Hairy Skin May Keep the Bedbugs From Biting

 

Photo by Darlyne A. Murawski

 

According to new research, having hairy skin may help a person ward off bedbugs.  Participants in a study conducted by scientists at the University of Sheffield released the nighttime bloodsuckers on themselves and observed the bugs’ feeding habits.  Bedbugs placed on shaved arms were more likely to try to feed than those that were placed on unshaven limbs.

Why?  Hair makes it more difficult for bedbugs to find a place to feed, and the nerve endings in follicles help alert us to the presence of intruders.  But thick hair can also make it easier for parasites to hide and harder for hosts to find them. This game of hide-and-seek may be the reason why modern humans have only a fine layer of hair (called vellus) in place of the furry coats that our ancestors sported:  eventually the reduction of parasite-borne diseases outweighed the protective benefits of having more hair.

The full results of the study can be found in the journal Biology Letters.

For all the latest science news, check out the National Geographic’s twice-weekly news rundown, EarthCurrent.

 

Human Journey

Alyson Foster works in the National Geographic Library where she purchases books for the Library’s collection and assists NG staff with finding research materials.