The root of this gender disparity has to do with natural selection. As humans evolved, the overall amount of human body hair diminished. As that happened, humans with less body hair probably became more capable of survival, which, in turn, made it a desirable trait. Males had more power ...
(unless they’ve jumped on the hair-removal bandwagon or don’t grow pubic hair due to a health condition like alopecia ). so, seriously, why do we have pubic hair in the first place? what is the purpose of pubic hair? are there any medical reasons to groom it? below, the results ...
【典例8】 Why do humans have hair on their heads? Most other mammals(哺乳动物) have thick fur(毛)covering their whole bodies. While humans grow small and fine(细微的) hairs on much of their skin, it's much thicker on the top of the head. Scientists say the answers come down to ev...
But aside from this sometimes scruffy body hair, long hair tends to grow only on our heads. The second theory, known as the aquatic ape hypothesis, proposes that ancient humans spent a lot of time in water. Fur weighed them down while swimming, so they gradually lost their hair. However,...
Why do humans have hair on their heads? Most other mammals (哺乳动物) have thick fur(毛) covering their whole bodies. While humans grow small hairs on much of their skin (皮肤), it's much thicker on the top of the head. Scientists say the answers come down to evolution. Humans probab...
Strand of human hair at 200x magnification. Credit: Jan Homann/Wikipedia Why do humans have hair on our arms and legs but not on the palms of our hands and the soles of our feet? It's a fundamental question in human evolution that researchers at the Perelman School of Medicine at the ...
I agree that most of the causes of hair loss are related to heredity along with stress and nutrition. My husband for example, is following the same pattern of hair loss as his father. He also had a stressful job and does not always eat right because he is always in a rush. All of ...
As with mice, humans don’t grow hair in their wrist area, but other mammals like rabbits and polar bears do. When they compared DKK2 condition in mouse wrist skin with the rabbit, they found it in lower levels in the rabbit. “That thing still present in hairless areas is just being...
Our “new” nails grow directly from the epithelial cells of an area called the germinal matrix, but those cells eventually begin to die, leaving behind a very important protein. Believe it or not, that protein is the same one that forms a key part of our hair and skin – keratin! The...
Have you ever wondered what makes moles grow hair? Moles generally appear on body parts in most cases. Hair growing from a mole is not at all dangerous. The most important thing you can do is go for a proper checkup if you’re concerned. Check if your mole changes in size, shape, ...