U.K. duo suggest early humans retained fine hair to ward off parasites

[Tank]

U.K. duo suggest early humans retained fine hair to ward off parasites

This is the whole article as it's quite short.

(PhysOrg.com) -- Evolutionary biologists have long been puzzled by the question of why human beings have retained body hair. Most agree that changes to the fur that our ancestors sported came about as a means to keep cool in the hot African climate. So why then, didn't we just lose our body hair completely, instead of having it change from long thick fur, to short and thin hair that makes us look like we're mostly bald all over anyway, when actually, we still have just as many hairs as we ever did? Isabelle Dean and Michael Siva-Jothy think they've figured it out and have published a paper in Biology Letters explaining how they believe it's all about warding off skin parasites.

Suspecting that having fine short hair, rather than no hair at all would help us detect the presence of skin parasites such as bed bugs, the two set up an experiment using volunteers from the University of Sheffield where they both work, to find out. The volunteers were made up of ten women and nineteen men each of whom had one small square on one arm shaved for testing. Hungry bed bugs were then dropped onto the bare skin to see how long it took the volunteer to feel its presence. Also timed was how long it took the bed bug to pick a spot for parking and eating. The bugs were removed just before they bit. The same experiment was performed on each volunteer on the other unshaved arm as well to provide a way to compare results.

After tallying up the results afterwards, the researchers found that more hair causes bed bugs to take a lot longer to find a spot to eat, which makes sense because all those little body hairs make the trip more difficult. Sort of like the difference between us humans walking down the street or wading through a dense thicket. What's perhaps more surprising, but maybe shouldn't be, is that the volunteers all took much longer to feel the bug crawling on their skin on the shaved patch, then on the unshaved arm, indicating that the presence of fine hair helps us to feel such parasites on our skin and to get rid of them before they can begin biting us.

Not surprisingly, men were better at detecting bed bugs on the unshaved arm, due to having thicker and longer hair than women. As to why men are generally hairier looking than women, the researchers suggest it might be due to something as simple as women preferring men with fewer parasites on them, which would imply more hair.

So I'm not very hairy anymore, I'm very parasite proof 

[OldGit]

I feel we also need to consider the role of fire in this context. Let us not forget that primitive man was the only creature to sit round a campfire and toast his caterpillars or hedgehogs, whatever, on a long thorn twig. In doing this, the hairier specimens would catch fire and leap madly around the savannah shouting "Ug!". Thus was language born, and thus it was that the less hirsute individuals survived to breed. Furthermore, females would mate preferentially with smooth cavemen because they knew the hairy ones were more likely to catch fire and be unable to support their offspring. And now the female dislike of hairy blighters is inborn, except for pop stars, which didn't exist on the primitive savannah.