647917

Genetic differentiation in spite of high gene flow in the dominant rainforest tree of southeastern Australia, Nothofagus cunninghamii

Publisher: Springer Science and Business Media LLC

Date: 09-09-2016

DOI: 10.1038/HDY.2015.77

Cell expansion not cell differentiation predominantly co-ordinates veins and stomata within and among herbs and woody angiosperms grown under sun and shade

Publisher: Oxford University Press (OUP)

Date: 29-08-2016

DOI: 10.1093/AOB/MCW167

Data obtained from acoustic recording units and from field observer point counts of Tasmanian forest birds are similar but not the same

Publisher: BirdLife Australia, Ltd.

Date: 2018

DOI: 10.20938/AFO35030039

Early seedling establishment on aged Tasmanian tin mine tailings constrained by nutrient deficiency and soil structure, not toxicity

Publisher: CSIRO Publishing

Date: 2017

DOI: 10.1071/SR16190

Abstract: Revegetation of exposed wastes at historically abandoned mines is frequently constrained by inherent characteristics of poorly developed and contaminated soils. We tested whether the establishment of seedlings on 85-year-old arsenic rich tailings deposits at an abandoned tin mine in north-east Tasmania was limited by toxicity, nutrient limitation or structural factors. We conducted soil analyses, and tested growth of six native species in pot studies utilising both fertiliser treatments and a replacement series involving tailings and potting medium. An in situ three-year field trial was also conducted to assess the effects of adding sand, compost and biochar on plant growth and water infiltration. Analyses of the tailings identified a finely laminated structure and potential manganese, magnesium and potassium deficiencies. There was no evidence of microbial inhibition or adverse metals toxicity, pH or salinity effects. The pot trial indicated nutrient limitation acting on each of the species tested. Physical amendment within the field trial resulted in a highly significant and sustained improvement in infiltration rate, as well as improved growth in three of the six species tested. We conclude that the correction of nutritional and physical deficiencies in surface soils should overcome limitations to the early establishment of native seedlings at this site. This study shows that systematic site assessment and targeted trials is a valuable first step in the revegetation of previously recalcitrant sites.

Leaf hydraulic vulnerability influences species’ bioclimatic limits in a diverse group of woody angiosperms

Publisher: Springer Science and Business Media LLC

Date: 09-07-2011

DOI: 10.1007/S00442-011-2064-3

Abstract: The ability of plants to maintain water flow through leaves under water stress-induced tension (assessed as the leaf hydraulic vulnerability P50(leaf)) is intimately linked with survival. We examined the significance of P50(leaf) as an adaptive trait in influencing the dry-end distributional limits of cool temperate woody angiosperm species. We also examined differences in within-site variability in P50(leaf) between two high-rainfall montane rainforest sites in Tasmania and Peru, respectively. A significant relationship between P50(leaf) and the 5th percentile of mean annual rainfall across each species distribution was found in Tasmania, suggesting that P50(leaf) influences species climatic limits. Furthermore, a strong correlation between P50(leaf) and the minimum rainfall availability was found using five phylogenetically independent species pairs in wet and dry evergreen tree species, suggesting that rainfall is an important selective agent in the evolution of leaf hydraulic vulnerability. Greater within-site variability in P50(leaf) was found among dominant montane rainforest species in Tasmania than in Peru and this result is discussed within the context of differences in spatial and temporal environmental heterogeneity and parochial historical ecology.

Sensitivity of leaf size and shape to climate: global patterns and paleoclimatic applications

Publisher: Wiley

Date: 05-02-2011

DOI: 10.1111/J.1469-8137.2010.03615.X

Abstract: See also the Commentary by Burnham and Tonkovich

Impact of distance to mature forest on the recolonisation of bryophytes in a regenerating Tasmanian wet eucalypt forest

Publisher: CSIRO Publishing

Date: 2013

DOI: 10.1071/BT13250

Abstract: Forest influence is a type of edge effect that occurs when mature forests affect the recolonisation of adjacent disturbed areas. This can be driven by changes in microclimate conditions near the edge or by an increase in establishment ability with proximity to a propagule source. Bryophyte recolonisation is sensitive to both microclimate and dispersal distance, therefore they are an ideal group to examine how strong forest influence is and over what distance it operates. Responses to forest influence are known to be highly species dependent therefore, we tested whether distance affects the recolonisation ability of a range of bryophytes. As well as examining a range of species, we tested whether forest influence operated differently on two types of substrate used by bryophytes (logs and ground). For most of the species examined, establishment rates in disturbed forest diminished further away from the mature edge. The influence of unlogged mature forest on bryophyte establishment in harvested forest occurred up to 50 m. Species varied in their response to distance, and the relationships with distance were stronger on the ground compared with log substrates. These results support the concept of forest influence, with areas closer to mature forest experiencing more substantial re-establishment. These findings are relevant to conservation of bryophytes in managed native forests.

