julianm

There is an interesting, if a bit too lengthy, article in the New York Times about de-extinction. What do you think about it? I feel that the idea involves a lot of hard work that carries some risks and costs, and it is also mis-sold - the cloned creatures will not be the same thing as the extinct ones. But there seems to be a passionate group of advocates, and if they are keen to work on such a projects, then why not?

Thank you for all replies - extremely interesting! So in short, speciation can occur whenever a factor creates a population subgroup. That factor can be geography (as in ring species), mating preferences (Charon's butterflies) or time, all leading to a sort of reproductive isolation.

This is a fascinating question. As chadn737 wrote colonisation will occur by a small group of people. Those might be picked by a government agency and match military requirements, be intelligent, athletic, of certain psychological profile(s) and screened for genetic diseases. The colonists may be children of NASA's astronaut selection process that one day could lead to a distinct group... homo astronautis? The oldest anatomically modern human fossils date back ~190,000 years ago.... Still, Neanderthals were probably older than 200,000 years anyway, so they might still be winning the longevity race. And Homo heidelbergensis are ahead still of both.

Thank you all for your answers, very informative! chadn737, as for the definition of species, is it not the ability to interbreed that is the key to differentiating between species? If not, then my question is misleading indeed. If yes, then maybe speciation arises over a bumpy period of decreasing compatibility, with a series of less fertile offspring along the way… Charon, I get the idea of reproductive isolation. Is that a necessary requirement for all new species? EDIT: the Kronforst study you mention answers this question. With a "no". I wonder if I can look at this differently - it is not that new distinct species arise, it is that all intermediary individuals (hybrids, those in the "gap") simply die out or are not numerous enough.

There is a question about evolution that has been bugging me for a while, and I will be very grateful if someone can help with an explanation. I suppose we define new species as distinct ones that cannot mate with their ancestor species. But if it was random mutation that created a new species, surely it needed to occur at the same time in a breeding pair. If it occurred in only one animal, then the mutation wouldn’t be able to procreate and start that new species. But mutations occurring in a couple (or more individuals) simultaneously seem very very unlikely. What am I getting wrong?