simian

<a href="http://story.news.yahoo.com/news?tmpl=story2&cid=570&ncid=753&e=1&u=/nm/20020913/sc_nm/science_penis_dc" target="_blank">Brief article</a> on the oldest known penis. I don't know who this will interest, but thougt it was worth passing along.

This is the oldest known penis, but does anybody know how far back the penis might go? Is is a structure that was common (like a leg) or something that evolved more than once (like eyes)?


Simian

MortalWombat

Depends on how cold the water is.

Abacus

I found this kind of interesting:

That's some mighty big sperm!

theyeti

Well, I thought Strom Thurmond had the oldest known penis, but in any case, the structure that would be called a "penis" in ostracods is not likely to be homologous to those of mammals. It may be that the genes which are responsible for the development of the structures are homolgous (like Hox genes which are responsible for limb development), but the structures themselves are likely not. Reptiles for example have hemipenises, which are different from the penises of mammals (though possibly related). Crusteacea and other invertebrates almost assuredly have non-related structures. Basically, all that's called for is a long tube of sorts that can place sperm in the proper location. In octopi, this function is taken up by a specialized arm of theirs (which just picks up the sperm and sticks it in the female). Other animals just release bunches of sperm into the environment and let them swim about until they find an egg. So I think the answer is that "penis" like structures, at least if you're talking about the end product of the developmental pathway, evolved more than once. The real question is, am I related to John Holmes, or is this an example of a paralellism?

theyeti

thebeave

Good to see that there is a penis out there that has been out of use even longer than mine.