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Re: Blood flow in Sauropods
> A 8 metre long neck, 3 metres above the ground allows you to cut a
>16 metre wide swathe through the vegetation at a height of 3 metres
>of less without overloading the blood circulation to the head
>associated with raising the neck above the horizontal ... That is a
>blinking good use for a long horizontal neck.
and Stan replied:
>>I have to disagree. *All* living animals with similar long necks
>>are *high* browsers. They normall browse at the vertical limit of
>>their reach. The similarity of sauropodomorph necks to those of
>>living giraffes, camels, llamas and such like is too close to be
>>mere coincidence. This is clear evidence that they were high
>>browsers. Even the less extreme neck of the gerenuk is apparently an
>>adaptation for high browsing.
>>The simple fact is that a long neck is a "maintenance" and
>>development problem and merely establishing a long reach is an
>>insufficient advantage to overcome these problems. [Even when
>>horizaontal such a long neck requires special muscles and tendons to
>>support it, and costs more energy to hold in place than a normal
>>neck].
Stan,
You are being species-biased towards mammals.
Geese, ostriches, emus, storks, herons, flamingos, and loons all have
long necks. Emus, flamingos, and ostriches even fit into the
proportion of length-of-neck-to-body-length similar to sauropods.
They are none of them high browsers. Not even the vegetarian-oriented
geese. They graze.
-Betty Cunningham
(bcunning@nssi.com at work)
(bettyc@flyinggoat.com in the studio)