the liver and the brain

dan michaels feedbackdroids at yahoo.com
Sat Sep 4 22:53:45 EST 2004

r norman <rsn_ at _comcast.net> wrote in message news:<is5kj05apke4p3fhld15opsvt328tfkuag at 4ax.com>...
> On Sat, 04 Sep 2004 18:20:33 GMT, lesterDELzick at worldnet.att.net
> (Lester Zick) wrote:
> >On 4 Sep 2004 09:35:30 -0700, feedbackdroids at yahoo.com (dan michaels)
> >in comp.ai.philosophy wrote:
> <snip>
> >> ...  my question regards the level of development of
> >>perceptual systems at the time of birth in precocial ungulates ...
> >>
> >>It's a fairly interesting problem in its own right, since a baby zebra
> >>has to be ready to flee from a lion shortly after birth, if it ever
> >>wants to get to be an adult zebra. To flee from a lion, it might help
> >>to be able to distinquish one from a parent zebra, so upon seeing its
> >>own parent, it doesn't go running off into the jaws of the nearest
> >>lion. I guess it's conceivable the adult zebra would be able to
> >>"teach" its baby what a lion is in the first hour or so, or that the
> >>baby learns on its own the first time a lion comes to eat it. Operant
> >>conditioning rules, so long as the organism makes it through the first
> >>day against something 10X its size and power, not to mention the big
> >>teeth.
> >
> >The baby zebra wouldn't have to learn to discriminate lions. It would
> >just have to learn to stay with its mother, a much easier task for
> >which it is presumably born pretty much ready.
> >
> >Regards - Lester
> You are right in questioning the specific behavioral capabilities
> needed for a newborn to survive.  Still, putting aside the particular
> focus on ungulates and on recognition of predators as a specific
> animals and behaviors there are still very interesting scientific
> questions behind all this.  Exactly what are the differences in brain
> development and function between precocial and altricial animals?  To
> what extent does a reliance on learning vs. instinct play a role in
> the behavioral repertoire of precocial vs.altricial animals?  
> I would only just repeat here something I have been trying to say for
> some time now.  These differences are well known and well recognized
> as reproductive strategies with important implications for ecology,
> evolution, ethology, and development. There is a rather extensive
> literature about these, although not specifically about the ability of
> ungulates to recognize predators.

Yes, yes, to hell with ungulates. If you look at the *most* precocial
birds on patty's found list, can you postulate the hypothetical
balance between genetic hardcoding and post-natal development/learning
regards their visual systems? I see ducks are near the top of the
precocial list. Do they really "imprint" on their parents?


Precocial 1 Yes Yes Yes Yes Yes Megapodes 
Precocial 2 Yes Yes Yes Yes* No Ducks, Plovers 
Precocial 3 Yes Yes Yes Yes No Quail, Turkey 
Precocial 4 Yes Yes Yes Yes/No No Grebes, Rails 
Semi-precocial Yes Yes Yes/No No No Gulls, Terns 
Semi-altricial 1 Yes Yes No No No Herons, Hawks 
Semi-altricial 2 Yes No No No No Owls 
Altricial No No No No No Passerines 

More information about the Neur-sci mailing list

Send comments to us at biosci-help [At] net.bio.net