Evolution: why are there still monkeys, apes, chimps, etc.?

No it doesn’t. It happens one population at a time…

What John most likely meant was that it would have been more correct to say “today’s monkeys are not exactly the same species as the monkeys which we evolved from”. Anatomically, they were likely very similar (though there would nevertheless necessarily be differences), but they were still not the same species, just as today’s crocodiles, similar though they may be in appearance to their ancestors, are not the same species as those ancestral crocs.

That would unnecessarily discount the possibility that those early apes where held in a slaver stasis field until the birth of DaVinci. :wink:

It should be noted that, in general, the other species doesn’t “still exist un-evolved”. Either the old species is replaced by the new species (i.e., the ancestor goes extinct), or the new species was an off-shoot of the old species and ventures off in a different evolutionary direction, while the “parent” species continues to evolve separately.

We are monkeys, and we are apes. It’s just that, due to differing environments and selection pressures among isolated populations, the offspring and decendents of some generic proto-monkey have currently evolved into several different kinds of monkey, including chimps and people.

In other words, apes and monkeys still exist because we haven’t gone extinct yet. But man, we’ve all diversified over the years.

Evolution is the change in animals due to environmental pressures. Where certain traits are useful for survival and reproduction, over the long term those traits come to dominate. So some locations select for tall and thin (the tribesmen on the plains of Kenya) and some select for shorter (pygmies in the Congo jungles).

The same as for the giraffe, for example - the taller ones had better foraging during the dry season - they could reach the higher leaves. Over time, they out-survived shorter ones. When you’re talking a million years, you can adapt quite a ways.

So each ecology has “niches” - an area food source etc. that is usable. If these is food going to waste, some animal will eventually find and exploit that food source, and then it’s a race to determine who is best suited. If some apes come out of the trees to exploit discarded lion kills that still have meat (protein) then the ones best able to run back to the trees will survive. The ones who can stand upright will see enemy approaching sooner, etc.

If a group eventually changes too much, they have trouble mating with a branch of the old group that has not had the same adaptions. So the ground dwellers don’t usually mate with tree-dwellers; their offspring would be not as good at either food source, by climbing or running. The animals drift apart.

We can see in the progression of sea otter, seal, whale the return to water was advantageous for some animals. If you eat fish, being able to chase it a ways into the sea helps; adaptations for sea make life on land less easy, so you stick to the shore. Etc.

Tigers are solitary hunters in the jungles, exploiting the larger jungle animals. Lions are, oddly, a herd-like cat family, adapted to chasing down the herd animals of the African plains.

The problem is, with every advantage comes a cost. Big animals (mammals) need more food just to stay alive. In times of scarcity, they get weak and die first. So there’s an optimum size for an animal in a niche, depending on supply and reliability of food source. really fast (like the cheetah) means you can run down your prey; but to win with speed you have no room for excess weight like fat reserves. Your range is limited to places with reliable food sources. A camel may have distinct disadvantages protecting itself against wolves, for example, compared to horse hooves or cattle horns. But in the desert, it can outlast most predators easily.

I read somewhere our brain consumes about 1/3 of the calories we need to stay alive. So it better provide a significant advantage in our survival. Obviously, for a few million years it has.

Small monkeys live in jungle trees and eat fruit. Madagascar had no such animals; millions of years ago, some lemurs must have survived being washed out to sea to Madagascar. Now they occupy that niche, and many others on that island. Places like New Zealand, or Mauritius, with no natural predators giant birds evolved to be flightless grazers. Adding humans, cats, or foxes to the islands created a predator they had no time to adapt against, and they either disappeared or are close.

Evolution is nature seizing an opportunity. Animals best suited for the opportunity will exploit it, and any offspring even better adapted will dominate that opportunity, and so on.

Crocs and cockroaches have not changed in tens of millions of years because their niche has remained the same, and no animal has arrived that could exploit that niche better. Where food sources disappear for months at a time, like the Nile, cold-blooded has a distinct food advantage over warm-blooded who need a feed daily. Cold-blooded is less of a disadvantage in the tropical water than on dry land where temperture fluctuations could leave a cold-blooded animal vulnerable while cold and sluggish. (Most reptiles nowadays are either water-based or hide themselves at night).

