A multi-disciplinary approach to the analysis of crocodylian phylogeny, diversity and biogeographic history in Deep Time

Past Life and Environments

UCL

UCL

Paul Barrett (Natural History Museum),

Crocodylians are one of the oldest extant lineages on the planet, having originated towards the late Triassic over 200 Ma. Their large fossil diversity stands in contrast to only 23 living species and as such provides a rich source for studies of phylogeny, biogeography and disparity changes throughout time. This project will examine the evolution of a group of both extant and fossil crocodiles, the Neosuchia, since their emergence in the Cretaceous (145 Ma) using both morphological and molecular data for a comprehensive new phylogeny. Enhanced methods in morphometrics such as CT-scanning will improve our knowledge of disparity throughout time and allow conclusions about the palaeoecology of Neosuchia. As such the analysis will facilitate the evaluation of responses of the lineage to changing climate in the past and present. The new data gathered will also help and clarify the issue of homoplastic characters and their influences on the tree and help resolve the current disagreements between morphological and molecular data sets, as well as shine light on biogeographical questions concerning the distribution patterns of both extant and fossil crocodylian taxa.

• Bogue Fellowship – UCL

• Groh S, Upchurch P, Barrett, Day JJ (2020) The phylogenetic relationships of neosuchian crocodiles and their implications for the convergent evolution of the longirostrine condition. Zoological Journal of the Linnean Society DOI: https://doi.org/188(2): 473-506. 10.1093/zoolinnean/zlz117doi.org/10.1093/zoolinnean/zlz117
• Groh S, Upchurch P, Barrett, Day JJ (2022) How to date a crocodile: estimation of neosuchian clade ages and a comparison of four time-scaling methods Palaeontology DOI: https://doi.org/10.1111/pala.12589