Some questions about evolution

[Sasune]

Where is the missing link?
If we evolved from apes, why are there still apes?
Why haven't we seen apes evolve?
If we have a lot in common with rats and pigs, did we evolve from them too?
What evolutionary purpose does pubic hair serve?
What about puberty?

[VorpalNeko]

Sasune

Where is the missing link?

What makes you think a link is missing? What does "the missing link" even mean, to deserve such a singular article?
If you mean a transitional fossil, those are around by the buttload.

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If we evolved from apes, why are there still apes?

There are two relevant definitions of the words "ape". Look it up. Depending on the definition you want to use, one of the following questions are very analogous:
1) "If Australians came from Europeans, how come there are still Europeans?"
2) "If pitbulls came from dogs, how come there are still dogs?"
And yes, this question is exactly as silly as those two. But more to the point, humans did not evolve from any current species of ape or monkey, and no competent anthropologist or biologist ever claimed they did. And taxonomically, humans are apes.

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Why haven't we seen apes evolve?

We have, if "seen" means "observed".

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What evolutionary purpose does pubic hair serve?

To make your genitals smellier. And while this can range from "blarggh" to "sexy", it would've been more important throughout most of history, where people in general were much smellier in general.

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What about puberty?

The benefits of delayed sexual maturity should be obvious. Being able to conceive children as a toddler would just end horribly, for example.

[Sasune]

VorpalNeko

Sasune

Where is the missing link?

What makes you think a link is missing? What does "the missing link" even mean, to deserve such a singular article?
If you mean a transitional fossil, those are around by the buttload.

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If we evolved from apes, why are there still apes?

There are two relevant definitions of the words "ape". Look it up. Depending on the definition you want to use, one of the following questions are very analogous:
1) "If Australians came from Europeans, how come there are still Europeans?"
2) "If pitbulls came from dogs, how come there are still dogs?"
And yes, this question is exactly as silly as those two. But more to the point, humans did not evolve from any current species of ape or monkey, and no competent anthropologist or biologist ever claimed they did. And taxonomically, humans are apes.

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Why haven't we seen apes evolve?

We have, if "seen" means "observed".

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What evolutionary purpose does pubic hair serve?

To make your genitals smellier. And while this can range from "blarggh" to "sexy", it would've been more important throughout most of history, where people in general were much smellier in general.

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What about puberty?

The benefits of delayed sexual maturity should be obvious. Being able to conceive children as a toddler would just end horribly, for example.

What I meant about puberty is, why do we break out in acne etc?

[VorpalNeko]

Sasune

What I meant about puberty is, why do we break out in acne etc?

I don't know, though if I were to take a wild guess at it, perhaps acne is just a side effect because the oil glands are similarly kick-started by testosterone as the pituitary glands, even though they're not needed. Not everything needs an individually positive reason; some things are just side effects of other things. But again, that's more of a guess than an informed opinion.

[Layra-chan]

Sasune

What I meant about puberty is, why do we break out in acne etc?

Adolescent acne comes from the increase in testosterone; the follicular glands secrete more sebum, which clogs follicles and results in acne.
In fact, a lot of puberty can be blamed on the increase in testosterone. Some of the effects, such as muscle growth and the development of the reproductive organs, are probably the main reason why the testosterone increase happens, and some of the effects, like acne, are just side effects that aren't bad enough for humans to switch to a different chemical.

[scintiller]

Sasune

Where is the missing link?

there are multiple intermediate species from things from fish to land mammals, dinosaurs to reptiles, and reptiles to birds that have been discovered. There are some mildly disputed intermediate species between our most recent ancestors and humans.

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If we evolved from apes, why are there still apes?

Think of evolution as a multibranched tree. Apes are one branch just as humans are, each species will have their own branch, and things aren't necessarily evolving to become more like a higher order (ie. apes to humans), but an emergence of a new species occurs from genetic mutations that get passed over thousands to millions of years before a new species is required to describe and organism.

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Why haven't we seen apes evolve?

Apes have evolved from their lower forms but there are some 'living fossil' type creatures too that have evolved very minimally and some organisms even seem to 'reverse evolve', for example, whales used to be land dwelling creatures but are now ocean bound once again.

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If we have a lot in common with rats and pigs, did we evolve from them too?

We share their DNA, not saying that humans were once pigs, but that's the wrong way to think about it, we've basically evolved from most older species, even fish and all of those sorts of things, if you want more proof, just look up evolutionary similarities and compare embryology smile

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What evolutionary purpose does pubic hair serve?

We evolved from hair covered creatures and there are some remnants, there is probably no actual purpose for it (that I know of neutral ) but it's still there.

