>I would point out something I read in an anthropology book once on
>polyandry. It apparently is limited to brothers having the same wife and
>doesn't seem to work with unrelated males. The speculation was that only
>the close ties of two brothers provides the stability required for such a
>situation.
I read about a year ago or so in the New Yorker about the decreasing sperm
count in Western males, and that if the trend continues there is a
(supposed) danger of under-population. I can't recall the date, and I don't
believe I have the issue any more. But should such a scenario arise,
polyandry would certainly offer an interesting solution, and for the same
reasons, I imagine, polygyny is/was practiced in some quarters--to ensure
healthy progeny.
--csc