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Re: Dinosaur Heresies

>COUNTER-ARGUMENT: 3,000 lizard species and 2,700 snake species
>today vs 3,000 non-flying mammals.

I agree with a lot of Bakker's ideas, but is a species count really indicative
of how successful a class is? It seems to me that you could have 10 very rare
insignificant species of one class totally dominated by 1 species of another
class. IMHO what you really need to do is count the number of individuals of
each class in a given area of the specified environment.

>ORTHODOX: Enormous brontosaurs had to live in water.

It has been proposed that the water pressure around the ribs of a diplodocid
standing in water up to its neck would be so great that it could not expand
its lungs against the pressure in order to breathe.

>not swamps. Centrosaurus teeth in the camarasaur demonstrates

I presume this is a typo. Isn't Centrosaurus a ceratopsian? Maybe you meant

>COUNTER-ARGUMENT: Smooth rounded pebbles have been found through
>and around rib fossils which could have been gizzard stones for
>grinding large volumes of tough food as confirmed by the teeth.
>Horizontal head and vertical neck in Diplodocus imply that its
>neck was held nearly vertically during feeding at twenty to
>thirty feet above the ground.

Microscopic analysis of the dirt where the stomach of diplodocids would be has
shown that the stomach contents was mainly pine needles.

>ORTHODOX: The two great dinosaur clans, the beaked dinosaurs
>and the meat-eaters, evolved from quite different ancestors
>(brontosaurs supposedly evolved from early meat-eaters).

This has always presented a problem to me. I find it difficult to visualize how
a species can change from herbivore to carnivore, or vice-versa. Try to imagine
an Apatosaurus munching on pine needles, and then suddenly deciding that he
wants a Compsognathus for dessert. Or try to imagine a Tyrannosaurus having a
fern salad for lunch. Not.

>ORTHODOX: The dinosaurs died out because of a catastrophic
>event such a large meteor.

It's funny how just a decade or so ago this was the unorthodox view. It was
thought at that time that dinosaurs were killed by diseases, or by mammals
eating their eggs, and other silly ideas that are now coming back again. This
is the one point in Bakker's book where I strongly disagree with him. It seems
to me too much to swallow that it is just an incredible coincidence that a
giant meteor or comet just happened to strike the Earth at exactly the end of
the dinosaur age and deposit ash all over the world, but that it had nothing to
do with the mass extinction. The ideas of disease, changing climate, etc. don't
work because all these things were happening all through the 200my of the
dinosaur age, but they survived that long. Also, the other ideas don't explain
the extinction of sea reptiles that occurred at the same time.

>Armor-plated nodosaurs have been found lying on their backs
>embedded in the now hardened deposits left by the mud on the
>sea floor at Como, Wyoming and Kansas. How did this occur?

Perhaps they were washed out to sea in a flood?

>The most common, large plant-eaters of the Late Cretaceous
>were the duckbills without any sort of obvious defense. How
>did the duckbills escape their enemies?

Many of todays large herds of herbivores have no obvious defense. They survive
by reproducing fast enough to replace their losses to predators.

>No fossils have been discovered to show how the pterodactyl's
>forelimbs became transformed into wings.

Gradually :)

>FAMILY TREE (lower case is a family)

It's difficult for an amateur to judge the validity of all the different family
trees proposed since the authors of most popular books never explain on what
characteristics these groups are differentiated.

>"I use BRONTOSAURUS not APATOSAURUS even though, according to the
>International Code of Zoological Nomenclature, the latter is the
>legal name. Al Romer used to complain that "rules of nomenclature
>should server the cause of science, not the other way around."

Yes! I agree very strongly. The name change only served to confuse people. The
name Brontosaurus had been used in hundreds of popular books for decades. No-one
had every heard of Apatosaurus at that time. So, which name does it make more
SENSE to go with?

I want to re-iterate that I agree with almost all of Bakkers ideas. Dinosaurs
couldn't possibly have been as successful as they were (suppressing mammals et
al for hundreds of millions of years) if they were slow, stupid, cold-blooded,