Taxodiaceous Macrofossils from Tertiary and Quaternary Sediments in Tasmania

Publisher: CSIRO Publishing

Date: 1993

DOI: 10.1071/SB9930237

Abstract: Taxodiaceous macrofossils are described from several Tertiary and Quaternary sedimentary environments in Tasmania. One new species of Athrotaxis is described, based on vegetative remains and an ovuliferous cone. This species, A. mesibovii, occurs in three sites of Oligocene–Early Miocene age and most closely resembles the extant A. selaginoides in its large leaf size. Another fossil species, Athrotaxis rhomboidea, was originally assigned to the genus Mesibovia in the Podocarpaceae, but examination of ovuliferous cones requires that it be transferred to Athrotaxis. This species was also present in several sites during the Oligocene–Early Miocene. Vegetative remains and ovuliferous cones from the Oligocene Little Rapid River site are assigned to a new species of the extinct genus Austrosequoia, which was previously only known from the Cretaceous of Queensland. The similarity of Austrosequoia to Sequoia is noted, and the possibility that the two are congeneric is emphasised.

A Toothed Lauraceae Leaf from the Early Eocene of Tasmania, Australia

Publisher: University of Chicago Press

Date: 10-2007

DOI: 10.1086/520721

The effectiveness of streamside versus upslope reserves in conserving log-associated bryophytes of native production forests

Publisher: Elsevier BV

Date: 08-2016

DOI: 10.1016/J.FORECO.2016.04.030

Links between environment and stomatal size through evolutionary time in Proteaceae

Publisher: The Royal Society

Date: 29-01-2020

DOI: 10.1098/RSPB.2019.2876

Abstract: The size of plant stomata (adjustable pores that determine the uptake of CO 2 and loss of water from leaves) is considered to be evolutionarily important. This study uses fossils from the major Southern Hemisphere family Proteaceae to test whether stomatal cell size responded to Cenozoic climate change. We measured the length and abundance of guard cells (the cells forming stomata), the area of epidermal pavement cells, stomatal index and maximum stomatal conductance from a comprehensive s le of fossil cuticles of Proteaceae, and extracted published estimates of past temperature and atmospheric CO 2 . We developed a novel test based on stochastic modelling of trait evolution to test correlations among traits. Guard cell length increased, and stomatal density decreased significantly with decreasing palaeotemperature. However, contrary to expectations, stomata tended to be smaller and more densely packed at higher atmospheric CO 2 . Thus, associations between stomatal traits and palaeoclimate over the last 70 million years in Proteaceae suggest that stomatal size is significantly affected by environmental factors other than atmospheric CO 2 . Guard cell length, pavement cell area, stomatal density and stomatal index covaried in ways consistent with coordinated development of leaf tissues.

Giant cuticular pores in Eidothea zoexylocarya (Proteaceae) leaves

Publisher: Wiley

Date: 08-2007

DOI: 10.3732/AJB.94.8.1282

Abstract: Ubiquitous, large diameter pores have not previously been adequately demonstrated to occur in leaf cuticles. Here we show conclusively that such structures occur in Eidothea zoexylocarya, a rainforest tree species of Proteaceae restricted to the Australian Wet Tropics. The pores are abundant, large-diameter apertures (∼1 μm), that extend perpendicularly most of the way through the cuticle from the inside. They occur on both sides of the leaf, but are absent from the cuticle associated with stomatal complexes on the abaxial side. No such pores were found in any other species, including the only other species of Eidothea, E. hardeniana from New South Wales, and other species that have previously been purported to possess cuticular pores. To determine whether these pores made the cuticles more leaky to water vapor, we measured astomatous cuticular conductances to water vapor for E. zoexylocarya and seven other Proteaceae species of the Wet Tropics. Cuticular conductance for E. zoexylocarya was relatively low, indicating that the prominent pores do not increase conductance. The function of the pores is currently obscure, but the presence of both pores and an adaxial hypodermis in E. zoexylocarya but not E. hardeniana suggests evolution in response to greater environmental stresses in the tropics.

Environmental niche modelling fails to predict Last Glacial Maximum refugia: niche shifts, microrefugia or incorrect palaeoclimate estimates?

