Researchers at Pennsylvania State University conducted a study suggesting that the presence of curly hair in humans may be linked to thermoregulation challenges. The findings appear in the bioRxiv preprint catalog, indicating preliminary results that await peer review before final publication.
Humans are unique among primates in lacking body fur, yet the scalp is typically covered with hair, and in some people the hair forms curls. No other animal species has truly curly hair. For years scientists have hypothesized that this curl pattern could influence sweating and heat management when people are exposed to high temperatures.
In a novel experimental setup, researchers examined different hair appearances by testing wigs on a mannequin. The lineup included straight, wavy, and curly wigs. The data showed that any hair at the scalp reduces heat absorption to some extent, but curly hair demonstrated a notably greater impact on cooling the scalp.
The process of sweating consumes energy because it requires the production and maintenance of moisture. The study’s outcomes imply that scalp hair may serve as a natural cooling mechanism for the brain, particularly in hot and dry climates where access to water is limited.
These results are currently considered preliminary and will require validation through peer-reviewed publication to establish broader scientific consensus.