The Evolution Of Hair And Fur

Hair and fur The world around us is constantly changing. Not at a noticeable rate. Most things do not noticeably change within a persons lifetime. Things are constantly evolving to fit the environment. Evolution is a “change in the gene pool of a population from generation to generation by such processes as mutation, natural selection, and genetic drift (dictionary.com. n.d.). Evolution allows plants and animals to adapt to the environment and become more efficient. As animals and plants evolve less desirable traits are cycled out and beneficial traits continue to present themselves and overtime may change to become even more useful. These slow changes can be observed by observing fossils of animals and plants before their traits changed.

Hair and fur are actually the same thing. Fur just tends to be more dense than hair. Hair and fur are both keratin, which is also what nails are made of! Some might associate hair with humans and fur with animals. They may also assume that fur does not grow as long as hair. Every mammal goes through a cycle of growing hair. Humans tend to have longer cycles which allows it to grow longer (Hutchinson, 2014) . Hair length is caused by a specific trait (Wong, n.d.). All mammals have hair at some point in their life. Some have a lot and some have a little. Hairs main purpose is to protect our skin. Some have theorized that mammals produced hair/fur originally to protect the body from heat or cold weather. Hair is specific to mammal’s who are also warm-blooded animals. It is uncertain whether hair or warm-bloodedness came first, so this theory is sometimes criticized (Bergman, 2004). Some of the earliest records of hair appear to be nearly the same as modern hair is (Berman, 2004). Hair is a very difficult trait to trace back in time because typically hair does not fossilize. It is assumed that hair evolved from animals with scales (Berman, 2004). The evolution of humans has been closely

There is an interesting theory about why we lost most of the hair primates have. Pennsylvania State’s professor of anthropology, Nina Jablonski believes that humans evolved with less hair to keep their brains from overheating (Connor, 2013). It is believed that the extra energy it took for humans to walk on two legs caused them to overhead, which affected their brains ability to function. Changes in skin tone is a result of hair moving to particular parts of the body. Humans who lived in Africa were exposed to sun more than humans living in Asia and Europe (Connor, 2013). The intense sun over time changed the pigment of their skin and some humans evolved to have darker skin to compensate for the amount of sun. It it hard to say exactly why humans hair has evolved the way it has. It is interesting they the position of hair on the body has changed, but they hair that grows has not evolved. I would consider hair to be an analogous trait, because it is the same in all mammals, the only thing that varies is the thickness. I think that hair would be categorized as convergent, because even though it grows in different ways, it is very similar in all mammals and the hair itself has not