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Re: Velociraptor profiles and a little background
> One of the first things a person learns when starting with dinosaurs is
> dinosaurs couldn't swim
_All_ dinosaurs couldn't swim? While almost all living vertebrates can?
> and now you are advocating that they could?
1. Sure. 2. I'm speaking of a certain small group of coelurosaurs.
> It hardly seems plausible, even if the
> feathers could make some lift in the water.
Why lift? With all these air sacs, the animal produces already more than
enough lift and has to care about how to stay down. Beating wings underwater
produces thrust. Lots of living birds do this.
> From the point that an animal starts with swimming, look at whales
> and manatees,
They aren't _starting_ to swim. They have become _exclusively aquatic_. Look
at otters. Oh, er, and penguins. :-)
> It could have helped with staying warm but do you see hairs on whales?
> No, [...] When you go into the water and when you are all
> hairy, it is a major disadvantage, because hairs slow you down.
You do know what otters do? You do know what _all birds I know of_ do, even
those that never come close to water except rain? They impregnate their body
coverings with oily secretions. (Galliformes have reduced that gland on the
tail, but they still have it.)
> And another thing, when you have feathers
> and you venture into the water, it's practicly suicide!
You tell this to any water bird. Are you making a strawman of yourself? :-)
> When feathers get wet, they become heavy, making it almost
> impossible to swim.
1. Usually they don't get wet. I've seen lots of feathers lying on water as
if the water were solid. Most diving birds stay completely dry.
2. Cormorant wings do get wet. This has an advantage -- it keeps the
cormorants down, counteracting the massive buoyancy. It is an adaptation.