[sci.bio] reproductive stragegy and human behavior

gordonl@microsoft.UUCP (Gordon Letwin) (03/11/89)

In article <7337@rosevax.Rosemount.COM>, carole@rosevax.Rosemount.COM (Carole Ashmore) writes:
> 
> Oh goodness.  The trouble with 'The Argument from the Baboons' as my
> college anthro professor used to call it is that you can 'prove'
> anything about evolutionary trends by citing only the species that
> demonstrate the traits you want to prove are important  --just as
> certain religious people can 'prove' anything by quoting selectively
> enough from the Bible.  
> 
> The way to deal with this type of religious person is to know more about 
> the Bible than they do, so you can laugh in their face when they quote 
> Leviticus against homosexuality while eating lobster. And the way to 
> deal with sociobiologists is to know more about biology than they do.  
> Fortunately, neither is very difficult.

You seem to be stating here, indirectly, that you think sociobiology
is a bogus approach, and that all sociobiologists are wrong.   (Your
phrase "deal with...", in direct association with religious fundimentalists)
Is that indeed your stance, not that you disagree with a particular
claim, but that the entire approach is bogus?  If so, your beliefs in this
matter are easily shown to be incorrect.  Even Newsweek, this issue, 
will do the job.

	Pls advise

	gordon letwin

gordonl@microsoft.UUCP (Gordon Letwin) (03/11/89)

In article <7337@rosevax.Rosemount.COM>, carole@rosevax.Rosemount.COM (Carole Ashmore) writes:
> 
> Oh goodness.  The trouble with 'The Argument from the Baboons' as my
> college anthro professor used to call it is that you can 'prove'
> anything about evolutionary trends by citing only the species that
> demonstrate the traits you want to prove are important  --just as
> certain religious people can 'prove' anything by quoting selectively
> enough from the Bible.  

This is true enough.  The idea is to look at the balance of evidence.
If there isn't a uniform distribution of behavior, then thats an important
fact that is giving you info.


> Let's see now.  Most ungulates fall on the 'fast reproductive rate'
> side; most of them are prey, not predetors, and must keep their
> numbers up to keep the species up and the predetors in dinners.

Everybody must keep their numbers up.  Everybody keeps their numbers
up as high as possible.  Most ungulates have a SLOW reproductive
rate,  in the context of this discussion.  One a year.  Even three
a year.  A fast reproductive rate is 3 litters of 10 a year, or
10 million eggs a year.

> Ungulates that are not prey don't tend to keep harems, or even, for
> that matter to keep males as part of the herd; look at
> elephants.  

Yes, lets LOOK at elephants.  Isn't this the "fallacy of the baboons"?
You've ridiculed the use of examples to establish points, allowing
only counter examples.  Well, since I didn't state that ALL ungulates
keep harems, your mention of elephants is not a counter example, and
is therefore a fallacy, by your own reasoning.

Also, add to my arguments males that keep territorys.  THis isn't
the same thing as a harem, but its very similar - it provides
exclusive access to females.  Males in a great many specicies
keep territorys and fight off other males, esp. at breeding season.
Females may keep territories too, because they also have a food
role, but females don't repel other females in their territorys
during breeding activities.

Yours towards goose/gander sauce parity

	gordon

carole@rosevax.Rosemount.COM (Carole Ashmore) (03/15/89)

In article <845@microsoft.UUCP>, gordonl@microsoft.UUCP (Gordon Letwin) writes:
> In article <7337@rosevax.Rosemount.COM>, carole@rosevax.Rosemount.COM (Carole Ashmore) writes:
> > Let's see now.  Most ungulates fall on the 'fast reproductive rate'
> > side; most of them are prey, not predators, and must keep their
> > numbers up to keep the species up and the pradetors in dinners.
> 
> Everybody must keep their numbers up.  Everybody keeps their numbers
> up as high as possible.  


Gordon, this is simply not true.  Most predator species have built
into their instincts some type of behavior that serves to keep their
numbers *down*.  It is very unusual for a predator to reproduce to the
limit of the food supply.  In lions the adults eat their fill from the
kill before the cubs are allowed to eat at all.  In years when prey is
scarce the cubs die.  In wolf packs normally only one alpha male and
one alpha female reproduce.  He and she not only prevent lower status
males from impregnating lower status females; she, with his
cooperation (since he's bigger and stronger) prevents him (the alpha
male) from impregnating lower status females.  A male bear is 
dangerous to *his own* cubs and may kill them if the female is
unsuccessful in driving him away.  The reproductive behavior of most
predators contains elements that are counter-intuitive when viewed in
the light of evolution happening by "Everybody keep[ing] their numbers
up as high as possible."  One of the problems I have with your
examples of of vastly different male and female reproductive
strategies is the fact that nearly all of them are species who occupy
the ecological niche of being somebody's dinner.



