Doctoral Dissertation Research: Unraveling the evolutionary mechanisms associated with miniaturization

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2).

Extreme reductions in body size evolved multiple times within the primate tree-of-life, a process thought to provide evidence of convergent evolution. This doctoral dissertation research project compares whole-genomes of various species to examine the evolutionary processes and biological mechanisms explaining body size reduction in primates. The project leverages historical museum collections to generate novel whole genomes of primate species that fill important gaps in genomic databases.

All data generated in this study will be made publicly available to provide additional research opportunities beyond the scope of this project. Outcomes of this research contribute to the understanding of primate genetic architecture, thus allowing a better contextualization of human genomic variation in an evolutionary framework. Moreover, this project extends bioinformatics training opportunities and accessibility of students from historically underrepresented groups.

Convergent evolution provides compelling evidence that similar ecological circumstances can lead to similar evolutionary solutions. However, the role of natural selection in primate size reduction remains largely speculative, especially when it comes to understanding how adaptation occurs at the molecular level. It is not clear if all small-sized primates evolved such diminutive body size via changes in the same genetic mechanisms, or if changes in different combinations of genes and regulatory sequences could lead to similar outcomes.

To address these standing questions, the investigators will compare whole-genome sequences of pairs of miniaturized and non-miniaturized species to access the degree of similarity at the molecular level and the pace of molecular evolution. This research specifically examines: (1) whether small-sized species share the same genetic underpinnings; (2) evidence of selection acting in protein-coding regions related to size reduction in primates.

Results will inform a more general understanding of how bodily variation arises over evolutionary history.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.