Re: Sex

["Gavin Rymill" <gavin@gavinrymill.com>]

> Crabs as an analogy for dinosaurs is an interesting idea... apart from
that
> really no known amniote uses external fertilization (apart from humans, in
> vitro),

Conversely - There are no known amniotes which, as adults, have huge great
plates and metre-long spikes!!! Doesn't prove the dinos didn't have them!!
:o)

Also, I'm interested in the in vitro idea for Stegs... do we really know
just how advanced they were...?

> I doubt sperm cells could get through eggshell, amnion, and what
> else there is in an amniote egg.

Yep, you're absolutely right. We'll call the external fertilization
hypothesis rejected.

So we're back to finding sexual positions that worked...

> Kenneth Carpenter, in his book "Eggs, Nests, and Baby Dinosaurs" IIRC, has
> even portrayed a pair of *Stegosaurus*... erm... accomplishing vertical
gene
> transfer :-P

I did a quick sketch....
*parental advisory* The following drawing may not be suitable for younger
palaeontologists or those who are easily offended. :o))
 http://gavinrymill.com/dinosaurs/SteggySex2.gif

And an even more hasty sketch of the sideways position here.
http://gavinrymill.com/dinosaurs/SteggySex3.gif  Personally I can't see this
happening. I don't think the animal on the ground is going to be very happy.
Its plates are in danger of being rolled on - ouch! I just can't see a 5+
tonne animal dropping heavily onto its side, being sat on by another 5+
tonne animal and then happily springing back onto its feet.

When I showed the second image to one of my friends he asked, "Is the bottom
one dead??"
And, after a moments consideration, I answered, "After attempting that...
Probably."

Gav
www.gavinrymill.com        ICQ: 33916140  /  AOLIM: ExtinctGav