evidence of speciation

is there really evidence of the emergence of new species, or is this simply a word-play on taxonomy/classifications?i would like to hear from both sides of the fence, if possible.thank you.

I think that there are circular populations (they change as you go
around the globe such that two species living side-by-side can
be traced back around to a single species)... although maybe
variants would be more accurate than species there.Mules seem to indicate the emergence of reproductive isolation.You have to bear in mind that all current species are at the same
level of evolution as each other, you just have to go further back
in time for a common ancestor.

In lake victoria in Africa 400 species of cichlids (a kind of fish) have evolved from one species in 14,000 years after the lake was naturally damed and cut off from any ocean water source. Now the fish are in fresh water the salinity deteriated with time, and the jump from salt water to fresh water is a big one.There was a lab study with Drosophila (flies) by Diane Dodd and some of her collegues that seperated the flies into two subpopulations. One was given a starch based medium, another a maltose based one. Each were allowed to live on their medium for 1 year. After that time it was found that species isolating mechanisms were already present.Another example are the species isolating mechanisms exhibited between shrimp populations that have been seperated over time by the isthumus that connects North and South America.

This example is widely cited; but the conclusion of 400 new species within that time span is not a necessary conclusion. It remains a good example of inferred speciation, but people should be aware of alternative hypotheses for the timing and sources of speciation in this example. Also, the inference of a salt water to fresh water transition is incorrect.The situation basically is that in Lake Victoria in Africa there is a superflock of more than 500 closely related but distinct species of cichlid fish. Lake Victoria was never connected to the sea, and this is not an example of adaption from salt to fresh water.However, there is geological evidence that Lake Victoria dried out completely 14,700 years ago, leading to the hypothesis that these species radiated in that time from an initial small colonization.There have been a number of alternative explanation for this superflock of species. These include the hypothesis that the lake did not dry out completely, or that fish from an original superflock survived in some river associated refuges.A recent study is:Abstract:The major caution I have for fellow evolutionists is against citing this example as speciation within 14,000 years or so.

(You have to bear in mind that all current species are at the same
level of evolution as each other)so why are apes still around? i thought thry evolved into
us,shouldn't they be extinct now?

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so why are apes still around? i thought thry evolved into
us,shouldn't they be extinct now?

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Is this a question that came to you by yourself or did you get it from somewhere? Do you think you can work out for yourself what would happen? Try this: If there was a chimp Darwin (like in "The Wild Thornberrys" ) then they would ask the same question; "Why are humans still around?"It is always much more satisfying to work out the answer to a puzzle yourself so why don't you try? Also if it isn't your question you're going to learn something about the quality of information you've been fed.

What would you consider as good evidence?

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Now the fish are in fresh water the salinity deteriated with time, and the jump from salt water to fresh water is a big one.

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But don't tell that to the billions of salmon who make that jump every year!

You are correct about salmon: eels, lampreys, and a variety of other sealife are adapted to switch-hitting between salt and fresh water. But a far wider selection of aquatic critters can't do that - even a 10% decline in salinity is enough to kill lots of "stenohaline" organisms - most jellyfish, if I remember correctly, pop like a balloon in fresh water. I'll dig up references this evening if I get the time.Edit to add a link:
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discossion is about halfway down the page under "words of the moment."[This message has been edited by Coragyps, 04-28-2003]