Completeness of the dinosaur fossil record: disentangling geological and anthropogenic bias

[摘要] Non-avian dinosaurs were a highly successful clade of terrestrial tetrapods that dominated Mesozoic ecosystems. Their public and scientific popularity makes them one of most intensely researched and understood fossil groups. Key to our understanding of their evolutionary history are interpretations of their changing diversity through geological time. However, spatiotemporal changes in fossil specimen completeness, diagnostic quality, and sampling availability can bias our understanding of a group’s fossil record. Methods quantifying the level of skeletal and phylogenetic information available for a fossil group have previously been used to assess potential bias. In this thesis, these methods are used to critically assess the saurischian dinosaur fossil record, including an examination of changes in specimen completeness through research time. Novel metrics are presented that quantify the diagnostic quality of fossil specimens and assemblages. Results suggest that recent changes in our understanding of the dinosaur fossil record mostly derive from taxonomic and stratigraphic revisions. The completeness of the sauropodomorph fossil record is temporally segregated, whereas the theropod record is heavily spatially and environmentally biased, plus shows signs of taphonomic and taxonomic identification bias towards particular subgroups. These results represent a significant contribution to better understanding the nature of the dinosaur fossil record.

[发布机构] University:University of Birmingham;Department:School of Geography, Earth and Environmental Sciences

[关键词] Q Science;QE Geology