Publisher: Wiley

Date: 13-09-2014

DOI: 10.1111/GEB.12239

AusTraits, a curated plant trait database for the Australian flora

Publisher: Springer Science and Business Media LLC

Date: 30-09-2021

DOI: 10.1038/S41597-021-01006-6

Abstract: We introduce the AusTraits database - a compilation of values of plant traits for taxa in the Australian flora (hereafter AusTraits). AusTraits synthesises data on 448 traits across 28,640 taxa from field c aigns, published literature, taxonomic monographs, and in idual taxon descriptions. Traits vary in scope from physiological measures of performance (e.g. photosynthetic gas exchange, water-use efficiency) to morphological attributes (e.g. leaf area, seed mass, plant height) which link to aspects of ecological variation. AusTraits contains curated and harmonised in idual- and species-level measurements coupled to, where available, contextual information on site properties and experimental conditions. This article provides information on version 3.0.2 of AusTraits which contains data for 997,808 trait-by-taxon combinations. We envision AusTraits as an ongoing collaborative initiative for easily archiving and sharing trait data, which also provides a template for other national or regional initiatives globally to fill persistent gaps in trait knowledge.

Pliocene reversal of late Neogene aridification

Publisher: Proceedings of the National Academy of Sciences

Date: 08-02-2016

DOI: 10.1073/PNAS.1520188113

Abstract: The warm climates of the Pliocene epoch are considered our best analog for a future anthropogenic greenhouse world. However, understanding of the nature of Pliocene climate variability and change on land is currently limited by the poor age control of most existing terrestrial climate archives. We present a radiometrically dated history of the evolution of Southern Hemisphere vegetation and hydroclimate from the latest Miocene to the middle Pliocene. These data reveal a sharp increase in precipitation in the Early Pliocene, which drove complete vegetation turnover. The development of warm, wet early Pliocene climates clearly reversed a long-term Southern Hemisphere trend of late Neogene cooling and aridification, highlighting the question of what initiated this sustained, ∼1.5-My-long interval of warmth.

How do soil nutrients affect within-plant patterns of herbivory in seedlings of Eucalyptus nitens?

Publisher: Springer Science and Business Media LLC

Date: 10-10-2006

DOI: 10.1007/S00442-006-0525-X

Abstract: This study assessed how the palatability of leaves of different age classes (young, intermediate and older) of Eucalyptus nitens seedlings varied with plant nutrient status, based on captive feeding trials with two mammalian herbivores, red-bellied pademelons (Thylogale billardierii), and common brushtail possums (Trichosurus vulpecula). Seedlings were grown under three nutrient treatments (low, medium and high), and we determined how palatability was related to chemical and physical characteristics of the leaves. Pademelons ate more older leaves than young and intermediate leaves for all treatments. This pattern was best explained by sideroxylonals (formylated phloroglucinol compounds known to deter herbivory by other marsupials), and/or essential oil compounds that were present in lower concentrations in older leaves. In the low-nutrient treatment, possums also ate more of the older leaves. However, in the medium- and high-nutrient treatments, possums ate more intermediate leaves than older leaves and showed a behavioural preference for young leaves (consuming younger leaves first) over intermediate and older leaves, in spite of high levels of sideroxylonals and essential oils. The young leaves did, however, have the highest nitrogen concentration of all the leaf age classes. Thus, either sideroxylonals and essential oils provided little or no deterrent to possums, or the deterrent was outweighed by other factors such as high nitrogen. This study indicates that mammalian herbivores show different levels of relative use and damage to leaf age classes at varying levels of plant nutrient status and, therefore, their impact on plant fitness may vary with environment.

Microclimatic edge effects in a recently harvested forest: Do remnant forest patches create the same impact as large forest areas?

Publisher: Elsevier BV

Date: 04-2016

DOI: 10.1016/J.FORECO.2016.01.022

The major Australian cool temperate rainforest tree Nothofagus cunninghamii withstood Pleistocene glacial aridity within multiple regions: evidence from the chloroplast

Publisher: Wiley

Date: 27-03-2009

DOI: 10.1111/J.1469-8137.2008.02761.X

Abstract: Glacial aridity of the Pleistocene was inhospitable for the cool temperate rainforest tree Nothofagus cunninghamii over most of its current range in southeastern Australia, particularly in eastern Tasmania. A chloroplast DNA phylogeographic study was undertaken to investigate whether this species was likely to have survived in situ or conforms to a dispersal model of postglacial recovery. Twenty-three chloroplast haplotypes were identified by PCR-RFLP and direct sequencing of 2164 base pairs from 213 N. cunninghamii in iduals collected in a range-wide survey. Fine-scale haplotype distribution was investigated using PCR-RFLP in eastern Tasmania. Deep chloroplast ergence occurred in N. cunninghamii. The single haplotype of the sister species, N. moorei, was nested among N. cunninghamii haplotypes. The distribution of N. cunninghamii haplotypes supports: multiple glacial refugia in coastal and inland western Tasmania, the centre of haplotype ersity glacial survival in the central highlands of Victoria, corroborating pollen data and the long-term occupation of eastern Tasmania because of the presence of a unique deeply erged chloroplast lineage. Nothofagus cunninghamii withstood glacial aridity within multiple regions in apparently nonequable climates. This finding contributes to a growing understanding of how the resilience of temperate species during glacial periods has shaped modern biota.

