Re: rearing sauropods

["no go" <honkietong@hotmail.com>]

> I certainly agree that there seems to be a lack of proof that a olng neck
> feeding horizpntally is a good thing in the evolutionary sense. There has
> been sort of an aceptance of the idea that this is a good thing but I fail
> to see that that is the case. There is no counterpart today of that 
> bauplan.
> If there is a treeless plain what is the benefit? the animal could simply
> walk over to any new spot. Having a long neck lime the sauropods have is an
> expensive characteristic. If there are a few trees, there is the same
> comment, just walk over to feed at a new spot. If there is a forest, I 
> would
> think it really gets to be an iffy thing. Think about snaking ones neck
> through the trees to get to a feeding point. If aroused one would probably
> just break ones neck to get out of that position. Where is the advantage?
> The advantage in all cases seems to be more likely in a vertical direction.
>
> paul


Thanks, but I'm not entirely clear on the possible neck articulation of the 
sauropods themselves. And prehaps we should observe before we calculate. If 
we can determine that the sauropods had necks that were more flexible in 
either way (it seems that opinions differ among the experts on this), we can 
determine the behaviour of the animal with far less confusion. An animal 
with a significant horizontal articulation would be good as a horziontal 
browser, or vice versa, irregardless of all our misgivings about the 
possible pitfalls of its behaviour (ie: breaking neck amongst trees or 
losing blood pressure in the head).

However, no matter the feeding behaviour, a long neck is going to be, well, 
a pain in the neck. There are a great deal of problems associated with 
having a long neck. Be it getting blood all the way to the head, making sure 
the entire structure is rigid, and so on and so forth. All these adaptations 
indicate the sauropods must have had some form of selective pressure on them 
which favoured them to adopt such extensive features.

On the other hand, the lack of modern counterparts is hardly the reason to 
reject such an idea in the first place. Though it admittedly means there has 
to be a good reason to believe in such an idea. Prehaps the idea of a 
low-necked sauropod might be possible because they avoided the trees 
altogether and stuck the the plains (were there any in the Jurassic large 
enough to support such a number of massive horziontal feeders?). Also, 
wouldn't it be easier to evolve longer legs t help you in the quest for 
upper foliage if you are planning on a vertical necked plan? Longer legs 
saves you some trouble associated with a massively long neck and it seems to 
me sauropods almost-sure vertical feeders like Brachiosaurus are good 
examples of this. The legs of the really long necks like Diplodcus seem 
suspiciously short to me, if their goal was only to reach up.

But personally, I do feel that energy savings in the horziontal feeding 
methods are illusionary. At their massive sizes, sauropods are incredibly 
efficent at energy conservation, and I doubt there's any significant energy 
savings in vacumming up vegation enough to consider it a reason for the 
long-neck (you'll need one heck of a long horziontal neck to make a 
difference). However, having a low, slung out neck would have acted as a 
wonderful counterbalance for their long tails, and prehaps evolved as a 
means of defense, rather then feeding. If only we knew the issue of sauropod 
neck articulation limits once and for all, our questions would have been 
solved.

PS: Why the predators didn't bother attacking from the front instead of the 
rear, when the tail was so deadly, is lost on me. Prehaps a sauropod 
approaching you at 4kph is much more threatening then it looks...


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