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Horns, fatalities, Growth Rates



Lawrence Dunn wrote:

> I heard Horner speak at the AMNH a few years ago, and he said,
> first, that Triceratops did not use its horns for defense, because
> "you don't go around sticking your face into things;" he then went
> on to say, as Jeff indicates, that Tyrannosaurs were not hunters
> because they would have been gored by Triceratops.  Can anyone who
> knows Horner unravel this logic for me?  I must have misunderstood.

I read a study somewhere showing that dehorned female rhinos 
(a conservation measure) suffered nearly 100% infant mortality due to their 
inability to defend their young from predators. And consider that those 
predators are, maximum, lion-sized, and I think you have a good demo of how 
useful it can be to be able to stick your face with a spike into something 
threatening.

Growth rates: there was some discussion on dino growth rates recently...I saw
an interesting programme last night about kestrels (a small hawk here in
Europe), where a clutch of 4 eggs hatched over a period of about a week, so
that by the time the youngest chick hatched, the oldest was about twice as
big. The interesting point is that the mother preferentially fed this chick
at up to 300% more than the other three in the brood, so that by the time
they were all ready to fly they were all the same size. This seems to
demonstrate (to me, in my ignorance) that growth rate in, at least, kestrel
chicks, can be "accelerated" to a defined "goal". Maybe this could be
applicable to dino growth in some way?

martin