Fossil leaves of Banksia, Banksieae and pretenders: resolving the fossil genus Banksieaephyllum

Publisher: CSIRO Publishing

Date: 2016

DOI: 10.1071/SB16005

Abstract: The genus Banksieaephyllum, originally erected for cuticle-bearing fossil leaves of subtribe Banksiinae (Proteaceae subfamily Grevilleoideae, tribe Banksieae), is reassessed. Of the 18 described species, nine are accepted within Banksia, including Banksieaephyllum obovatum Cookson & Duigan, which is synonymised with B. laeve Cookson & Duigan on the basis of new cuticular preparations. Two other species are transferred to Banksieaefolia gen. nov., a genus erected for Banksieae of uncertain affinities, and which presently includes only fossils that probably belong to subtribe Musgraveinae. The seven other Banksieaephyllum species lack definitive characters of Proteaceae (i.e. brachyparacytic stomata and annular trichome bases) and do not have Banksieae-type cylindrical trichome bases. These species are, therefore, not accepted as Proteaceae and are transferred to Pseudobanksia gen. nov., together with another fossil Banksia-like leaf species, Phyllites yallournensis Cookson & Duigan. Lectotypes are chosen for Banksia fastigata H.Deane, Banksieaephyllum acuminatum Cookson & Duigan, Banksieaephyllum angustum Cookson & Duigan and Banksieaephyllum laeve Cookson & Duigan. Implications arising from the re-assessment of Banksieaephyllum include clarification of biome conservatism in Banksieae Banksia has long had an association with relatively open, sclerophyllous vegetation, and Musgraveinae with rainforest. Pseudobanksia and Banksia share convergent traits, but in contrast to Banksia, Pseudobanksia failed to survive the drying climates and increased fire-frequencies of the Neogene.

The dimensionality of niche space allows bounded and unbounded processes to jointly influence diversification

Publisher: Springer Science and Business Media LLC

Date: 15-10-2018

DOI: 10.1038/S41467-018-06732-X

Abstract: There are two prominent and competing hypotheses that disagree about the effect of competition on ersification processes. The first, the bounded hypothesis, suggests that species ersity is limited (bounded) by competition between species for finite ecological niche space. The second, the unbounded hypothesis, proposes that innovations associated with evolution render competition unimportant over macroevolutionary timescales. Here we use phylogenetically structured niche modelling to show that processes consistent with both of these ersification models drive species accumulation in conifers. In agreement with the bounded hypothesis, niche competition constrained ersification, and in line with the unbounded hypothesis, niche evolution and partitioning promoted ersification. We then analyse niche traits to show that these ersification enhancing and inhibiting processes can occur simultaneously on different niche dimensions. Together these results suggest a new hypothesis for lineage ersification based on the multi-dimensional nature of ecological niches that can accommodate both bounded and unbounded evolutionary processes.

The harvested side of edges: Effect of retained forests on the re-establishment of biodiversity in adjacent harvested areas

Publisher: Elsevier BV

Date: 08-2013

DOI: 10.1016/J.FORECO.2013.03.024

Water loss physiology and the evolution within the Tasmanian conifer genus Athrotaxis (Cupressaceae)

Publisher: CSIRO Publishing

Date: 2004

DOI: 10.1071/BT04029

Abstract: The Tasmanian montane and rainforest conifer genus Athrotaxis provides a system for investigating the relationship between leaf form and function and its adaptive significance. The two species differ markedly in leaf size, shape, degree of imbricacy and stomatal distribution, whereas natural hybrid swarms and glasshouse-grown hybrid progeny are highly variable for these traits. In glasshouse-grown plants of the true species and a erse hybrid progeny, stomatal conductance and density were strongly correlated, and varied by approximately 400% among in iduals. Hybrids displayed lower stomatal densities and less discrimination of 13C than the true species, leading to a negative relationship between stomatal density and δ13C. In contrast with the highly variable stomatal densities and δ13C in glasshouse plants, field-grown plants were highly conservative in both characters. This, combined with relatively low stomatal density and high water-use efficiency in field-grown plants suggests optimisation of the trade-off between assimilation and water loss. Foliar conductance in the light for the hybrids and A.selaginoides was only 4–6 times as great as, and was strongly correlated with, conductance in the dark, suggesting incomplete stomatal closure or high cuticular conductance. Athrotaxis cupressoides was less ‘leaky’. This may reflect adaptation to its more exposed habitat.

