Doctoral Dissertation Research: Social relationships, predation risks, and primate sleep

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

This doctoral dissertation research investigates how group-living primates decide where to sleep at night, and how their choice of where to sleep influences their sleep quality. The project considers how physical features of the environment as well as the differentiated and multi-faceted social relationships that are characteristic of primate group mates impact this important decision.

By investigating the consequences of this choice on sleep quality, the research provides a comparative perspective for understanding how early human ancestors survived night predation and obtained sufficient sleep while doing so. This project supports STEM research capacity building at the field site as well as interdisciplinary research opportunities to both undergraduate and graduate students from groups underrepresented in STEM.

There are plans to share products of this research with academic and public audiences through scientific manuscripts, public lectures, and popular-science blog contributions.

Like other savannah-dwelling primates, baboons seek refuge at night in trees and on cliffs to mitigate the risk of nocturnal predation. When choosing a spot in which to sleep within the nighttime refuge, baboons face not only a heterogeneous physical environment that could create asymmetries in the perceived quality of sleep spot alternatives, but also a variable ecological context and dynamic social environment that could further modulate the preferences and availability associated with each sleep spot.

Despite substantial research interest, practical limitations have prevented a systematic investigation of how primates navigate this critically important, yet complex decision-making landscape. This project combines traditional field methods in primatology with the latest technological advances to overcome practical limitations, allowing investigators to (1) characterize baboons’ sleep spot preferences; (2) assess how individuals update their sleep spot choices in a dynamic social environment; (3) determine whether acquiring a preferred sleep spot translates to a measurable benefit for sleep; and (4) test how the perceived risk of predation affects sleep spot decision-making dynamics and sleep quality.

The project uses methods in field primatology to describe the group's social dynamics, 3D laser scanning to assess metrics of sleep spots, thermal imagery and convolutional neural networks to track baboons' decisions throughout the night, accelerometry to evaluate sleep quality, and predator playbacks to manipulate the perceived risk of predation. By examining these aims using olive baboons, the collaborative and interdisciplinary research informs discussions of how early human ancestors may have made complex decisions when they were most vulnerable.

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.