cher@ihlpm.UUCP (cherepov) (07/16/85)
-- I saw a segment of Leakey's BBC series on origin of man and found one piece of reasoning very unclear: One of the theories about bipedalism of our ancestors states that there were several interconnected events: bipedalism is due to increase in the number of babies cared for by one female (which encuoraged kids to walk upright - how?), the increase is due to the fact that males began providing food for females (males also could benefit from having hands free - for carrying goodies home), males' desire to run around getting food is explained by the sexual cycle of females (not having to toil as much would make them sexually receptive all the time and not just once a month). There is a great number of factors, but I fail to see how making a female more receptive would increase fertility - don't primate females become receptive every time they are fertile anyway? Even if that's not so, didn't males have to start providing before any changes in receptiveness could take place? I guess, need for male to carry food looks more like the root cause then an effect.. Even given all of these assumptions there is the quesion why this particular transformation has taken place, what environmental factors effected this ( that is, why didn't that happen 5 mil years sooner... or later) Mike Cherepov