Re: Dissecting the Aquatic Ape: Bipedalism

8 Aug 1996 16:20:53 GMT

Leonard Timmons ( wrote:
: HARRY R. ERWIN wrote:
: >
: > Leonard Timmons ( wrote:
: > : I have noted that among most species, when males fight they try to determine
: > : one another's ability to inflict damage without actually doing so. I have
: > : heard of the survival advantages to this strategy and thus the reason for
: > : its evolution. However, when I look at us and our ancestors, I see animals
: > : that are just about completely unarmed. We cannot really inflict damage on
: > : one another of the same magnitude as one horned animal goring another. I
: > : don't know why we lost our incisors, but the prevalance of alliances among our
: > : ancestors may have eliminated even these (I guess).
: >
: > This game is chaotic, by the way, if the strategies are learned. It
: > converges rapidly to an ESS if learning is not important.

: Since you mention the chaotic nature of this game, I assume that there
: are
: computer simulations of these strategies that show this chaotic
: behavior.
: Is this correct?

Yes. Presented at Cambridge in 1990 and finally being published this year
by Routledge.


: In the ESS studies that you did, did you consider the slow adoption of a
: strategy, or did your models begin with strategies that are executed
: perfectly by the participants? Since chaotic behavior often results
: from
: systems that are overdriven, a new strategy which is suddenly executed
: perfectly by the participants might lead to a chaotic solution, but at
: some low level of proficiency, the solutions might be marginally stable.

Both slow and fast adoption. Yes, learning overdrives the system,
throwing it into chaos. Genetic evolution goes to a fixed point.

Harry Erwin, Internet:, Web Page:
49 year old PhD student in computational neuroscience ("how bats do it" 8)
and lecturer for CS 211 (data structures and advanced C++)