Kängurudjurens evolution: en integrerad paleontologisk/molekylär undersökning
Tidsperiod: 2012-01-01 till 2015-12-31
Budget: 3 200 000 SEK
The impact of large-scale environmental alteration on mammalian biodiversity is poorly understood, especially in Australasia, where many native marsupial lineages are experiencing high rates of extinction. The iconic kangaroos and rat kangaroos (Macropodiformes) have been adversely affected and yet basic knowledge of their evolutionary history is inconsistent. This project thus proposes the first multidisciplinary phylogenetic appraisal of Macropodiformes. Focus 1. Evolution Through Time. Cladistic analysis of fossils and morphological/DNA sequence data from living species will provide a coherent context for extinct/extant radiations. Conservation applications will test whether genetically divergent taxa are relict survivors of extinct lineages. Focus 2. Adaptive Trends. Optimisation of limb bone proportions, tooth forms, and body-size (reflecting digestive capability) onto phylogenetic frameworks will evaluate key adaptive developments. Chronometric scaling will permit critical evaluation of the popular but incongruous equation of hopping gaits with grassland proliferation around 10 MYA. Focus 3. Environmental Impacts. Correlative cluster analyses of macropodiform fossil occurrences with palaeobotanical and sedimentological data will compare habitat associations through time. Temporally constrained palaeoenvironmental data coded onto a phylogenetic scaffold will reconstruct radiation/extinction cycles versus the concordant history of increasing aridity over the last 20 MY.