Latitudinal gradients in biotic processes affecting plant growth and establishment. The idea that plant-animal interactions are more intense in the tropics underpins much thinking about tropical ecology, global patterns in plant traits, and latitudinal gradients in biodiversity. In this project, we will provide the first direct and global test of this idea by quantifying the intensity of herbivory, seed predation and density-dependent seedling mortality at approximately 100 study sites around th ....Latitudinal gradients in biotic processes affecting plant growth and establishment. The idea that plant-animal interactions are more intense in the tropics underpins much thinking about tropical ecology, global patterns in plant traits, and latitudinal gradients in biodiversity. In this project, we will provide the first direct and global test of this idea by quantifying the intensity of herbivory, seed predation and density-dependent seedling mortality at approximately 100 study sites around the world. We will also investigate the causes of these latitudinal gradients by determining which environmental variables are most closely associated with the strength of biotic interactions.Read moreRead less
Were the Tertiary radiations of the Australian flora synchronous? A molecular phylogenetic approach. The fossil record shows that in a short period from about 20 Mya, the ancestral Gondwanan rainforest gave way to the unique Australian ?sclerophyll? flora dominated by eucalypts, acacias and casuarinas. This coincided with a drying climate and the advent of fire. It is hypothesized that ?explosive? evolutionary radiations rapidly increased the number of sclerophyll species, rather than a mere r ....Were the Tertiary radiations of the Australian flora synchronous? A molecular phylogenetic approach. The fossil record shows that in a short period from about 20 Mya, the ancestral Gondwanan rainforest gave way to the unique Australian ?sclerophyll? flora dominated by eucalypts, acacias and casuarinas. This coincided with a drying climate and the advent of fire. It is hypothesized that ?explosive? evolutionary radiations rapidly increased the number of sclerophyll species, rather than a mere range expansion of pre-existing species. In a novel approach, molecular phylogenies of several distantly related plant groups will be used to test whether explosive evolutionary radiations took place simultaneously and to identify the environmental triggers.Read moreRead less
A framework linking tree species coexistence, zonation and patterns of species richness in forests. Our curiosity-driven proposal capitalizes on a superb opportunity afforded by the occurrence of forest vegetation across a wide range of climates and soils in eastern Australia, an ideal setting for testing ideas about how environment shapes plant evolution as well as forest structure and dynamics. This research will contribute to international interchange of ideas by promoting interaction with co ....A framework linking tree species coexistence, zonation and patterns of species richness in forests. Our curiosity-driven proposal capitalizes on a superb opportunity afforded by the occurrence of forest vegetation across a wide range of climates and soils in eastern Australia, an ideal setting for testing ideas about how environment shapes plant evolution as well as forest structure and dynamics. This research will contribute to international interchange of ideas by promoting interaction with collaborators in New Zealand, and will generate a series of publications in high-impact international journals. We will help Australians better understand the forces that shape patterns of woody vegetation across local landscapes, and our carbon-balance framework may shed light on the causes of rarity of some tree species with conservation problems.Read moreRead less
Effects of ants and ant-mediated dispersal on speciation rates, biogeography and diversity of angiosperms. This work seeks to improve our general understanding of longstanding questions in ecology in evolution, namely what are the processes that have allowed some groups to become diverse and others not, why does dispersal mode vary with geography, and how do speciation and extinction vary across space, time and taxon? In answering these questions, we will address some of the most fundamental que ....Effects of ants and ant-mediated dispersal on speciation rates, biogeography and diversity of angiosperms. This work seeks to improve our general understanding of longstanding questions in ecology in evolution, namely what are the processes that have allowed some groups to become diverse and others not, why does dispersal mode vary with geography, and how do speciation and extinction vary across space, time and taxon? In answering these questions, we will address some of the most fundamental questions in conservation, including what are the factors that make species geographically rare, which species are most at risk for climate change, and what are the factors that have led habitats like the Kwongan Heath and Fynbos to be so exceptionally biodiverse.Read moreRead less