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What about puberty?

Puberty is just a series of hormonal changes that causes some adverse effects but it's how we grow and junk biggrin

^^^ just finished an evolution class, so I hope that that helps.

[Sasune]

scintiller

Sasune

Where is the missing link?

there are multiple intermediate species from things from fish to land mammals, dinosaurs to reptiles, and reptiles to birds that have been discovered. There are some mildly disputed intermediate species between our most recent ancestors and humans.

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If we evolved from apes, why are there still apes?

Think of evolution as a multibranched tree. Apes are one branch just as humans are, each species will have their own branch, and things aren't necessarily evolving to become more like a higher order (ie. apes to humans), but an emergence of a new species occurs from genetic mutations that get passed over thousands to millions of years before a new species is required to describe and organism.

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Why haven't we seen apes evolve?

Apes have evolved from their lower forms but there are some 'living fossil' type creatures too that have evolved very minimally and some organisms even seem to 'reverse evolve', for example, whales used to be land dwelling creatures but are now ocean bound once again.

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If we have a lot in common with rats and pigs, did we evolve from them too?

We share their DNA, not saying that humans were once pigs, but that's the wrong way to think about it, we've basically evolved from most older species, even fish and all of those sorts of things, if you want more proof, just look up evolutionary similarities and compare embryology smile

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What evolutionary purpose does pubic hair serve?

We evolved from hair covered creatures and there are some remnants, there is probably no actual purpose for it (that I know of neutral ) but it's still there.

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What about puberty?

Puberty is just a series of hormonal changes that causes some adverse effects but it's how we grow and junk biggrin

^^^ just finished an evolution class, so I hope that that helps.

Okay, thanks for taking the time to reply. But why do we go through hormonal changes during puberty? Someone earlier explained how, but not why. I want to know why humans are the only ones that do this.

[Tuah]

Sasune

Why haven't we seen apes evolve?
If we have a lot in common with rats and pigs, did we evolve from them too?

I think everyone else has covered the other questions well enough, so I'll address these two.

First off, a single animal does not evolve. Societies of animals evolve. And we see evolution happen every time a new ape is born; that ape's DNA is a mix of its parents', and will have an impact on that ape's life. If the DNA provides good characteristics (high strength, resistant to weather, whatever), that ape is more likely to survive long enough to have his own children.
These tiny differences add up over time, and can even be unrecognizable from the one that came generations before.

This is why you'll see such differences in humans from around the world. Different societies stayed separate for many years; long enough to even bring obvious, visible differences. But we're all still humans because we didn't stay separate long enough, and our societies intermingled while they were still compatible with each other. If our societies had continued to stay separate for tens of thousands more years, we would likely have become different species - unable to reproduce because our DNA doesn't match up.

Hence why a horse can breed with a donkey, but not, say, a deer.


This is also why we have a lot in common with rats and hamsters. We did not evolve from them, but alongside them. We shared a common ancestor - a society of some kind of mammal split into different societies, and those different ones developed on their own. Hamsters, rats, and humans (and other apes for that matter) evolved from that ancient mammal; not from each other.

[rider91]

Sasune

Okay, thanks for taking the time to reply. But why do we go through hormonal changes during puberty? Someone earlier explained how, but not why. I want to know why humans are the only ones that do this.

its a part of how our body grows and matures physically and mentally for the rest of life, and humans arnt the only ones that go through this, if you observe other mamals as they grow, there will be the one point in time where their behavior changes from child like to seemingly more mature or dominante, its their speiceis own form of puberty

[scintiller]

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Okay, thanks for taking the time to reply. But why do we go through hormonal changes during puberty? Someone earlier explained how, but not why. I want to know why humans are the only ones that do this.

honestly, i don't have an actual scientific answer for you
but my most educated guess is that all species go through some sort of growth and development, but we have a longer lifespan than most and we change more significantly and the hormones are responsible for growth (like within the pituitary gland which I'm sure you've heard of!) and it just creates some adverse effects that may not be displayed (or at least in the same way) on other creatures.

[VorpalNeko]

Sasune

Okay, thanks for taking the time to reply. But why do we go through hormonal changes during puberty? Someone earlier explained how, but not why. I want to know why humans are the only ones that do this.

(Emphasis mine.) That's not even remotely true. It's probably harder to find a mammal that doesn't undergo puberty than it is to find fifty examples of ones that do. And not just mammals. (Exceptions exist. There is this one small creature that's even born pregnant, but for the life of me I can't remember the name.)

For example... ever notice how cats can go into heat? And that kittens don't? Yeah: cat puberty.

