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

Re: Re: Raptor Intelligence

jimf@strauss.psych.upenn.edu (Jim Foley) wrote:
> From: th81 <Thomas_R_HOLTZ@umail.umd.edu>
>  > 
>  > 
>  > I really like Dale, and he has supported my work, but I REALLY dislike the
>  > 'roid.  Not as an excerise, but because it wound up looking so humanoid.
>  > Troodontids already had a bipedal gait and manipulative hands, and given
>  > that many dinosaurs had heavy skulls but retained a horizontal spine, I do
>  > not think the totally erect posture is justified.
> Add my vote of disapproval to the dinosauroid; it ended up looking way
> too much like a human in a lizard skin.

Well, discussions are more fun if there is the clash of competing opinions:
How about this:

Dr. Russell must have had some rationale behind his speculation on
intelligent dinosauroids.  After all, ANYBODY can put a lizard skin
on a human frame (I like the `Gorn' (Gornt?) from the old Star Trek show :-)
But this one was presented as if it were supposed to be a plausible product
of evolution.

Now, humans are the odd shape we are, because of the need to overcome
limitations imposed by previous adaptations: ground-dwelling or brachiating
proto-apes didn't need their monkey tails, the articulations of our shoulders
derive from the apparatus for tree-climbing, our facility for aiming
projectiles and predicting trajectories may stem from our previous lifestyle
as arboreal monkeys jumping from tree limb to tree limb, etc.

We developed (what we call) high intelligence in order to compensate for and
exceed our in-built limitations for the purposes of edible-plant recognition,
scavenging, predator avoidance and/or hunting, as we expanded into new
ecological niches already dominated by other, lower-intelligence animals.

Now, what would a troodontoid need intelligence for, if it still had a
generalized carnivore body type?  The characteristics of sharp teeth and
claws, fast running and long-tailed agility would be easy to enhance
evolutionarily if this hypothetical pre-intelligent 'sauroid were to adopt
an (even) more conventional carnivorous/hunting lifestyle.  Much easier
to select for increasingly larger claws than for the ability to make tools.
Since it already was smarter than its prey or other competition, there
wouldn't be as much selective advantage to becoming incrementally smarter,
as to just being a more effective stalker/runner/killer, if evolution
still had a typical dino body type as raw material to work with.  Therefore,
in order for intelligence enhancement to be the preferred or easiest direction
for evolution to occur, something must have precluded other attributes
from being adapted.  (like, perhaps, tails were lost in an arboreal epoch
in their history, or, blunt teeth were evolved during a period of herbivory).

To cause evolution to produce an enhanced brain, the accidents of history
would have had to make the pre-sauroids' bodies maladaptive for the niche
they found themselves in.  Either the environment changed so they couldn't
continue the lifestyle to which they had become accustomed, or a new niche
opened up that they were pre-adapted to exploit, if only they could become
more intelligent.

What I'm saying is that: just as humans do not look much like a typical
mammal, we should EXPECT an intelligent troodontoid to have a morphology
VERY MUCH different from a typical theropod.  It would be interesting to
find out if there were a rationale for how Russell's dinosauroid was to
have evolved.

  Mike Bonham        bonham@jade.ab.ca      Jade Simulations International
``Perfection is achieved, not when there is no longer anything to add, but
when there is no longer anything to take away.'' (but you should see my .sig!)