Morphometric analysis of Correa lawrenceana (Rutaceae) and the reinstatement of var. ferruginea endemic to Tasmania

Publisher: CSIRO Publishing

Date: 2013

DOI: 10.1071/SB13013

Abstract: Correa lawrenceana Hook. is a widespread species in south-eastern Australia with eight recognised varieties. The Tasmanian variety, var. lawrenceana, is morphologically erse. The present study uses multivariate morphometrics, including cluster, ordination and canonical discriminant analyses of s les of all recognised varieties of C. lawrenceana to assess whether more than one Tasmanian form warrants taxonomic recognition. These analyses showed that (1) var. lawrenceana can be ided into two well discriminated groups that are both endemic to Tasmania, a glabrescent form from the north-east and a hirsute form from the western, central and south-eastern regions, (2) the glabrescent form matches the type of C. lawrenceana and thus retains the name var. lawrenceana, and the hirsute form matches the type of C. lawrenceana var. ferruginea Hook.f. that is reinstated. The two varieties are separated geographically except in a small area around Deloraine in the north where intermediate morphological forms occur. The density of trichomes on the abaxial leaf surface is important for distinguishing the two Tasmanian varieties. An updated key to all varieties of C. lawrenceana along with descriptions of the Tasmanian varieties is presented. Nomenclature of the Tasmanian taxa is discussed and C. lawrenceana, C. lawrenceana var. glabra Benth., C. lawrenceana var. glabra L.Rodway and C. ferruginea Gunn ex Hook. are lectotypified.

Does phylogeny explain bias in quantitative DNA metabarcoding?

Publisher: Pensoft Publishers

Date: 13-06-2023

DOI: 10.3897/MBMG.7.101266

Abstract: Estimating species biomass or abundance from the number of high-throughput sequencing (HTS) reads is an aspirational goal for DNA metabarcoding, yet studies have found varied correlations. Performance varies depending on the gene marker and taxonomic group and, in part, may be related to primer-template mismatches, which are likely to exhibit phylogenetic signals. In this study, we compared commonly used fragments of two gene markers for beetles, the mitochondrial cytochrome c oxidase subunit I (COI) and 16S ribosomal RNA (16S), which have similar lengths, but different propensity for primer-template mismatches. We tested whether primer-template mismatches influence the relationship between species biomass and HTS read abundance and whether the effect of mismatches was explained by phylogeny. A significant correlation between species biomass and HTS read abundance existed for 16S, but not for COI, which had more primer-template mismatches. Models incorporating the effects of mismatch type or number improved the estimation of species biomass from HTS read abundance for COI and strong phylogenetic signals were identified. Researchers seeking to quantify biomass from metabarcoding studies should consider the effect of primer-template mismatches for the taxonomic group of interest and, for beetles, 16S appears a good candidate. Phylogenetic correction can also improve biomass estimation when using gene markers with higher primer mismatching.

Do leaves of plants on phosphorus-impoverished soils contain high concentrations of phenolic defence compounds?

Publisher: Wiley

Date: 07-01-2010

DOI: 10.1111/J.1365-2435.2009.01597.X

Past, present and future refugia for Tasmania's palaeoendemic flora

Publisher: Wiley

Date: 16-12-2016

DOI: 10.1111/JBI.12927

Fossil Ericaceae from New Zealand: Deconstructing the use of fossil evidence in historical biogeography

Publisher: Wiley

Date: 2010

DOI: 10.3732/AJB.0900109

Abstract: The Australasian Ericaceae epitomize many problems in understanding the biogeography of the southern hemisphere, especially the relative contributions of Gondwanan vicariance and dispersal. Late Cretaceous fossil pollen of the family suggests extreme antiquity of the group in Australasia, but recent phylogenetic evidence suggests much younger histories for most of the groups in that region. This paper documents two new species of latest Oligocene-Early Miocene macrofossils of Ericaceae from New Zealand. Cyathodophyllum novae-zelandiae G.J.Jord. & Bannister gen. and sp. nov. is the oldest record of the tribe Styphelieae, but is of a clade now extinct in New Zealand, possibly related to the Tasmanian genus Cyathodes. Richeaphyllum waimumuensis G.J.Jord. & Bannister sp. nov. is a member of Richeeae, but it is ambiguous as to whether it is a member of the impressive modern New Zealand radiation in Dracophyllum. These fossils emphasize the fact that at least some of the fossil pollen of Ericaceae may have been derived from extinct lineages and therefore should not be used as evidence for the antiquity of any modern New Zealand clade of Ericaceae. New fossils and/or detailed analysis of fossil and extant pollen may help resolve such uncertainty.

