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Re: Triassic protofeathers and fake-heads
Rob wrote:
What would you say to the presence of armour in late Triassic
ornithischians then, if they were indeed found...
Peace,
Rob
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Rob, it would not surprised me if some late Triassic ornithischians had
some armor. I'm just saying that they would generally have less armor than
their Cretaceous descendants. We see a similar sort of arms race with
trilobites in the Paleozoic. You don't find the most spiny trilobites in
the Cambrian----they came later as the Paleozoic arms race escalated. I
would expect something similar among non-theropod dinosaurs during the
Mesozoic. And in the Cenozoic, armadillos armour didn't just suddenly
appear. It gradually improved as its predators got bigger and smarter.
Jaime said that my hypothesis was "ecologically" unsound because
predator on predator on attacks are rare. But I wasn't talking about
predators on predators. I was talking about early theropods attacking early
ornithischians and sauropodomorphs.
David's objections didn't make sense to me either. It's the predators
that are doing most of the brain development. Gazelles concentrate on speed
to escape, and their predators must compensate by a combination of some
speed increase, but mostly on agility and the brainpower to harness that
agility as the prey got faster and more agile.
There was a Mesozoic arms race just as surely as their was a Cenozoic
arms race. And more and more tetrapods had bigger and more complicated
brains than their Paleozoic ancestors. Sure brains are metabolically
expensive, but the advantages must outweigh the costs, or we would all still
have simple amphibian brains. Even if the mean hadn't gone up (and that is
arguable), the upper end brains have clearly been increasing in size and
mental ability.
The biggest doesn't necessarily have to be the smartest brain, but I
certainly couldn't be communicating with you all if I had the brain of a
therapsid, much less the brain of a Devonian amphibian. There are clearly
general trends from Paleozoic to Mesozoic to Cenozoic that are so obvious,
it puzzles me why people would want to argue against it. Is the word
"progress" so politically incorrect that we have to ignore the obvious
trends. This just seems like an overreaction to past mistakes, and the
pendulum gets swung too far the other way. A Komodo dragon may be dumb
compared to its mammalian or avian prey. But I bet it takes more brain
power for them to ambush their prey than for a frog to stick out its tongue
and catch an insect.
--------- Ken
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