Explain the evolutionary advantage for human beings to lose a thick coating of body hair.?

If you believe in the theory of evolution as an explanation for the origin of mankind, why would evolution take away an advantage (remember, its a random series of events over millenia, selecting for the best survival skills among species).



Thick body hair such as the other apes have serves them well as a protective layer - both from climate and injury.



You could justify the loss of facial hair - in order to better see facial expressions. But apes don't have much facial haire either.



And you can't rule in the development of clothing as a cause, because that would come well AFTER the loss of hair as a natural trait (so it would be a response to the effect).



Speculation?



(One point I must make: human beings do have as much hair as apes, its just much thinner, but we do have a comparable number of follicles - so what I'm asking is why, is this hair much thinner, shorter etc. than in the apes? Evolutionarily speaking, that goes counter to natural selection).Explain the evolutionary advantage for human beings to lose a thick coating of body hair.?
Okay, what follows is pure speculation...



If Africa was the cradle of life, and supposing it had a similar climate than it does today, probably thinner hair was an advantage. If the place where the first humans appeared had a hot climate, probably having thick ape-like hair was a disadvantage producing excessive body heat. I know all or most African animals have thick hair, but I believe that in their case it serves the purpose of mimetization, both for predators and prey, but humans weren't neither.



Gorillas and primates also live in Africa, but they inhabit more humid and colder climates like jungles and mountains, so probably thicker hair is beneficial for them.



So in short, our hair turned thinner because it provided too much heat and we had no need for mimetization.



Again, this is all just speculation off the top of my head. There is probably a ';real'; reason based on science or maybe it hasn't been figured out yet.Explain the evolutionary advantage for human beings to lose a thick coating of body hair.?
There is no environmental pressure to preserve the body hair.





If people were running around naked, then the hairiest amongst us would have had best chance to survive the winters - and therefore to transfer our (hairy) genes to the next generation. Given that we took on wearing clothing long time ago, the warmth the body hair provides became irrelevant to our chances for survival.
How comfortable do you think you would be having that thick hairy coat under your clothes? Yes, once humans got intelligent they started making adn wearing clothes - so that they could be comfortable in ANY environment. A full coat of natural body haid is not very compatible with that so we lost it.
this are a good one. Think back to about 3.5 to 4 million years ago in East Africa. The land was verdant and full of trees. Geophysical upwelling about that time in that area converted (over time) the area full of trees to more rocky, arid landscape. Grasses grew tall but our ancestors couldn鈥檛 climb grasses so they were eventually forced onto the surface. This caused several major changes in hominids; one being they were forced to stand often to see over the tall grasses and this new posture allowed an elongated laryngeal instrument making more complex sounds possible and eventually...speech. The land was more arid and therefore had less water. A tall physical form with little body hair uses less water, a commodity now in short supply.



So, bipedalism was required both for the elongated larynx and the eventual loss of body hair. Who woulda thunk that geophysics were at the bottom of hairless bodies and Shakespeare?



Finally, it is not necessary to ';believe'; in evolution. nor, is it necessary to ';believe'; that 2 plus 2 equals 4!
A few possibilities:





As humans evolved into upright hunters, they started spending more time in warmer, open spaces. Less body hair allows for more efficient sweat evaporation and faster regulation of body temperature.





Hair provides a great environment for parasites which carry diseases like malaria and lyme disease.





Loss of hair is often associated with increased time in an aquatic environment. Hair increases water resistance and is a poor insulator in water. Early humans may have relied more extensively on the shores as a food source.