Glacial refugia and reticulate evolution: the case of the Tasmanian eucalypts

Publisher: The Royal Society

Date: 29-02-2004

DOI: 10.1098/RSTB.2003.1391

Abstract: Tasmania is a natural laboratory for investigating the evolutionary processes of the Quaternary. It is a large island lying 40–44° S, which was repeatedly glaciated and linked to southeastern continental Australia during the Quaternary. Climate change promoted both the isolation of species in glacial refugia, and an exchange between Tasmanian and mainland floras. Eucalyptus is a complex and erse genus, which has increased in abundance in Australia over the past 100 kyr, probably in response to higher fire frequency. Morphological evidence suggests that gene flow may have occurred between many eucalypt species after changes in their distribution during the Quaternary. This paper summarizes recent genetic evidence for migration and introgressive hybridization in Tasmanian Eucalyptus . Maternally inherited chloroplast DNA reveals a long–term persistence of eucalypts in southeastern Tasmanian refugia, coupled with introgressive hybridization involving many species. Detailed analysis of the widespread species Eucalyptus globulus suggests that migration from mainland Australia was followed by introgression involving a rare Tasmanian endemic. The data support the hypothesis that changes in distribution of interfertile species during the Quaternary have promoted reticulate evolution in Eucalyptus .

Climate drives vein anatomy in Proteaceae

Publisher: Wiley

Date: 08-2013

DOI: 10.3732/AJB.1200471

Abstract: The mechanisms by which plants tolerate water deficit are only just becoming clear. One key factor in drought tolerance is the ability to maintain the capacity to conduct water through the leaves in conditions of water stress. Recent work has shown that a simple feature of the leaf xylem cells, the cube of the thickness of cell walls ided by the lumen width (t/b)(3), is strongly correlated with this ability. Using ecologically, phylogenetically, and anatomically erse members of Proteaceae, we tested the relationships between (t/b)(3) and climate, leaf mass per unit area, leaf area, and vein density. To test relationships at high phylogenetic levels (mostly genus), we used phylogenetic and nonphylogenetic single and multiple regressions based on data from 50 species. We also used 14 within-genus species pairs to test for relationships at lower phylogenetic levels. All analyses revealed that climate, especially mean annual precipitation, was the best predictor of (t/b)(3). The variation in (t/b)(3) was driven by variation in both lumen diameter and wall thickness, implying active control of these dimensions. Total vein density was weakly related to (t/b)(3) but unrelated to either leaf area or climate. We conclude that xylem reinforcement is a fundamental adaptation for water stress tolerance and, among evergreen woody plants, drives a strong association between rainfall and xylem anatomy. The strong association between (t/b)(3) and climate cannot be explained by autocorrelation with other aspects of leaf form and anatomy that vary along precipitation gradients.

Ferns are less dependent on passive dilution by cell expansion to coordinate leaf vein and stomatal spacing than angiosperms

Publisher: Public Library of Science (PLoS)

Date: 27-09-2017

DOI: 10.1371/JOURNAL.PONE.0185648

No‐analogue associations in the fossil record of southern conifers reveal conservatism in precipitation, but not temperature axes

Publisher: Wiley

Date: 17-09-2021

DOI: 10.1111/GEB.13398

Abstract: Southern conifers have evolved under different evolutionary pressures compared with northern lineages, but in both regions these plants have undergone extensive extinction and range alteration over the Cenozoic (the last 66 Myr). It is not possible to observe the ecology of fossils directly, but indirect evidence of changes in bioclimatic envelopes can be derived from no‐analogue assemblages (i.e., groups of co‐occurring fossils that have climatically incongruous living relatives). We identify and examine the specific pairs of no‐analogue fossils within assemblages to disentangle the effects of climatic factors on past conifer extinctions and suggest which of these factors are likely to threaten southern conifer bio ersity in the future. Southern Hemisphere. Cenozoic. Conifers. We use a recently developed method, “ hyperoverlap ”, to identify no‐analogue pairs of southern conifers. We characterize each pair in terms of temperature and precipitation and evaluate temporal patterns in no‐analogue pairs. These analyses represent a novel approach to studying both no‐analogue fossils and past changes in bioclimatic envelopes. We identified 240 no‐analogue pairs in the Cenozoic record of southern conifers. Most (75.4%) observations of no‐analogue pairs are likely to result from a change in the thermal (rather than hydrological) distribution between the fossil taxa and their extant counterparts, regardless of region or assemblage age. Thus, the fossil record shows some thermal lability, but strong hydrological stability in the tolerances of these plants. This implies that most southern conifers have inhabited wet climates through the Cenozoic, which is consistent with physiological evidence suggesting strong conservatism in drought tolerance. Southern conifers have adapted successfully to a wide range of temperatures, but future changes in rainfall are likely to pose the greatest threat to these plants, either directly or indirectly (e.g., through increased incidence of fire in mesic areas).