I’m not sure why anyone is trying to give a real answer to the question. Questions like that are either deliberate baiting, or show such a profound lack of knowledge and reasoning that it is pointless to respond.

Meh, the OP seemed genuine enough and didn’t start vehemently denying the responses so I don’t think that’s a completely fair assessment.

Ignorance isn’t fought by telling the ignorant that you think they’re too dumb to help.

Ditto. The first thing I did when I read the question was check the OP’s join date. Real baiting questions and drive-by trollings usually come from newborn guest accounts, and read something like “yeah well if u athists are so smrt, explain what worth is half an eye, yuk yuk yuk”.
That one seems like your run of the mill idle and honest curiosity born of a vague understanding of the principles of evolution. Keyword being vague, obviously - but that’s what the Dope is for.

Well, that and ambiguity. Maybe.

You can call me dumb all you want, but I’m no troll. I know you didn’t explicitly state either of those things, but we know what you’re getting at.

If you must know, the question came from one of those ridiculous Kirk Cameron videos I think. When it was posed, I knew it was a question that was not really founded in logic, but I had no definitive answer for it myself. I asked here in GD because I can see a mod moving it from there to here anyways due to the “controversial” nature of evolution with some people. In addition to my own theories, which have been validated by a few of the posts, I have also learned quite a bit. That was my intention.

Thanks guys.

I too enjoyed pondering the evolutionary miracle that is the banana! :slight_smile:

We are not yet using IQ tests or the SAT to determine who may post on the SDMB. Unless you have knowledge of any given poster’s intelligence and education, you are probably not qualified to determine that poster’s intelligence. The whole point of the SDMB is to promote knowledge, so it would seem to me that responding with facts and logic is exactly the way we should address such posts, rather than dismissing the posts or the posters.

Anyone who has ever been in a fundie church or known people like that, is used to the idea of evolution is a lie and you cannot beleive it, no matter the proof. Its nice to see a thread here (fighting ignorance!) discussing the facts in a logical and calm manner. As one who has recently come out of that kind of mindset, its nice to read.

Sorry, I can see now that you are honestly asking for an answer. I’m curious though, what did your school teach with regards to evolution? There are lots of details that I know they don’t have time to get into, but this is pretty basic stuff they should cover. Did they think it was too controversial?

I’m not sure why the OP’s question would be confusing. Even if humans did evolve from an existing primate species… so? They didn’t change, but we did. What’s the problem?

Through High school there was not a whole lot of time spent on evolution at all, but it was covered at least a little. This is in Ohio, so there was no controversy per se. My Anthropology intro class at OSU was taught quite well I thought, but we didn’t come close to addressing such off the wall questions such as the one posed here. I understand selective pressures, we all heard the story about the black and white moths and the soot.

Had you asked me back then “Why do monkeys still exist if we are supposed to be a more evolved version” or something similar, I would have said “Monkeys do well in their environment, and humans do well in theirs, neither would last long in the others though”. Since that’s not nearly a complete enough answer for my taste, I asked here, knowing I’d get a much more specific and better worded answer.

This is exactly why I recommended that the OP read a book or visit talkorigins. He or she asked a very basic question (and has given no indication to this point of any intention but checking on what he thinks is the answer to it) and people start nitpicking on correct but naturally incomplete answers. Clearly your long post is correct, but is it really the way to get someone hazy on the basics started?

When I write a paper I put in all the ifs and except fors and as far as the data indicates. That may not be the best thing to do in this kind of thread.

Whether or not any of our direct ancestors actually fall into the category of monkey, the average person will consider monkey to include those species called monkeys today - none of which were our ancestor. The 100% correct explanation is the enemy of the good explanation.

Did you get a satisfactory answer?

The reason I suggested a book or the talkorigins site is that a thread like this is a terrible way of learning anything. In a book everything gets presented in a logical order. That is like a good teacher in front of a room giving a well prepared lecture - this is like trying to learn in a roomful of experts.

Question from a blind man: What color is grass.
Person A: grass is green.

Person B: Except in a drought where it turns brown.

Person C: Except when it gets too little nitrogen when it turns yellow,

etc. Our blind person leaves totally confused, while the experts congratulate themselves on their precision.