While most comparative studies of between and within species phenomena focus on how species within a community may be “similar” in pattern (i.e., common vicariance), my research has sought to highlight why species may be different. I have sought to cultivate a research program focusing on the evolutionary responses of species to historical processes as a result of life history, ecological and morphological differences in a comparative context. I am primarily interested in two interconnected evolutionary research areas:
1) Reconstructing the influence of historical biogeographic processes across vertebrate communities as a means to assess how environmental, life history and phenotypic factors affect the evolutionary trajectories of species.
2) Understanding the interplay between environment, phenotype, species interactions and the demographic history of species in generating biodiversity, speciation and local adaptation.
research looks at these research foci at continent-wide, regional and landscape
scales using small vertebrate, and primarily herpetofaunal, systems to answer
consequential evolutionary questions utilizing integrative data sets and
innovative methods. However, the approaches I use may be applied to any system
of interest. I have employed an interdisciplinary approach in my research
incorporating the analysis of life history variation, morphology, species interactions, ecological
preferences, and how these factors influence species’ demographic histories and
patterns of inter- and intra-specific divergence. This has given me an interest
in how and why species are able to adapt to change, and what molecular and
functional mechanisms allow species to change. These two, interconnected questions are
particularly important in understanding historical evolution in spatially and
temporally transient environments, and are also inextricably linked to the
kinds of processes that are likely to be important determinants in if and how
organisms will cope with future climatic dynamism.
Giant Galápagos tortoise evolution
My current research in the lab of Dr. Gisella Caccone at Yale focusses on giant Galápagos tortoises. I am currently building a species tree for the radiation using massively parallel sequencing techniques I have adapted for the Ion Torrent PGM, and ddRAD sequencing. I hope to use this species tree to better resolve the evolutionary relationships among giant Galápagos tortoise species, their biogeographic history, and to reconstruct the influence of ecology on the evolution of carapace phenotypes. We are also using the ddRAD sequencing to develop a suite of SNP markers to diagnose individuals of conservation importance from Volcano Wolf (thanks to some generous funding from the Galapagos Conservancy), which involves the incorporation of NGS approaches using ancient DNA from sub-fossil remains and museum specimens collected in the early 1900's. I am also involved in the Lonesome George Genome sequencing project, and would like to explore the more functional molecular aspects of phenotypic differences in the radiation using a combination of different genomic data sets. These projects are currently underway, so come back soon for some updates!
Sunset on Dirk Hartog Island, Western Australia
Phenotype, environment, species interactions and evolution
How natural selection acts to limit species to particular environments, control species' distributions and shapes species' phenotypes are fundamental underpinnings of the study of evolution and speciation. I am interested in reconstructing the patterns of morphological evolution within and between species, and looking at how environmental conditions drive phenotypic evolution. I am also interested in the molecular mechanisms which cause phenotypic change and what might underly the ability of some species to change, where others do not. I have a couple of different projects in this area over different spatial and temporal scales and ranging from across different taxa and between species at continental scales to between populations at a landscape level. My research in this area is also leading me into thinking about how natural and sexual selection combine forces to drive adaptive diversification - this is a new and developing direction for me which I would like to continue.
Domed Giant Galápagos Tortoise - species unknown
Ecology, life history, phenotype & biogeography
I have studied biogeographic processes across many spatial scales from landscape scales to continent-wide studies, with a common theme of testing biogeographic hypotheses across taxa with disparate life history strategies, ecological preferences and physiological requirements. While, a large portion of my biogeographic research has focused on deciphering the biogeographic history of the south-western Australian biodiversity hotspot, I have also worked on species occupying the Australian wet tropics, eastern Australia, and more recently across the arid zone of Australia and the Galápagos Archipelago. I have worked on most vertebrate groups within Australia, including amphibians, reptiles and most recently dasyurid marsupials. However, the majority of my current Australian research centers on reptilian systems, as these are some of the most diverse systems within Australia in terms of in species number, phenotypic traits, ecological preferences and life history strategies. I use these systems test the role of species ecology, phenotype & life history on biogeographic responses. I am particularly interested in linking these studies with an understanding of local adaptation and its role in population divergence, especially in extreme environments.