This article has been peer reviewed and accepted for publication. It is in production and has not been edited, so may differ from the final published form.
A novel approach to time-slicing areas within biogeographic area classifications: Wallacea as an example
Time-slicing of areas is a novel biogeographic method that helps to resolve conflicting area relationships and assess temporal overlap as an explanation for the conflict. The method differs from others currently popular in biogeography in that is does not date nodes prior to analysis (i.e., is does not model) to infer area relationships and classification. Here, time-slicing is used as a proof of concept approach to interpret the interrelationships of Neogene and Palaeogene biotic areas of Wallacea, a well-studied area of biogeographic overlap between Southeast Asia and Australasia. We used 18 Palaeogene and 25 Neogene areas within Wallacea represented in 28 areagrams from 25 published phylogenetic hypotheses. Areas were delimited using palaeogeographical reconstructions and biotic distribution data. The paralogy-free subtree and transparent methods were used to find a general area cladogram (GA), which was then compared to palaeogeographical reconstructions. Palaeogene areas formed clades different to those of Neogene areas. Area relationships correlated strongly with palaeogeographical reconstructions of the Neogene and the Palaeogene. The new approach demonstrates that Palaeogene and Neogene areas have distinct biogeographic histories. Wallacea is a temporal as well as a geographic composite that lies between two inferred barriers to distribution: the Palaeogene Wallace’s Line and the Neogene Weber’s Line
SB17028 Accepted 25 August 2017
© CSIRO 2017