Human hairs help stop the bed bugs biting

Human hairs help stop the bed bugs biting. Hairy humans do not let the bed bugs bite according to research at the University of Sheffield which shows how hair helps us defend against and detect bloodthirsty invaders on our bodies. Sensitive, fine hairs which cover our bodies allow us to feel parasitic insects on our skin as well as creating a natural barrier to stop them biting us. A total of 29 volunteers braved an experiment which saw them have one armed shaved, and the other left naturally, before hungry bed bugs were placed on their skin. The results, published in the Royal Society journal Biology Letters, showed people with more layers of the longer (terminal) hairs and smaller, almost invisible, hairs (vellus) covering their arms extended the insect´s search for an ideal feeding ground which in turn increased its chances of detection. Experts say because of this, bed bugs and other parasites, including mosquitoes, midges, ticks, and leeches, favour relatively hairless areas like our wrists and ankles. Professor Michael Siva-Jothy, of the University´s Department of Animal and Plant Sciences, carried out the research with Sheffield Zoology graduate Isabelle Dean, who chose the subject for her honour´s project.