					Carole Ashmore

manderse@orion.cf.uci.edu (Mark Andersen) (03/16/89)

In article <7376@rosevax.Rosemount.COM> carole@rosevax.Rosemount.COM (Carole Ashmore) writes:
>In article <845@microsoft.UUCP>, gordonl@microsoft.UUCP (Gordon Letwin) writes:
>> In article <7337@rosevax.Rosemount.COM>, carole@rosevax.Rosemount.COM (Carole Ashmore) writes:
>> > Let's see now.  Most ungulates fall on the 'fast reproductive rate'
>> > side; most of them are prey, not predators, and must keep their
>> > numbers up to keep the species up and the pradetors in dinners.
>> >> Everybody must keep their numbers up.  Everybody keeps their numbers
>> up as high as possible.  
>Gordon, this is simply not true.  Most predator species have built
>into their instincts some type of behavior that serves to keep their
>numbers *down*.  
>
>					Carole Ashmore

A quick search through the behavioral ecology/evolution literature will turn
up many papers arguing BOTH sides of this question. The two issues involved
are:

1) Group selection. Can behavior that is advantageous to some social group,
   but disadvantageous to the individuals performing the behavior, be 
   selected for? The answer, in general, is NO. The only likely exception to
   this has to do with the notion of "inclusive fitness" w.r.t. the
   evolution of altruistic behavior in social species. The benefactors of 
   altruistic behavior should be close relatives of the altruist, or the 
   behavior cannot be selectively advantageous. As Haldane said, "I would 
   lay down my life for two brothers or eight first cousins" (or words to
   that effect).

2) Prudent predation. It seems reasonable that predators should avoid driving
   their prey to extinction. However, this leads to a "tragedy of the commons"
   situation. To ensure his/her own fitness, each _individual_ predator 
   should eat as much as possible. In fact, the LARGE literature on predation
   seems to indicate that predator feeding rates in nature are constrained
   by the foraging efficiency of the predator, particularly handling times
   for prey items, searching efficiency, interference between predators 
   (especially important for social species), and transit times moving between
   prey patches. 

Entry-level partial reference list:

a) Ehrlich and Roughgarden. 1987. The Science of Ecology. Macmillan.
   (chapters 6, 8, and 13)

b) Futuyma. 1979. Evolutionary Biology. Sinauer.
   (chapter 12, particularly pp. 302-307 on group selection & kin selection)

c) Wilson. 1980. Sociobiology. Abridged edition. Belknap. 
   (first five chapters, esp. ch. 5)

Yours for a higher level of discussion,



			       Dr. Mark C. Andersen
			       Department of Ecology and Evolutionary Biology
			       University of California, Irvine
			       Irvine, CA 92717
			       (714) 856-5384
			       manderse@orion.cf.uci.edu

"We live in a time when men would rather be envied than esteemed."
				G. Trudeau

hkhenson@cup.portal.com (H Keith Henson) (03/29/89)

Dr Mark C. Anderson manderse@orion.cf.uci.edu in responding to a series
pointed out that the literature supports a number of ideas in 
behavioral ecology/evolution.  I agree.  Not only do different species use
different strategies, but the same one can use variation over time and
space.  If anything, I suspect that humans have evolved to use a variety of
reproductive strategies.  However, some consistancy has been observed
from the spotty human evolutionary record and some tentative extrapolations.
The lastest theory of how we and or closest relative (the chimp) diverged
discuss *provisioning*, the strategy used by birds to feed their young.
Taping male energies to obtain and feed the females high quality food (as
the forest environment changed to open grasslands) about doubled our 
ancestors reproduction capacity.  This seems to have led to such behaviour/ 
physiology as walking upright, and the family.  We still see occasional
behaviorial throwbacks as the "gang bang" (willing, not the rape variety)
which is a female chimp's way (and most likely our common ancestor's way)
of getting the males in the tribe to believe they had a stake in her baby.

evs@romeo.cs.duke.edu (Ed Simpson) (04/15/89)

An interesting article that pertains to the evolution of human
reproductive strategy:

Evolutionary social psychology and family homicide.  M. Daly and M.
Wilson.  Science 242: 519-524.  28 Oct 1988.

They are researchers in the Psych. Dept. at McMaster Univ. in Hamilton,
Ontario.  Basically they show that behavioral predictions
made from armchair cost-benefit analysis in the context
of natural selection theory are born out by extreme
manifestations of these behaviors (e.g. within-family homicide).

--------
Ed Simpson    e-mail by ARPANET: evs@cs.duke.edu
P.O.Box 3140, Duke Univ. Medical Center, Durham, NC, USA 27710
Ed Simpson    e-mail by ARPANET: evs@cs.duke.edu
P.O.Box 3140, Duke Univ. Medical Center, Durham, NC, USA 27710