title: Crossing the line: increasing body size in a trans-Wallacean lizard radiation (Cyrtodactylus, Gekkota).
abstract: The region between the Asian and Australian continental plates (Wallacea) demarcates the transition between two differentiated regional biotas. Despite this striking pattern, some terrestrial lineages have successfully traversed the marine barriers of Wallacea and subsequently diversified in newly colonized regions. The hypothesis that these dispersals between biogeographic realms are correlated with detectable shifts in evolutionary trajectory has however rarely been tested. Here, we analyse the evolution of body size in a widespread and exceptionally diverse group of gekkotan lizards (Cyrtodactylus), and show that a clade that has dispersed eastwards and radiated in the Australopapuan region appears to have significantly expanded its body size 'envelope' and repeatedly evolved gigantism. This pattern suggests that the biotic composition of the proto-Papuan Archipelago provided a permissive environment in which new colonists were released from evolutionary constraints operating to the west of Wallacea.
authors.affiliation: Department of Zoology, University of Melbourne, Parkville, Victoria 3052, Australia Department of Sciences, Museum Victoria, GPO Box 666, Melbourne, Victoria, Australia Research School of Biology, Australian National University, Canberra 0200, Australia paul.oliver@unimelb.edu.au.
authors.forename: Paul M
authors.initials: PM
authors.lastname: Oliver
authors.affiliation: Department of Integrative Biology and Museum of Vertebrate Zoology, University of California, Berkeley, CA 94720, USA.
authors.forename: Phillip
authors.initials: P
authors.lastname: Skipwith
authors.affiliation: South Australian Museum, North Terrace, Adelaide, South Australia 5000, Australia School of Earth and Environmental Sciences, University of Adelaide, South Australia 5005, Australia.
authors.forename: Michael S Y
authors.initials: MS
authors.lastname: Lee
mesh_terms: D000818:Animals; D001315:Australia; D005075:Biological Evolution; D049628:Body Size; D005843:Geography; D008116:Lizards / Q000145:classification*; D009512:New Guinea; D010802:Phylogeny
keywords: Asia; Cyrtodactylus; New Guinea; Wallace's Line; ecological release; insular gigantism