How many generations does speciation take?

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So Joe Lowspermcount is a separate species from homo sapiens because he is unable to reproduce? Are you really saying that?

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Joe Lowspermcount may in fact be a new species. Ma and Pa Lowspermcount could also be separate species. However, individuals do not a species make. Species are a group of interbreeding individuals. One person is not an interbreeding group. Just as a wild, off the cuff, example: If the offspring from a Californian and a New Yorker always has low sperm count then we could consider this as the start of a speciation event. (For the moment ignore immigrations and all that).

Hi custard,The "how" of it is currently a very active area of research. There are too many different things going on to put a number on the generations required for speciation to take place. I suggest you read "Speciation" by Coyne and Orr link to Amazon for one prominent view (within a very diverse set of views) held by evolutionary biologists on this matter. This book is has some maths in it, but not too much, and is highly readable.CheersMickEdited by AdminJar to shorten link.This message has been edited by AdminJar, 03-09-2005 20:21 AM

Answer: 1 to 500 000 generations, mostly 50 000 generations.This is a quantitative question, all previous answers are like drool for someone that wants a fast answer to this forum post!!!!!!!europeans and africans diverged 35 000-50 000 years ago... euros and asians 30 000 years ago... euros and aborigenes 75 000 years ago.75 000 years is 75 x 60 = 4500 human generations.fruit flies have been known to speciate after 35 generations,and fist alledgedly after 20,but sticklebacks have been known to take 1000 generations to just look different but not speciate.bacteria like E Coli evolve slower than us, they seem to not speciate for 100 000ds of generations, perhaps millions of generations. they reproduce by division.As far as we know, we could have fertile offspring with Neanderthals and even Denisovans, who crossed with aborigenes.denisovans split from us from about 1000 000 years ago..that's about 1000 x 60 = 60 000 generations.AFAIK, we could make fertile offspring with a denisovan. of course we cant with a chimpanzee, although i dont know if anyone has tried that much to make a chimpuman. (6mn years divergeance)so you are talking about different genus, differens species, it depends on the complexity of the genome, the robustness of the genes, the reproductive morphology change rate etc.My own gut feeling is that, for a mammal, you can can expext different populations to become distinct after 10 000 to 60 000 generations ON AVERAGE. statistically. of course they day that divergeance occurs, it's only one generation.i cant beleive i joined such a ludicrously named forum, it's unbeleivable that some cultures have people that use hosiptals and chemistry and say the people who invented them are wrong.Edited by toine, : No reason given.

That's not speciation, though, is it?

No, certainly aboriginal and other ethnicites divergeans doesnt amount to speciation!!!I mentioned that to demonstrate that 4500 generations of mammal evolution seems no where near a deviation.just recently i have remembered that reproductive speciation, inability of 2 groups to produce fertile offspring, happens mostly when the number of chromosomes changes. a donkey has more chromosomes than a horse so mules can't reproduce.it's pretty cool that neanderthals and denisovans could reproduce with humans though isnt it! like 60 000 parent to child cycles lataer and they can still procreate across that expanse of evolution.then again, tigers and lions diverged 3.7 million years ago, and ligers and tiglons can have fertile offspring, that's after 500 000 generations cos female lions and tigers have babies from 4 till 14 years so over 10 generations every century.gives an idea of the speed of genetic change.you would think that a sausage dog and a newfoundland were different species but they arent, and that's only a few hundred generations of changing their shapes.Edited by toine, : No reason given.

Buck Scientific is a proud supporter of spam!Edited by Admin, : Despam.

thank for dis all

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This message is a reply to:
	Message 15 by Loudmouth, posted 03-03-2005 2:32 PM		Loudmouth has not replied

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