Re: poly: democracy, etc.

>>Male elephant seals, which have harems of 40 or more are gigantic, not
>>in order to dominate females, but in order to drive off the other 39
>>males who want in.
>
>This particular result follows from Fisher's explanation of sex ratios,
>without requiring any male/male combat at all. The causation goes from
>large males to unequal sex ratio to harem. ...
>Note, by the way, that if Fisher's argument is correct, there are not 39
>other males who want in.

If I recall, there are in fact lots of other male elephant seals who want
in. Can anyone verify this?

>It isn't clear to me that Brin's argument works. It apparently assumes that
>fighting is more productive, reproductively speaking, the larger the harem
>size. ... an equation showing that an increase in male size costs
>just as much in food etc. as it gains in extra reproduction through
>successful combat.

They don't actually have to fight to have large harems; they just have to
be large enough to pose a credible threat to rivals.

I agree that it is not obvious that larger harem size should correspond to
larger animals. I find it hard to think up an explanation for this.

One idea is that with large harems the top tail of the ability distribution
matters more, and genes are willing to take more chances to get up there.
Maybe larger animals are a higher variance strategy, usually getting broken
for one reason or another, but when they don't break they're really great.

Robin Hanson
hanson@econ.berkeley.edu http://hanson.berkeley.edu/
RWJF Health Policy Scholar, Sch. of Public Health 510-643-1884
140 Warren Hall, UC Berkeley, CA 94720-7360 FAX: 510-643-8614
Received on Thu Feb 12 17:39:04 1998