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RE: not why the long face? but:why the long neck?



Hi David,

Increasing visual range (at least for terrestrial forms) is certainly
important for both predation (spotting prey) and defence (spotting potential
predators). Various terrestrial snakes also use an elevated 'alert' head
posture when moving or resting (there are some observations and discussion
in a couple of my papers at the tinyurl below).

Another thing is the use of inertial feeding (the classic paper on this was
by Carl Gans in 1960, I think in American Naturalist, I'm not sure if it's
easily available); the long neck (and snout) allows the tip of the snout to
be rapidly accelerated, useful both for battering prey to death, and
initiating swallowing by 'tossing' items down the throat (cf. herons,
kingfishers etc). Once the neck is long enough there's some capacity for an
actual predatory 'strike' as in snakes and some birds.

Then there's the use of the throat in respiration, both gular pumping of air
to the lungs (something goannas can do and other squamates generally can't,
allowing breathing while running), and gular fluttering for evaporative heat
loss. You should find useful references on this stuff at Eric Pianka's site.

I'd agree that these are all potential advantages of long necks in ancestors
of dinosaurs and pterosaurs, if that's what you're thinking. ;)

-----------------------------------------------
Dr John D. Scanlon, FCD
Riversleigh Fossil Centre, Outback at Isa
riversleigh@outbackatisa.com.au
http://tinyurl.com/f2rby
 
"Get this $%#@* python off me!", said Tom laocoonically.


-----Original Message-----
From: David Peters [mailto:davidrpeters@charter.net] 
Sent: 09 October, 2009 10:10 PM
To: dinosaur mailing list
Subject: Not: why the long face? but:why the long neck?

Curious for reasons as to what certain monitors do with their long,  
long neck?

Spying seems to be one reason. And if they're evasive, perhaps it  
gives a little extra time to spot and run?

David Peters
St. Louis