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Re: sauropod feeding dogma*



Kenneth Carpenter writes;

>In addition, there is a false assumption that 
>trees of the Jurassic were so closely related to certain trees today 
>that they did not evolve much.

I'll grant that there may be some changes since the Jurassic, but I suggest that
the result was in *smaller* trees.  IMHO, the best defence against being fed
upon for any organism is to increase one's size, which seems to be a pattern in
evolution (look at the first amphibians, the different dinosaurian groups, and
the Cenozoic mammals).  Let's say that conifers and sauropods evolved at the
same time (a correct statement, if I remember my paleobotany correctly).  In
order to protect the top of the tree, where the primary growth meristem is
located, there may be an evolutionary pressure for an increase in the average
height of the species.  As the sauropods get larger (presumably as a defense
against the theropods), they will force some tree groups to get even larger.

Since the end of the Mesozoic, there hasn't been any animals big enough to feast
on the tall conifers, so a smaller varieties would have as good a chance at
survival as the bigger ones.

>As I wrote, the fossil evidence in the Morrison Formation does not 
>support the existance of many giant trees.

Yeah, there is no trunk evidence to directly support large conifers, but AFAIK
cones from sequoias have been found.  As a result, to conclude that sequoia
sized trees were present in the Jurassic is an easy deduction.  Besides, relying
on negative evidence to prove a point has been fatal to many past ideas.

Besides, what was _Seismosaurus_ feeding on?  It sure wasn't a ground feeder.
Otherwise, it would have that long neck at ground level, a welcome target for
any theropod.

Rob

***
Evolution = God's kingdom with a facelift.