The Heart of the Hair Fiber: How the Inner Structure of the Coat Reflects Adaptive Variation Across Color, Sex, Age, and Body Region in Dromedary Camels (Camelus Dromedarius)

The study on 138 dromedary camels examined how hair fiber structure, rather than coat color, contributes to thermoregulation in hot desert environments. It found that medullation, the inner structure of hair fibers, plays a crucial role in thermal adaptation. Dark-coated camels effectively dissipate heat despite higher surface temperatures. Factors such as sex, age, and body region also influence thermoregulatory responses, with males and adults showing higher medullation. The tail region has the highest medullation, while the belly and rump have softer hair. These findings suggest that camel hair microstructure is a multifactorial adaptive system, integrating pigmentation and inner architecture to maintain thermal homeostasis.