Who do guys have more hair then women(facial hair), why do we yawn, and why don't animals laugh like humans do?

1. Why do guys usually have more hair then women, what purpose does it serve? Is it made for fighting/to show dominance like a lion's mane? And if it is beneficial in any way then why don't women have it.





What purpose does yawning serve and why do we get the urge to yawn when we see someone else do it?





What purpose does laughter serve and why don't animals laugh? (hyenas don't laugh it's just a noise they make)Who do guys have more hair then women(facial hair), why do we yawn, and why don't animals laugh like humans do?
1. Testosterone makes hair. Not sure if there is an evolutionary mechanism there.





2. You yawn because your body wants oxygen. Trigger reaction to get you to take a huge breath of fresh air. Your breathing slows when you are tired.





3. Primates laugh. As for purpose... good feelings?Who do guys have more hair then women(facial hair), why do we yawn, and why don't animals laugh like humans do?
Most male animals have more '; adornment'; or ';ornamentation'; on their bodies., like the male lion's mane ,or the brighter colours of male birds. It supposedly evolved in order to attract mates.As we evolved higher and developed culture, women are not necessarily attracted to facial hair, as what we are attracted to is mostly culturally determined,now. Also,in the wild, facial and body hair on males and breasts and body hair on females signaled to potential mates that the individual was ';of age'; for breeding.


On yawning, the jury is still out. The stock answer is because the brain senses a need for more oxygen. But why would I need more oxygen just because smeone else yawned. The answer again may lie in evolution. Possibly, when a group of proto-humans were in an enclosed space, like a mud hut or a cave, when one person needed air, others would also so the yawn became contageous. But I really dont know how it could become so acute that it became a survival characteristic. If the air was bad enough to affect survival, no amount of yawning would save them from suffocaton.


It is said the reason someone feels like puking when they see someone else vomit, is that it was a defence against food poisioning where meals were shared communally. If one person ingested some bad meat, then it's likely the others did, hence contageous puking.


AS for laughing, one needs some kind of higher intelligence to appreciate humour. Animals just aren't smart enough.
Haha! It would be creepy if they laughed.. LOL





1. Testosterone. Because since guys were always the ones out hunting they needed that extra protection from the elements. ';Cavemen'; had much thicker hair.. men today actually have evovled to have WAY less.





2. Yawning.. Many people assume that we yawn because our bodies are trying to get rid of extra carbon dioxide and to take in more oxygen. This may make some sense. According to this theory, when people are bored or tired, they breathe more slowly. As breathing slows down, less oxygen makes it to the lungs. As carbon dioxide builds up in the blood, a message to the brain results in signals back to the lungs saying, ';Take a deep breath,'; and a yawn is produced.





3. Because they have the most basic of emotions. Laughter is a bonus but not a necessity for survival. Animals simply never developed this trait or emotion because they do not need it for they could never grasp the concept of humor anyways...
Hair, I don't know.


It has to do with hormones, but I don't know why the hormones cause excess hair sorry.








Nobody knows for sure what yawning does, scientists have proven it doesn't get any more air to the brain than simply breathing.


We yawn when others do because it is our brain trying to ';blend in'; and we do it to get on the same ';wavelength'; as their brain to understand their conversation better, even if we aren't in conversation. I am yawning now thinking about it.








Animals laughing, no bloody clue:P


I think people learn to laugh however, because babies can't laugh, and babies that are in depressing environments with no laughing, do not know how to laugh untill they leave,
1. testosterone causes facial hair.


2. Yawning is to get more air in your lungs, it's possible that you're brain remembers to yawn when you see someone else do it


3. Laughter, just to show feelings, i guess. maybe it's just an evolutionary thing where we got laughter before evolution decided it wasn't needed
I only know that people yawn when they need oxygen. If you notice when you yawn, you get a full deep breath. Sorry I don't know anything about the rest of your question.
I would love it if they laughed
because we enjoy shaving. because it`s fun. beats me.