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RE: Cooperative Behavior



A lot of recent field studies dispute that lions actually do the "flush to 
waiting pride members".  As an example, the studies by C. Packer, 1986 
American Naturalist, and several more recent works by Packer and Creel. 
  Even the classic study by Schaller (in the book the Serengeti Lion, 1972) 
is not firm on this point.

Examples that appear to show the careful coordination do appear - and can 
be seen on Discovery channel shows etc.  However it is difficult to show 
that it is truly planned versus spontaneous.  Perhaps the pride members 
that appear to be waiting are just stalking the same animal and lunge when 
the prey happens to come in their direction.

Careful analysis of field data shows that many times that is exactly what 
happens.   Various pride members will accidentally spook the prey 
prematurely, or it will not run in the direction of the waiting pack 
members.   A statistical analysis of the wind direction shows that the 
famous "stalk from downwind so you are not detected" is simply wrong - 
there is no statistical correlation to wind direction.   Human observers 
can read into this behavior more than is actually there.

Consider that the flocking movements of birds or schooling of fish is NOT 
planned behavior.  It occurs when each individual follows a simple rule. 
 With N individuals following the same rules, it can appear coordinated, 
when in fact there is no explicit plan, and no explicit communication.

Ants are the best examples.  They have highly organized foraging behavior, 
especially in army ants, leaf cutter ants etc.   However it is all the 
example of collective effect of simple local rules.  Dinosaurs may not be 
brainy, but they were at least as smart as ants!

Canids do seem to cooperate more, but even there it is not clear that the 
group behavior isn't really a variation of this individual rules rather 
than planned or communicated cooperation.

In any event, it certainly seems possible that dinosaurs could have lived 
in groups and "cooperated" in the sense that they would mob prey and share. 
  Komodo monitors do this, many birds do it etc.

Nathan

----------
From:  Michael [SMTP:tons@ccs.netside.com]
Sent:  Monday, February 24, 1997 5:34 AM
To:  Nathan Myhrvold; dinosaur@usc.edu
Subject:  RE: Cooperative Behavior

Lions do exhibit cooperative behavior as well as wild dogs and wolves
among others(there are more).  This is not we see you, the fastest
catch it, someone kills it.  It requires at least higher learning if
not abstraction.  Lions flush prey into waiting pride members who are
hiding in tall grass, not standing around or chasing prey themselves.
The list is longer, but this serves as a good example.

I don't have any idea if dinosaurs did this.  It can be learned and
taught, but I have doubts if dinosaurs could.  They certainly can
hunt like cheetahs do.  They will chase an animal, one catches it,
and someone kills it.  Cheetahs share well.  In fact if there are
more that two, one will often be a lookout while the others eat.

Michael Teuton
803-732-2327 Phone
803-749-6191 Fax