[Shokushu]

Sasune

Where is the missing link?

Kind of an outdated concept. If you're talking about between man and ape then we've found around twenty links. It's easy to always complain and keep demanding a new link between any two of them- but by now we've cut the gap into a bunch of small gaps that aren't big enough to really be an issue.

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If we evolved from apes, why are there still apes?

Well you know that dogs come from wolves right? We fed and tamed and bred them for thousands of years- the dogs that is. We didn't have to first round up all of the wolves on Earth before we could do this.

No, instead we just took a few now very ancient wolves. The ones that lived with us eventually became modern dogs and the ones that didn't became modern wolves.

So as for apes we've got the same thing going on. A few specific apes down in Africa started to live in a new way. They went on to become modern humans while the apes that did not went on to become modern chimps, bonobos, orangutans, gorillas, etc.

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Why haven't we seen apes evolve?

Actually we've seen them evolve in lots of other ways. One example would be that chimps are developing more childlike faces when they are adults, so that they look young. Sort of like how a lot of humans wear makeup- but only a little.

Now, there's another issue with this. You need to be careful to not view evolution as if it were a ladder. It's not as if we climbed higher while apes just stayed where they were.
Instead think of evolution as a tree. We climbed up one branch, chimps climbed up a different branch. Bacteria climbed up a branch way on the other side of the tree. Everything alive today climbed up some branch and is right at the tip of it. The tree will grow and things in the future will climb out a little further, or sometimes a branch will split and one species will become two.

Simple enough right?

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If we have a lot in common with rats and pigs, did we evolve from them too?

In the same sense that we evolved from apes, yes.
Now to be specific about it we didn't evolve from mice. We evolved from some very distant ancestor that we both share. It was probably a lot like a mouse, certainly would look more like a mouse than a human.

Shortly after the dinosaurs died out the mammals started to branch out into a lot of niches. Again, it's a more of a tree than a ladder. From that mousy ancestor we got a bunch of branches for like rabbits and pigs and monkeys and cats and so on. It all spread out real quick- our ancestry doesn't go through most of those- really just monkeys, apes, and then early man (and early man spread out lots too- we've got a bunch of cousin groups that died out early, not just a bunch of steps we go straight through.)

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What evolutionary purpose does pubic hair serve?

I would guess that it helped to spread pheromones. It helps sweat to evaporate into the air (you could try shaving yours off and then go work out for a bit to really see the difference,) but on the groin the springy hair does serve to act as just a bit of a cushion.

Might not be the reason we evolved it in the first place but you could go put this into google and see what else pubic hair does.

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What about puberty?

Well it's handy, that whole passing on your genes thing.
But a little less sarcastic- we don't pump out sperm and eggs as babies because these are kind of expensive energetics wise. Historically there has been a high risk of starving to death as a child so not turning those things on until you can use them makes perfect sense. A lot of the other differences (growing breasts, different smells, etc,) help others to see that you've entered that age, cause it's kind of a waste (and almost certainly harmful in every case,) to go having sex with young children.

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What I meant about puberty is, why do we break out in acne etc?

It usually goes away once your body has matured so there's not a lot of pressure to make the process prettier. The bacteria don't necessarily play nice either, it's just that our body can do a better job of keeping the nasty ones out after the growth spurt is complete.

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I want to know why humans are the only ones that do this.

Oh other animals have all kinds of nasty problems. You just don't hear about it much because nobody gives a s**t about the self esteem of mice.
Plus there aren't all that many animals as long lived as we are and the vast majority of them grow up in two or three years instead of almost twenty. Now why we take so long to do it is a whole nother story and we might not know all of the factors that went into it yet.
(Feel free to PM me if you want me to just about write up a dissertation on the subject :b )

[Snake Oil Salesman]

There is no missing link. There is a clear evolutionary history.

We did not evolve from apes. Human ancestors were certainly more apelike, but were not actual apes. Humans and apes diverged and evolved separately.

We have seen apes evolve. It takes an extremely long time, though. There were apes millions of years ago, who eventually evolved into modern apes.

[Suicidesoldier#1]

We evolved from squirrel like things.

One went one way and got longer arms and legs and a shorter nose and started eating fruit and the other got smaller with a longer nose and shorter arms and legs and ate nuts.


Kept the bushy tails until recently.

Look at baboons, bushabies, even finger monkeys, crazy stuff really.


We evolved more or less from shrews.

[Snake Oil Salesman]

Suicidesoldier#1

We evolved from squirrel like things.

Actually, the Plesiadapiforms, all died out and left no descendents. sweatdrop