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Ben L. wrote:
<I'm only an amateur, but here are my thoughts:>
So am I, but that doesn't stop me!
<Perhaps small pterosaurs and birds/protobirds flew around sauropods
and snatched flys and other annoying insects, and removed dead
skin/scabs as well.>
Ah, yes. Oxpecker pterosaurs.
<As for the sauropod drinking problem, who knows. The dip-and-sip
chicken style may well be a literal pain in the neck, and the
immersing-head-in-water style would have to involve a lot of pumping
action to get the water back up to the gut.>
For the diplodocids, the siphon-snout method would be very ideal.
First, the neck was held neutrally more or less level to the ground,
so in *Diplodocus*, the head was only as high as the shoulder joint
(higher or lower if it wanted) and that's not high, not far to reach
down, and not for to bend up. Regards to pressure when swallowing are
reduced, because the water (and this applies to food, too) is
travelling more or less level, greater pressure like airsac
enlargements in the neck force the water along at lot less demands
than if the head was held some twenty to thirty feet in the air on a
more or less vertical neck.
Second, the nares are located back on the skull, and this could mean
that the position of the epiglottis (the throat-valve) may have been
higher up than in mammals, as in birds, who can drink and breathe at
the same time because air and food move without interfering with each
other, unlike in mammals, who have to pause. Hence, a bird won't choke
or asphyxiate to death swallowing something like a fish or
regurgitated food, still breathing.
Camarasaurids had very short necks, and so were not as subject to
the pressure-problems of diplodocids, but still manage to have
incredibly large areas for airsacs.
So the method would go someway like this.
1. take your fill
2. lift neck to fifteen degrees off the horizontal
4. drop head to water
5. repeat as neccessary
It's parsimonious, requires no leaps of faith, has fossil evidence
to back it up, and physics cannot disprove it, even if the atmospheric
pressure were lesser or greater than it is now (not a thread I want to
get into, if I'm not already).
<What about the old trunk-on-a-sauropod theory? If there is evidence
for trunks, then it would be allow the animal to drink without
completely lowering the neck or moving it excessively. Or, maybe they
adapted to not requiring too much water, and recived it via plants or
As I understand it, the trunk theory best fits the feeder
adaptations area, while drinking is best explainable through other
means. Elephants, AFAIK, use trunks, though they are agile and able to
bend down to drink, to feed or drink while maintaining a pose of
alertness, should lions or tigers come by. Those that wallow do so in
great numbers. _E pluribus unum_.
Jaime A. Headden
Qilong, the website, at:
All comments and criticisms are welcome!
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