Quantifying species diversity with accuracy has important implications that extend from the life sciences and into science policy, habitat management, and conservation. However, since speciation is expected to proceed independently across each branch of the tree of life, identifying a fixed threshold that demarcates the boundary between populations and species has remained elusive. The lack of a unified framework for deciding whether populations should be elevated to species has produced a heterogeneous inventory of species diversity. In this talk, I will present a synthesis of traditional and modern species concepts and present a new genomic method that considers speciation as a continuum where the population–species boundary exists along a spectrum from interbreeding populations to completely isolated species. I will present analyses using the diverse lizard fauna of North America to illustrate this comparative approach to species delimitation, which combines recent conceptual, methodological, and empirical advances.
Adam Leaché is currently visiting the Biodiversity Computing Group of ICS-FORTH and will be in Crete until the end of May. Adam Leaché is a Professor of Biology at the University of Washington and Curator of Herpetology and Genetic Resources at the Burke Museum of Natural History and Culture. He received his Ph.D. from the University of California, Berkeley in the field of Integrative Biology where he conducted biodiversity research in the Museum of Vertebrate Zoology. He is a Fulbright Scholar and a McNair Scholar, and the recipient of the Distinguished Teaching Award from the University of Washington and the Ernst Mayr Award from the Society of Systematic Biologists.