‘Condylarths’ and the origin of odd-toed ungulate mammals

Mammals are ubiquitous in today’s world, but how did they become so successful? The textbooks say mammals bided their time for over 100 million years and then explosively diversified after dinosaurs went extinct at the end of the Cretaceous, but this has been challenged by a competing idea that mammals gradually diversified alongside dinosaurs. This debate persists because we still know very little about those mammals that flourished during the ca. 10 million years after the end-Cretaceous extinction, during the Paleocene. These so-called ‘archaic’ mammals are now represented by a wealth of new fossils, so the time is ripe to study their anatomy, phylogeny, and evolution.

This PhD project will focus on a key cluster of ‘archaic’ mammals: ‘condylarths’, a poorly understood group of primitive hoofed mammals. The particular focus of this project will be on three ‘condylarth’ subgroups: phenacodontids, hyopsodontids, and mioclaenids. Palaeontologists have long suspected some of these species to be closely related to modern perissodactyls, the hugely diverse group of odd-toed ungulates that includes horses, rhinos, and tapirs.

This PhD position is part of a new, five-year project funded by a European Research Council (ERC) Starting Grant (PalM). The ERC project will use state-of-the-art tomographic imaging to study fossils and combine evidence from anatomy and genetics to build the largest and most comprehensive phylogeny of early mammals. Then we will use this phylogeny and novel statistical methods to date the origin of modern mammal groups, determine what effect the dinosaur extinction had on mammalian biodiversity, and test for drivers of mammalian diversification.

The PhD student will work closely with the PI (Brusatte), the external co-supervisors, and other PhD students, postdocs, and external researchers in a collaborative team. The PhD project will be a stand-alone project resulting in a thesis on ‘condylarth’ evolution, but it will also contribute data to the larger team effort. The PhD project will include examination of fossil specimens in international museums (particularly the New Mexico Museum of Natural History and Science in Albuquerque and other US museums), fieldwork in the Paleocene of New Mexico, CT scanning of fossils, processing the CT scans to yield digital models, phylogenetic analysis, and statistical analysis of macroevolution. The student will be welcomed into the dynamic, and growing, vertebrate palaeontology and geobiology research group at the University of Edinburgh, along with the larger international research consortium funded by the ERC. He/she will gain training in: vertebrate anatomy, phylogenetic methods and systematics, CT imaging (segmenting and rendering), scientific illustration, conference presentations, scientific publishing, networking skills, and public engagement with research (a key strength of the Edinburgh group and PI Brusatte). The PhD student will publish their work as part of several planned high-impact papers.