Alright all you biological scientists out there

[Serpentine]

I remember, years ago, reading about some birds, in the arctic or somewhere in the north, I think, whose range kept extending around the lake, with little changes each time, until they finally came full-circle and the new birds couldn't breed with - and therefore were a different species to - the old ones, even though there was a continuous line all the way back. This would be a perfect example of parapatric speciation for an assignment I'm doing, but I can't remember what the birds were or where they were or anything. Anyone else heard of this, or anything like it?

[T'ze'hai]

You made the deep inside of my brains itch, because i know what you mean, but I can't think of the right species right now :smallconfused: .
Anyway, I did find this: http://www.orientalia.org/wisdom/Philosophy/Species.shtml

Maybe to get started?

See if I can dig up my studies books and find the answer...

[Serpentine]

Well, I figured out that I'm trying to find ring species. Now to work out whether they're an example of parapatric speciation or not... :smallsigh:

edit: Wikipedia says yes. Hurrah! Problem solved!

[Skippy]

I was about to quote Monty Python, you know... About the swallows and the coconuts...

[Pyro]

Hah. My science teacher showed us a video almost exactly like the OP last year. Pretty much talked about how its hard to distinguish between species because one Group A can breed with group B, but not with Group C, and Group B and breed with both. Its a pity I can't remember the name of the species.