Intraspecific variation in drought susceptibility in Eucalyptus globulus is linked to differences in leaf vulnerability

Publisher: CSIRO Publishing

Date: 2019

DOI: 10.1071/FP18077

Abstract: Understanding intraspecific variation in the vulnerability of the xylem to hydraulic failure during drought is critical in predicting the response of forest tree species to climate change. However, few studies have assessed intraspecific variation in this trait, and a likely limitation is the large number of measurements required to generate the standard ‘vulnerability curve’ used to assess hydraulic failure. Here we explore an alternative approach that requires fewer measurements, and assess within species variation in leaf xylem vulnerability in Eucalyptus globulus Labill., an ecologically and economically important species with known genetic variation in drought tolerance. Using this approach we demonstrate significant phenotypic differences and evidence of plasticity among two provenances with contrasting drought tolerance.

Gondwanan conifer clones imperilled by bushfire

Publisher: Springer Science and Business Media LLC

Date: 26-09-2016

DOI: 10.1038/SREP33930

Abstract: Global increases in fire frequency driven by anthropogenic greenhouse emissions and land use change could threaten unique and ancient species by creeping into long-term fire refugia. The perhumid and mountainous western half of Tasmania is a globally important refugium for palaeo-endemic, fire intolerant lineages, especially conifers. Reproductive strategy will be crucial to the resilience of these organisms under warmer, dryer and more fire prone climates. This study analysed clonal versus sexual reproduction in old growth plots dominated by the palaeo-endemic conifer Athrotaxis cupressoides (Cupressaceae), a species that lacks any traits to tolerate frequent landscape fire. Across most of the seven plots the amount of sexually derived in iduals was lower than clonally derived with, on average, 60% of all stems belonging to the same multi-locus lineage (MLL) (i.e. were clonal). Some MLLs were large spanning over 10 s of metres and consisted of up to 62 stems. The high mortality after fire and the rarity of sexual regeneration means that the range of this fire-intolerant species is likely to contract under enhanced fire regimes and has a limited capacity to disperse via seed to available fire refugia in the landscape.

AusTraits – a curated plant trait database for the Australian flora

Publisher: Cold Spring Harbor Laboratory

Date: 07-01-2021

DOI: 10.1101/2021.01.04.425314

Abstract: We introduce the AusTraits database - a compilation of measurements of plant traits for taxa in the Australian flora (hereafter AusTraits). AusTraits synthesises data on 375 traits across 29230 taxa from field c aigns, published literature, taxonomic monographs, and in idual taxa descriptions. Traits vary in scope from physiological measures of performance (e.g. photosynthetic gas exchange, water-use efficiency) to morphological parameters (e.g. leaf area, seed mass, plant height) which link to aspects of ecological variation. AusTraits contains curated and harmonised in idual-, species- and genus-level observations coupled to, where available, contextual information on site properties. This data descriptor provides information on version 2.1.0 of AusTraits which contains data for 937243 trait-by-taxa combinations. We envision AusTraits as an ongoing collaborative initiative for easily archiving and sharing trait data to increase our collective understanding of the Australian flora.

Similar geometric rules govern the distribution of veins and stomata in petals, sepals and leaves

Publisher: Wiley

Date: 15-05-2018

DOI: 10.1111/NPH.15210

Abstract: Investment in leaf veins (supplying xylem water) is balanced by stomatal abundance, such that sufficient water transport is provided for stomata to remain open when soil water is abundant. This coordination is mediated by a common dependence of vein and stomatal densities on cell size. Flowers may not conform to this same developmental pattern if they depend on water supplied by the phloem or have high rates of nonstomatal transpiration. We examined the relationships between veins, stomata and epidermal cells in leaves, sepals and petals of 27 angiosperms to determine whether common spacing rules applied to all tissues. Regression analysis found no evidence for different relationships within organ types. Both vein and stomatal densities were strongly associated with epidermal cell size within organs, but, for a given epidermal cell size, petals had fewer veins and stomata than sepals, which had fewer than leaves. Although our data support the concept of common scaling between veins and stomata in leaves and flowers, the large ersity in petal vein density suggests that, in some species, petal veins may be engaged in additional functions, such as the supply of water for high cuticular transpiration or for phloem delivery of water or carbohydrates.

Development of 15 nuclear EST microsatellite markers for the paleoendemic conifer Pherosphaera hookeriana (Podocarpaceae)

Publisher: Wiley

Date: 06-2018

DOI: 10.1002/APS3.1160

Two fossil species of Metrosideros (Myrtaceae) from the Oligo‐Miocene Golden Fleece locality in Tasmania, Australia

Publisher: Wiley

Date: 06-2017

DOI: 10.3732/AJB.1700095

Abstract: The capsular-fruited genus Standard paleopalynological techniques were used to date the fossil-bearing sediments. Scanning electron microscopy and an auto-montage camera system were used to take high-resolution images of fossil and extant fruits taken from herbarium specimens. Fossils are identified using a nearest-living-relative approach. The fossil-bearing sediments are palynostratigraphically dated as being These newly described fossil species of

