Does everything evolve at the same rate?

I am trying to understand the evolutionary concept. If there is an animal in which monkeys and humans evolved from, wouldnt there be more and less evolved humans/monkeys? Where are the slightly less evolved humans? Why are we all the same? I cant bring myself to believe that there is a whole group of animals. Millions of them. They evolve through mutations, or whatever be the case. Yet somehow they all evolve at the same rate. And if only a few actually mutate and evolve, why would all the others just die off? Other the millions of years of evolution, it seems quite impossible that all humans are evolved the same.

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the answer is , depends WHEN you look ,there is good evidence of homo sap. ie us , co exsisting with other homo species , ie neadathals , in the past , but we have proven the more durable and adaptive homo line , the others have died out .similar events will have effected monkey and ape lines as well , most commanly the older species will survive in a more isolated area , australia is a good example of very old species which have not changed and not given rise to newer lines .And no evolution is not a even paced system the rate of change depends not only on mutations occuring , but the mutation being advantagous over the rest of the population , thus more individuals with the mutation surviving . Often it is an enviromental change which will make an exsisting mutation become an advantage , drier , weter, colder etc will lead to a evolution event in a population .in a given population there will be a wide range of differences , but these will have little to no effect in a stable enviroment . However a new mutation may give rise to a more advantged group with in the population and , over time these may become the dominate type and even giving rise to a new species .one thing to remember you can have populations of the same speices living some distances apart , and one grp may change to become a new species while the other remains the same .

No, things don't all evolve at a set rate. If they did, ALL sepcies would be the same. I'm not a big fan of the idea of a "rate" of evolution, but evolution tends to "speed up" under severe environmental pressures. For example, if you have a species with plentiful food, no competition within the species or with other species, that organism will have no "environmental pressure" to evolve, and that species will "stagnate". Sorry to use all the apostrophes!
Take the koala. It feeds on eukalyptus. Lots of it. In fact, it is pretty much the only animal that eats it. It has evolved to monopolise a food source. It's ancestor would probably have had a much more varied diet, but it became advantageous to eat eukalyptus leaves. However, this gives the koala a problem as a species. If the eukalyptus dies out (for whatever reason), then so will the koala.
There is archeological evidense that similar things happened to sub-species of humans (the Boisiae, but I've certainly not spelt that correctly).
Evolution is dynamic, and it happens (and is still happening) over millions of years. We don't have a time machine, so its more or less impossible to say things like "at this point X became distinct from Y" but we can make good guesses.
Sorry, I've gone on a bit of a rant. Now finished!

Ok, I admire your post, but it doesn't answer my question. You are just assuming this happens. Sure, you have one species of animal that thrives in a very medium temp. enviroment. You split this species in half. One half goes to a very hot climate that it can survive in, but barely. The other half goes into a very cold climate it can survive in, but barely. Over many years these groups will differ greatly. The animals with white hair, and more hair will survive better in the cold. The opposite will happen in the hot. Survival of the fittest. In many years, some people will look at the cold group, and the hot group, and see how very different they have become. YET, if you take the two groups, and put them back together into a medium temp. climate, eventually they will be just as they were. They will still be able to reproduce just as before and everything will equalize again. They will never evolve into a different species. All that will happen is the individuals which have superior genes for the givin enviroment will thrive in that enviroment. Natural selection has nothing to do with evolution. Natural selection is a very observable fact. Evolution is only a belief.

It seems to me that in this case you are just assuming this is what would happen. This is certainly a viable outcome for the scenario but there are other possible outcomes where the course of natural selection has led to a situation in which the two divergent populations either choose not to mate or are physiologically incapable of breeding together successfully. Unless you can show some barrier to these options then there are also possible outcomes. Both genetic/physiological incompatibility and pre-mating isolation have been traced to a genetic basis in some instances.You may claim that such barriers cannot arise through mutation and natural selection but people will need more than just your authority to go on. Is there any actual scientific reason why seperate species could not result from your scenario?TTFN,WK

Whether or not they would reproduce is not the case. They would be able to reproduce. And that wasnt the point of the post anyways. The point is, what I stated is an observable fact that I hope everyone would agree on. Because we see natural selection happening today. But, the belief that they could evolve through mutations and what not is just a thought. I believe in creation, but that has nothing to do with what I am posting. I am trying to understand why people even believe in evolution when it makes no sense. There has never been any fact in evolution yet somehow so many people believe in it because a few guys a while ago brought it up in some fantasy. I just cannot understand how people believe in evolution.

