Galapagos finches

No, Tamara, I think the size difference is enough to discourage that. I don't know if the experiment has ever been done but I would be surprised if they managed to have sex. Then the problem of viability of a Bernard pup in a chihuahua mother would arise.

But the biological definition of species involves the behavior in nature. That is, even animals that could successfully breed may not for behavioral or other reasons. If they don't (or don't very often the definition makes them different species.Are tigers and lions now the same species? They can breed and, I think, produce fertile offspring. However, they tend not to as they don't usually recognize each other as mates. (Of course, they rarely see each other for that matter.)Would nature make adjustments? I don't know. Do we have a dog breeder present?

You offer up very few facts in amongst your assertions. It would be nice if you got them right when you did. - is wrong (if you mean breed wolves with dogs). So what is your definition of 'species' to replace the rather complex defintions given at the referenced site?http://www.wordiq.com/cgi-bin/knowledge/lookup.cgi?title=...

There are a couple of points being bounced around here.1) What is a species?2) Has speciation taken place amoung finchs of the Galopagos?1) Since speciation is a gradual process in many cases it can be difficult to decide then the line has been crossed. Until there is a reproductive barrier speciation may not be clear. However, for any number of reasons (historical, convenience, genetic) a species may be declared. It is the classic lumper and spliter argument.2) Given that speciation may start and not complete it is possible, as you sources note, that it could reverse. It seems that the experts who are argueing over this have somewhat fewer species than once upon a time but still more than one.I don't see why this is such a large issue. Cases like this aren't too surprising and there are lots of cases here a reproductive barrier does occur and full speciation takes place.For now we have a number of finch species. Only by settling on a defintion and applying that to the populations there with enough data gathered are we going to be satified that we have the 'right' number and be able to know if the number if changing up or down.(from a previous post) Yes it does. The first case of this I heard of I learned about here. There are such a series of gulls around the north pole.

I've heard that line before.Science works from a current best consensus. It does change with time. However, to say that new data will overturn things is hardly an arguement with any weight is it?I can decide that new data will support what I want to be true too. Real researchers go out to find the new data if they want to support their position.Aside from all that what is the big deal about the darned finches?

Of course. But it just doesn't cover everything. It is also, on it's own, fuzzy.It comes down to everything about the individual is a bit unclear (and amazingly even that isn't cut and dried). The species is then next grouping of living things. It has a lot of clarity and crisp edges most of the time but not all of the time.Again, why does it matter if there are lots of finch species or one? It doesn't seem to make any difference to anything to me.

This reminds me of something else, (again no reference) where populations are separated by some kind of parasite. The article discussed this as a means to very rapid speciationI remember no details.