Originally Posted by tore

This is because the duck's penis has a different origin from our own. By that, I mean that with dogs, we have a common ancestor who had a penis and it evolved a little differently in the line that would become dogs than it did in the line that would give rise to humans .. But the penis of the duck is something completely different.

Birds only have one hole down there, the cloaca, where everything happens. **** comes out of it, eggs come out of it and sperm has to come in/out of it. Most male birds are able to portrude their cloacas so that they can penetrate the females with it while geese and duck males have evolved this penis that they use. I guess it's evolutionary origin is the cloaca, so it's a portrution evolved from the intestinal wall near the hole or something like that.

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