First humans walked upright because it was so hot

The post was probably removed by the moderators. Which is why you don't see it To answer your first question, the answer is yes, heat rises. But to anyone who's ever been to the desert will tell you the difference in air temperature standing up or laying down is insignificant. What's more significant is the total area of body exposed to direct sunlight. In quadrupeds there is more direct exposure than in tall skinny bipeds. yeah i can understand that,think of the beach,you dont wanna burn your hands and your feet .

copa. i am surprised you didnt think of this reason for standing up, standing up exposes more body surface to the wind. which means sweat evaporates faster, thus cooling the body faster,

the best reason for standing up and walking was to carry things. chimps walk upright when they carry large things. as for the op i agree if that is the reason how come no one else did it. As Lost Shaman already pointed out, many species did indeed become bipedal, noticeably, birds. The Ostrich appears to be a more successful Biped then we are.

copa. i am surprised you didnt think of this reason for standing up, standing up exposes more body surface to the wind. which means sweat evaporates faster, thus cooling the body faster, There appears to be many reasons, sex also being in the mix, which makes the adaption more successful, therefore it was an adaption that was carried on? Like Mattshark said, this is hardly breaking news.

As Lost Shaman already pointed out, many species did indeed become bipedal, noticeably, birds. The Ostrich appears to be a more successful Biped then we are. birds kept their tails for balance. as for sex it supposedly adjusted to our upright stance.

birds kept their tails for balance. as for sex it supposedly adjusted to our upright stance. Yes, for balance in the air when flying. The tail of the ostrich isn't doing much, and thus small. I don't see what any position during sex has to do with evolution or being bipedal. