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I don't think three birds with different uses of a wing is homology????? Experts please!--[[User:Random Replicator|Random Replicator]] ([[User talk:Random Replicator|talk]]) 01:21, 27 January 2008 (UTC)
::On self-reflection I was thinking more on the lines of bat, human arm and whale flipper --- but they are all mammals so what is wrong with using all birds? Yes --- excellent Jim ---jolly good! --[[User:Random Replicator|Random Replicator]] ([[User talk:Random Replicator|talk]]) 18:15, 27 January 2008 (UTC)
:::"More specifically, in evolutionary biology, homology has come to mean any similarity between characters that is due to their shared ancestry." Birds' wings are not similar characters, they are the same character. But, of course they're also similar characters and homologous because they have a shared common ancestry, that's why we call them birds, and why we call their forelimbs wings, because they are all birds, but it doesn't show the reader of the article anything to say that the eyes of all apes are homologous, the flippers of all whales are homologous, the tails of all fish are homologous, or the wings of all birds are homologous. What shows homology is to look at characters that we, as humans looking at characteristics of animals, don't already call all the same thing, to show their shared ancestry. The forelimbs of vertebrates is the classic example, the wings of birds and the fore limbs of whales and the human arm are all homologous. We don't necessarily think of them as homologous and of the shared common ancestry of these vertebrates if we're not used to thinking of evolution-and this article is about thinking about evolution. That the wings of birds are all derived from the birds having a shared common ancestry does not have any power in it. Birds' wings are not called different things, they're called wings. But a human forelimb is commonly called an arm, and bird's forelimb is commonly called a wing, and even a bat's forelimb is called a wing, but is a very different animal from a bird's forelimb.
:::To introduce the concept that things that are different may have a shared common ancestry by giving things that are all the same as an example is pointless. Birds' wings show the great diversity of characters within a group. --[[User:Amaltheus|Amaltheus]] ([[User talk:Amaltheus|talk]]) 20:54, 27 January 2008 (UTC)
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