Human Hairs Developed to Beat Back Bugs

In an effort to discover the evolutionary advantages of human hairlessness, entomologists at UK’s University of Sheffield devised an experiment to see if parasites could have played a role. “Humans are unique among all primate species” in our superficially hairless appearance, they write. “However, despite our hairless appearance, the human body has the same density of hair follicles as would be expected of an ape of the same size.”1

While hair follicles are important for healing, sweat gland maintenance, and sensitivity to motion, evolutionists have trouble explaining why hominids lost their fur as they climbed the evolutionary ladder. Fur consists of thick terminal hair. Humans have thick terminal hair on their heads and additional discrete locations, but most of the human body is covered with fine vellus hair. Entomologists Isabelle Dean and Michael Siva-Jothy hypothesize an evolutionary advantage to the fine vellus hair. They suggest finer hair enhances “the ability to detect and remove ectoparasites [surface parasites, like bedbugs].”2

Bedbugs “cause damage and irritation through allergic reactions, blood loss and the risk of pathogenic transmission.”3 They disrupt tiny capillaries and feast on blood.

To determine the effect of body hair on bedbugs, the entomologists tested both men and women by shaving one arm and then placing a batch of hungry bedbugs on each arm. They measured the time the bugs spent finding just the right spot. Siva-Jothy says, “Just before it begins to feed, the bedbug swings its proboscis from a ‘stowed’ position to a ‘ready for action’ position.” They also measured how long it took the subjects to detect the presence of the bugs.

“All these hairs have nerves attached to them and provide us with the ability to detect displacement of the hair,” Siva-Jothy explains. “By simultaneously forming a barrier and providing detection, these hairs prolong search time and make detection more likely because the bug has to spend more time clambering over them.”

Both male and female volunteers were able to detect bedbugs more quickly on their unshaved arms.

Both male and female volunteers were able to detect bedbugs more quickly on their unshaved arms. The bedbugs took longer to pick a spot to poke on the unshaved arms of men compared to their shaved arms. However, the bugs were equally skilled on both arms of the host women. Men are generally “hairier” than women due to their higher testosterone levels.

This study did demonstrate one important function for the fine fuzz covering our bodies. But nothing in the study supported the idea that humans evolved from furry ancestors. God made apes and humans on the sixth day of Creation week, each able to reproduce after their kind. Only humans are made in the image of God. God designed humans and each kind of ape fully functional and ideally suited for the environment. This study simply reminds us that the same God who numbers the hairs on our heads (Matthew 10:30) left the fuzz on the rest of our bodies for a good reason.