Oladuni Tina Rissicat Lasisi

Grant Type

Dissertation Fieldwork Grant

Institutional Affiliation

Pennsylvania State U.

Grant number

Gr. 9911

Approve Date

October 25, 2019

Project Title

Lasisi, Oladuni Tina (Pennsylvania State U.) "Investigating the thermoregulatory function, genetic architecture, and evolutionary history of human scalp hair morphology"

Most hair follicles on the human body have evolved to be miniaturized, rendering us practically ‘naked’. Despite sparse body hair, we retain thick hair on our scalps that varies significantly among populations. Yet little is known of the evolutionary history of our scalp hair and its variation. It has been suggested that scalp hair, and tightly curled hair in particular, evolved to moderate thermal load in humans. However, this functional hypothesis has never been directly tested. Further, existing research on human hair variation has relied on subjective and qualitative descriptors of hair morphology and samples have been historically biased towards Eurasians. Despite its relevance to several evolutionary hypotheses, scalp hair has yet to be studied in a comprehensive evolutionary, functional, and genetic framework. This proposal seeks to 1) provide the first experimental test of the hypothesis that scalp hair (and variation in its morphology) influences thermal load, 2) investigate the genetic architecture of scalp hair morphology in a European-African admixed population with new quantitative methods, and 3) study signatures of selection at loci associated with hair.