[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Blood flow in Sauropods



>From: pwillis@ozemail.com.au (Paul Willis)
 > 
 > 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.
 > 
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].

swf@elsegundoca.attgis.com              sarima@netcom.com

The peace of God be with you.