Ring species as evidence for speciation

there are several nice little examples of the same species that lives on either side of a something and when reconnected no longer interact like the same species. for instance, there is a crab that lives both east and west of central america in the respective waters. when they built the panama canal these two east and west crabs were reintroduced... instead of mating, they fought. and of course, the very first principle of speciation is a failure to interbreed. even if it is by 'choice' because they simply don't recognize each other.

yes i know. and horses and zebras can be interbred (if i'm not mistaken) not to mention that extinct species of zebra.there are many more factors to speciation. but failure to breed is one of them. also, there are many more reasons why things can't interbreed than simple genetics. like the mixed signals i mentioned and a few other things.it's simply not as simple a process as people think.This message has been edited by brennakimi, 06-28-2004 06:41 PM

only with donkeys... and only one way (ie if you have a male horse and a female donkey versus the other way. one is fertile, the other isn't). as far as i know. cause they are trying to use horses to bring back an extinct zebra species. but i could be mistaken.

hm. interesting.