Dan Rabosky



Research Overview

I study evolutionary diversification in the broad sense. My interests range from the role of ecological interactions in the speciation process to factors that determine the fates of clades over epochal timescales. I'm especially interested in understanding why evolutionary radiations so often show radically different outcomes. Why do some groups of organisms have so many species, and why do so many other groups have so few species? Likewise, why do some groups show so much more ecological and phenotypic diversity relative to other groups? These patterns are ubiquitous across the spectrum of biological diversity, yet their causal basis remains poorly understood.

My work in this area involves both comparative analyses of diversification as well as the development of analytical tools for hypothesis testing. A sampling of questions I'm working on at the moment: what factors influence rates of speciation and extinction during radiations, and how can we study them with molecular phylogenies? Do speciation rates during evolutionary radiations show diversity dependence? How can we combine inferences from molecular phylogenies and the fossil record to understand the dynamics of speciation and extinction through time? Do rates of phenotypic evolution vary during evolutionary radiations, and how can we infer these rates?

I also study ecological and lineage diversification in the Australian skink (= lizard) genus Ctenotus. With approximately 100 described species, Ctenotus is one of the most diverse genera of terrestrial vertebrates. We have shown that Ctenotus is characterized by exceptionally high rates of diversification relative to other lineages of Australian skinks. Many fascinating questions remain. Why have these groups experienced such explosive diversification? What are the relative roles of geographic isolation and ecological interactions in Ctenotus speciation? What are the links between the aridification of Australia and diversification in Ctenotus and other groups of Australian vertebrates?

Selected Publications

Rabosky, D. L. 2009. Ecological limits and diversification rate: alternative paradigms to explain the variation in species richness among clades and regions. Ecology Letters 12: 735-743.

Rabosky, D. L. 2009. Heritability of extinction rates links diversification patterns in molecular phylogenies and the fossil record. Systematic Biology, in press.

Rabosky, D. L., and A. R. McCune. 2009. Reinventing species selection with molecular phylogenies. Trends in Ecology and Evolution. Doi:10.1016/j.tree.2009.07.002.

Rabosky, D. L., and U. Sorhannus. 2009. Diversity dynamics of marine planktonic diatoms across the Cenozoic. Nature 457:183-186.

Rabosky, D. L. 2009. Ecological limits on clade diversification in higher taxa. American Naturalist 173:662-674.

Rabosky, D. L., A. L. Talaba, S. C. Donnellan, and I. J. Lovette. 2009. Molecular evidence for hybridization between two Australian desert skinks, Ctenotus leonhardii and Ctenotus quattuordecimlineatus (Scincidae : Squamata). Molecular Phylogenetics and Evolution 53:368-377.

Rabosky, D. L. and I. J. Lovette. 2009. Problems detecting density-dependent diversification on phylogenies: reply to Bokma. Proceedings of the Royal Society of London, Series B 276:995-997.

Rabosky, D. L., and I. J. Lovette. 2008. Density dependent diversification in North American wood-warblers. Proceedings of the Royal Society of London, Series B 275: 2363-2371.

Rabosky, D. L., and I. J. Lovette. 2008. Explosive evolutionary radiations: decreasing speciation or increasing extinction through time? Evolution 62:1866-1875.

Rabosky, D. L., S. C. Donnellan, A. L. Talaba, and I. J. Lovette. 2007. Exceptional among-lineage variation in diversification rates during the radiation of Australia's largest vertebrate clade. Proceedings of the Royal Society of London, Series B 274:2915-2923.

Rabosky, D. L, J. Reid, M. A. Cowan, and J. Foulkes. 2007. Community-wide overdispersion of body size in Australian desert lizard communities. Oecologia 154:561-570.

Rabosky, D. L. 2006. LASER: a maximum likelihood toolkit for detecting temporal shifts in diversification rates from molecular phylogenies. Evolutionary Bioinformatics Online 2:257-260.

Rabosky, D. L. 2006. Likelihood methods for inferring temporal shifts in diversification rates. Evolution 60:1152-1164.

Rabosky, D. L, K. P. Aplin, S. C. Donnellan, and S. B. Hedges. 2004. Molecular phylogeny of blindsnakes (Ramphotyphlops) from Western Australia and resurrection of Ramphotyphlops bicolor (Peters, 1857). Australian Journal of Zoology 52:531-548.