Female multiple mating and the evolutionary origins of complex societies. This project plans to connect micro-evolutionary processes with macro-evolutionary change to provide a unified understanding of why animals live together. Evolutionary transitions to and from complex social behaviour appear linked to female multiple mating (polyandry). However, the causal pathway by which variation in polyandry results in the emergence and diversification of sociality is yet to be established. Using a vert ....Female multiple mating and the evolutionary origins of complex societies. This project plans to connect micro-evolutionary processes with macro-evolutionary change to provide a unified understanding of why animals live together. Evolutionary transitions to and from complex social behaviour appear linked to female multiple mating (polyandry). However, the causal pathway by which variation in polyandry results in the emergence and diversification of sociality is yet to be established. Using a vertebrate system we aim to integrate empirical, theoretical and comparative approaches to show: the ecological causes of individual variation in female polyandry; its effect on social behaviours that promote social complexity at the population level; and how this corresponds to divergence in social complexity across species.Read moreRead less
Does mother know best? Unifying proximate causation and ultimate explanation in mammalian sex allocation. The study of parental effects is a fundamental area in evolutionary ecology, but is characterised by poor integration of theory (ultimate causation) and physiology (proximate causation). This is true in sex allocation research that focuses almost exclusively on ultimate causation without integrating the physiological mechanisms for sex ratio adjustment. Using a combination of experiments and ....Does mother know best? Unifying proximate causation and ultimate explanation in mammalian sex allocation. The study of parental effects is a fundamental area in evolutionary ecology, but is characterised by poor integration of theory (ultimate causation) and physiology (proximate causation). This is true in sex allocation research that focuses almost exclusively on ultimate causation without integrating the physiological mechanisms for sex ratio adjustment. Using a combination of experiments and modelling, the project addresses this gap in understanding mammalian sex allocation, specifically: the lack of known mechanism; the connection between proximate mechanistic explanation and adaptive fitness explanations; and, knowledge on constraints. This project argues that one mechanism, pre-implantation glucose levels, links adaptive hypotheses with proximate causation. Read moreRead less
Transformation of vegetation by big herbivores, from the Pleistocene to now. The project aims to provide a coherent understanding of the effects of extinct and extant large herbivores on ecosystems over space and time. The structure and distribution of vegetation types is determined not only by climate and soils, but also by the impacts of herbivores and fire as consumers of plant biomass. Recent research has shown how fire shapes the large-scale distribution of vegetation types, but we do not h ....Transformation of vegetation by big herbivores, from the Pleistocene to now. The project aims to provide a coherent understanding of the effects of extinct and extant large herbivores on ecosystems over space and time. The structure and distribution of vegetation types is determined not only by climate and soils, but also by the impacts of herbivores and fire as consumers of plant biomass. Recent research has shown how fire shapes the large-scale distribution of vegetation types, but we do not have an equivalent understanding of the effects of large ground-dwelling herbivores. The project plans to test the effects of such animals on vegetation structure in the Pleistocene, when mega-herbivores were common, and today, and thus to compare the impacts of fire and herbivores on the distribution of vegetation types.Read moreRead less
Species redundancy in response to multiple disturbances. This project aims to elucidate how the context within which disturbances occur affects food web linkages and how these map to responses in ecosystem function. There is a critical need to test the common assumption in environmental management that high biodiversity makes ecosystems resilient to disturbances. Studies that merely observe biodiversity change after disturbance cannot identify ecological processes connecting high diversity and e ....Species redundancy in response to multiple disturbances. This project aims to elucidate how the context within which disturbances occur affects food web linkages and how these map to responses in ecosystem function. There is a critical need to test the common assumption in environmental management that high biodiversity makes ecosystems resilient to disturbances. Studies that merely observe biodiversity change after disturbance cannot identify ecological processes connecting high diversity and ecosystem function, making experiments that manipulate identical disturbances in ecosystems with different biodiversity essential. This project will use field experiments that manipulate disturbances in streams replicated in low and high biodiversity regions and across gradients of chronic background stress to show how biodiversity sustains functional ecosystems, and how much diversity can be lost before ecosystems collapse.Read moreRead less
The failure-threshold of leaves in drought. This project aims to reveal how specific water-stress thresholds damage the leaves of Australian crop and forest species during drought. Water stress affects agricultural productivity and plant survival in drought-prone regions such as Australia. Using optical and X-ray techniques, this project seeks to visualise and quantify the dynamic processes of damage and repair in leaves under stress. Anticipated outputs include a practical basis to predict drou ....The failure-threshold of leaves in drought. This project aims to reveal how specific water-stress thresholds damage the leaves of Australian crop and forest species during drought. Water stress affects agricultural productivity and plant survival in drought-prone regions such as Australia. Using optical and X-ray techniques, this project seeks to visualise and quantify the dynamic processes of damage and repair in leaves under stress. Anticipated outputs include a practical basis to predict drought-induced canopy death; identification of threats to ecologically sensitive plants; and selection and screening tools to improve the drought resilience of agriculturally important crop species.Read moreRead less
Using animal-borne cameras to quantify prey field, habitat characteristics and foraging success in a marine top predator. To understand the factors which influence population dynamics, knowledge of habitat use is required. This project will determine the key ecological characteristics of the Australian fur seal habitat, enabling fundamental issues of foraging ecology and wildlife management to be addressed for the first time in a marine mammal.
