Funding Source: CENTA DTP
Proposed start date: 27th September 2021
Project Highlights:
• Use new techniques to shed fresh light on a long-standing evolutionary question – the diversity of mammals after the extinction of dinosaurs
• Acquire a suite of skills for quantitative statistical analysis of textures, morphology and evolutionary patterns
• Opportunities to travel to collect data from fossil collections across Europe and the US, and conduct fieldwork in New Mexico
Overview:
This project will use new techniques to address one of the perennial questions in palaeontology: the impact of dinosaurs and their extinction on mammal evolutionary history. A number of recent studies have focussed on the timing of mammal diversification (e.g. Wilson et al. 2012, Close et al. 2015, Grossnickle 2019), but it is more difficult to test hypotheses of ecological diversity. Morphological analysis of well-preserved articulated mammal skeletons of Jurassic age is starting to paint a picture of mammals occupying a broader range of ecological niches than previously thought, but the majority of fossil mammals are known only from disarticulated remains and teeth, and are not amenable to this type of functional analysis. Consequently, the degree to which their ecological diversity was affected by the K-Pg extinction, and the pattern of ecological diversification during the Palaeocene, have been difficult issues to address.
This project will employ a new approach rarely applied to mammals of this age: dental microwear texture analysis (DMTA). The application of this approach to early mammals was pioneered by the supervisors (Purnell et al. 2013, Gill et al. 2014). You will combine this with other dietary proxies (isotopic data, mesowear and quantitative shape analysis of teeth) in phylogenetic context, to conduct multidisciplinary, multiproxy investigation of the dietary diversity of Palaeocene mammals, and of the patterns of trophic niche occupation and partitioning. You will establish the dietary guilds to which the early members of modern mammal lineages belong. DMTA has revealed hidden trophic diversity in Jurassic mammals, indicating that lineage splitting during the earliest stages of mammalian evolution was associated with ecomorphological specialization and niche partitioning (Gill et al. 2014). This project, applying the approach to Palaeocene fossils, will similarly yield new insights into the evolutionary history of mammals.
This project is ideal for applicants with a first degree in geological or biological sciences and an aptitude for quantitative analysis. At the University of Leicester you will join a dynamic group of researchers, PhD and Masters students working on novel analyses of diet and trophic niche in fossil vertebrates.
Methodology:
The project will focus on material from the San Juan Basin of New Mexico – one of the world’s premier localities for Palaeocene mammal fossils. The collections, held in the New Mexico Museum of Natural History, include new material recently excavated by the supervisors, and the project offers opportunities for fieldwork in New Mexico. Dietary analysis will employ quantitative 3D Microwear texture analysis using multivariate methods developed at the University of Leicester (Purnell et al. 2013, Gill et al. 2014). Combining this with mesowear analysis, isotopic data, functional morphological analysis, and quantitative phylogenetic methods will allow robust analysis and hypothesis testing of the role of feeding and diet at different temporal and spatial scales. This approach will allow independent testing of dietary hypotheses, and evaluation of specific roles within broader dietary guilds, and has the potential to pick up dietary transitions that predate and potentially drive morphological adaptation of teeth to new functional roles.
Training and skills:
Students will be awarded CENTA2 Training Credits (CTCs) for participation in CENTA2-provided and ‘free choice’ external training. One CTC equates to 1⁄2 day session and students must accrue 100 CTCs across the three years of their PhD.
Specialist training will include tooth microwear analysis, techniques for phylogenetic testing and analysis of macroevolutionary patterns, and tooth shape analysis. The emphasis will be on robust quantitative analysis and statistical hypothesis testing.
Entry requirements:
Applicants are required to hold/or expect to obtain a UK Bachelor Degree 2:1 or better in a relevant subject.
The University of Leicester English language requirements apply where applicable: https://le.ac.uk/study/research-degrees/entry-reqs/eng-lang-reqs
Application advice:
To apply please refer to https://le.ac.uk/study/research-degrees/funded-opportunities/centa-phd-studentships
Project / Funding Enquiries: Mark Purnell [Email Address Removed] or [Email Address Removed]
Application enquiries to [Email Address Removed]