ICANT writes:
But on Cocos Island there is and has been only one species they did not spectate in the same amount of time. Why is that?
Except that the Cocos Island finch is not a true finch. It belongs to the family Thraupidae while true finches belong to the family called Fringillidae. It is in fact a tanager. You are also making the assumption that it has lived on Cocos island for as long as the finches on Galapagos, when for all you know it may be a relatively recent arrival to Cocos (recent being measured in mere centuries). It is closely related to other tanagers on the mainland.
Tanagers do tend to form groups of endemic species, according to wikipedia. I'll leave it to any bird experts to explain why.
Respectfully,
-Meldinoor
ABE: It looks like Darwin's finches have also been reclassified as tanagers, putting them in the same family as the Cocos Island Finch.
Edited by Meldinoor, : No reason given.