High conifer diversity in Oligo-Miocene New Zealand

Publisher: CSIRO Publishing

Date: 2011

DOI: 10.1071/SB11004

Abstract: Eight species of Podocarpaceae foliage are recognised from the late Oligocene or early Miocene Newvale site, South Island, New Zealand, and the following five new species are described: two of Dacrydium Lamb. and one each of Dacrycarpus (Endl.) de Laub., Phyllocladus Rich. ex Mirb. and Halocarpus Quinn. The latter is the first macrofossil record of this New Zealand endemic genus. All these conifers, plus Agathis Salisb., Microcachrys Hook.f. and Podocarpus Pers., co-occurred in the local vegetation at Newvale. In conjunction with prior records of macrofossils and pollen, these fossils indicate that the late Paleogene to early Neogene conifer flora of New Zealand was very erse, with all but one of the extant genera present, together with several regionally or globally extinct genera, and multiple species of many of these genera. This fossil ersity is similar to the Paleogene fossil conifer ersity observed in south-eastern Australia (and particularly Tasmania) and in parts of North America.

An early to middle pleistocene flora of subalpine affinities in Lowland Western Tasmania

Publisher: CSIRO Publishing

Date: 1995

DOI: 10.1071/BT9950231

Abstract: Macro- and micro-fossil plants are described from Early to Middle Pleistocene sediments at Regatta Point, western Tasmania. The sediments are floristically and lithologically distinct from other sediments at the same site, and contain a precursor to modern subalpine vegetation. The sediments contain foliage, characteristic of modern western Tasmanian subalpine and alpine rainforest species. Pollen and spores suggest the presence of open vegetation similar to modem subalpine heath and herbfield. A number of taxa are inconsistent with modem high altitude vegetation, which suggests re-assortment of plant associations during periods of climate change.

Tropical palms and arums at near-polar latitudes: fossil pollen evidence from the Tamar and Macquarie grabens, northern Tasmania

Publisher: The Royal Society of Tasmania

Date: 2015

DOI: 10.26749/RSTPP.149.23

The evolutionary history of nothofagus (Nothofagaceae)

Publisher: CSIRO Publishing

Date: 1993

DOI: 10.1071/SB9930111

Abstract: A cladistic analysis of Nothofagus is presented. Comparison of potential outgroups (Fagus and Betulaceae) suggests that Fagus is most satisfactory, but clear morphological differences between it and Nothofagus support the placement of the latter in the monogeneric family Nothofagaceae. The cladistic analysis supports the four subgenera and four extant pollen groups proposed in the most recent revisions and is consistent with the extensive fossil record, although not especially supported by it. The evolution of the deciduous or evergreen habit. so long considered a singular event of importance in Nothofagus, probably occurred several times, and is an ex le of parallel evolution. Resolution within subgenera is not high in most cases, but subgenus Lophozonia offers a particularly interesting insight into the relationship among extant species and the role of rare long distance dispersal across significant ocean barriers in Nothofagus biogeography. More data are required to refine the phylogeny.

Extended differentiation of veins and stomata is essential for the expansion of large leaves in Rheum rhabarbarum

Publisher: Wiley

Date: 26-11-2023

DOI: 10.1002/AJB2.1196

Abstract: The densities of veins and stomata govern leaf water supply and gas exchange. They are coordinated to avoid overproduction of either veins or stomata. In many species, where leaf area is greater at low light, this coordination is primarily achieved through differential cell expansion, resulting in lower stomatal and vein density in larger leaves. This mechanism would, however, create highly inefficient leaves in species in which leaf area is greater at high light. Here we investigate the role of cell expansion and differentiation as regulators of vein and stomatal density in Rheum rhabarbarum, which produces large leaves under high light. Rheum rhabarbarum plants were grown under full sunlight and 7% of full sunlight. Leaf area, stomatal density, and vein density were measured from leaves harvested at different intervals. Leaves of R. rhabarbarum expanded at high light were six times larger than leaves expanded at low light, yet vein and stomatal densities were similar. In high light-expanded leaves, minor veins were continuously initiated as the leaves expanded, while an extended period of stomatal initiation, compared to leaves expanded at low light, occurred early in leaf development. We demonstrate that R. rhabarbarum adjusts the initiation of stomata and minor veins at high light, allowing for the production of larger leaves uncoupled from lower vein and stomatal densities. We also present evidence for an independent control of vein and stomatal initiation, suggesting that this adjustment must involve some unknown developmental mechanism.

Habitat type and dispersal mode underlie the capacity for plant migration across an intermittent seaway

Publisher: Oxford University Press (OUP)

Date: 27-07-2017

DOI: 10.1093/AOB/MCX086