This is pure assertion. Rubbish, we see mutations arising all the time. So since we see mutations arising and we see natural selection in operation your entire case seems to be based on the fact that we haven't observed millions of years of evolution in person.Perhaps if you actually read some scientific literature you would find the evidence which you claim doesn't exist. So not only do you not know anything about the theory of evolution but you also know nothing about its historical development. You seem to be speaking from a position of almost complete ignorance, maybe it is just how you choose to express yourself but it comes across as if you hardly have the first idea what you are talking about.TTFN,WK

While them being able to reproduce is an assertion... it is something we could test.As far as mutations. I believe in mutations. Does that mean that some mutations help out animals? If something is mutated, and it reproduces, does it pass on the mutation? What is a good mutation?What is some proof of evolution? There is no more proof for evolution than there is for any other belief. It is all just speculation. You argue with me, but give no facts. I am just posting the reason that goes on in my head.

Yes. Some mutations are beneficial in particular environments. One common example is the mutation leading to sickl cell anaemia. While homozygotes for SCA, those with two mutated copies of the beta-globin gene, suffer from debilitating SCA and have a greatly reduced lifespan. Those homozygous for the sickle cell causing gene may suffer some mild SCA related symptoms but have a normal lifespan and also have an increased resistance to malaria over those with 2 wild type beta-globin genes. See this page from a molecular biology textbook for more details of the molecular basis of SCA and a description of mutations in general.There are also a range of other mutations which can interact with the sickle cell mutation to ameliorate its effects. As long as the mutation is represented in its germline cells then the answer is yes. Most people will have a number of mutations in their somatic cells, which may lead to cancer among other things, but these are not passed on. In evolutionary terms a good (or beneficial) mutation is one which serves to increase the reproductive success of an organism. If a mutation leads to an organism having more fertile offspring than an organism lacking the mutation then it is said to be beneficial. This depends what you mean by evolution. There is considerable proof for mutations arising producing differential fitness which can be actd upon by natural selection, if you like I can provide a number of references. If you mean something more than mutation and natural selection acting on a population to change its genetic makeup then it would help if you were specific as to what you think requires proof.TTFN,WK

And if the test came back saying they couldn't reproduce then would you have evidence for speciation having occurred?TTFN,WK

This seems to be deviating somewhat from your initial topic on evolutionary rates, some of these questions might be better addressed at the Mutations Made Easy thread.TTFN,AW

using your example if you put the two population back in the med temp , they may well revert , BUT they may not , the cold population may have other genetic factors which make it better than the hot population and so it may be the cold varient that dominates , or the other way round , OR mixing the hot and cold populations produces a even better suited varient to live in the med temp , a totally new population .evolution is NOT a belief , its a scientic theory , and as such seeks to explain the given facts in the best fitting way it can , it is open to review , reinterpitation , and change , its a work in progress , and it stands up to its challengers very well .no other theroy can produce such a body of positive evidence , of fits the data as well .

I suggest you do some reading on ring species. That they exist pretty much refutes your reasoning.

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YET, if you take the two groups, and put them back together into a medium temp. climate, eventually they will be just as they were.

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I know this is a purely hypothetical situation, but that is a big assumption. Evolution isn't like a piece of elastic. Just because you relieve the pressure, it doesn't mean everything will spring back into place.
Whether they revert back to their original forms would depend on environmental pressures. Your situation states that they are none, why would there be any need for change? You also need to consider the lengths of time involved.
Also, remember the definitions of a species and genus:

• Two members of the same species can breed and produce fertile offspring
• Two members of the same genus can breed but the offspring will be infertile (eg horse + donkey -> mule)
  

Thanks for making the destinction between natural selection and evolution though. Not that many do.Edited by Whirlwind, : Bad grammer