Reconstructing past population dynamics to understand human and climatic impacts in prehistory. More than 100 species have become extinct since humans first colonised Australia, and over 1000 are considered threatened. This research will determine the factors most strongly governing the interaction between humans and native fauna in Australia over the last 46 millennia. Our approach is powerful and novel because it will effectively draw together multidisciplinary evidence on natural resource exp ....Reconstructing past population dynamics to understand human and climatic impacts in prehistory. More than 100 species have become extinct since humans first colonised Australia, and over 1000 are considered threatened. This research will determine the factors most strongly governing the interaction between humans and native fauna in Australia over the last 46 millennia. Our approach is powerful and novel because it will effectively draw together multidisciplinary evidence on natural resource exploitation and habitat alteration by ancient people, and the influence of dramatic climatic shifts on the Australian biota. Information on past biological responses to environmental change is critical to properly contextualising the current impact, and long-term consequences of, threats such as global warming, habitat loss and invasive species.Read moreRead less
Plasticity and the origins of family. This project aims to answer the question of how family life evolved. Humans and many animals live in stable family groups because of the benefits of cooperation. Surprisingly, we have a very poor understanding of how family living initially evolved. This project will experimentally determine how simple responses to environmental change have driven the evolution of family living and thereby refine theories for understanding social evolution more generally. ....Plasticity and the origins of family. This project aims to answer the question of how family life evolved. Humans and many animals live in stable family groups because of the benefits of cooperation. Surprisingly, we have a very poor understanding of how family living initially evolved. This project will experimentally determine how simple responses to environmental change have driven the evolution of family living and thereby refine theories for understanding social evolution more generally. This information will be useful to environmental policy makers that need to consider the role of environmental change in managing and conserving viable populations.Read moreRead less
How has bushfire activity varied around the Southern Hemisphere over the last 10,000 years? We will determine the relative contribution of climate and human ignitions in driving bushfire activity around the Southern Hemisphere over the last 10,000 years. Such knowledge is crucial for ecologically sustainable fire management, resolving debates about past Aboriginal environmental impacts and understanding the risk posed by climate change.
Effects of maternal foraging success and oceanographic variation on offspring behaviour and survival in the southern elephant seal. Juvenile survival is the key determinant of mammalian population performance, but the proximate determinants of this have rarely been established in large, long-lived predators. Southern elephant seals, with their concentrated lactation effort and marked separation of energy acquisition (at-sea foraging) and expenditure (on-land lactation) provide an ideal model for ....Effects of maternal foraging success and oceanographic variation on offspring behaviour and survival in the southern elephant seal. Juvenile survival is the key determinant of mammalian population performance, but the proximate determinants of this have rarely been established in large, long-lived predators. Southern elephant seals, with their concentrated lactation effort and marked separation of energy acquisition (at-sea foraging) and expenditure (on-land lactation) provide an ideal model for investigating these factors. In this study, we investigate the partitioning of pre-partum performance (fat acquired in mothers) relative to spatial-temporal variation in ocean productivity and the effect of this expenditure on offspring condition and survival. Here, the final missing link of energy transfer and its effects on offspring will be a major outcome of this project.Read moreRead less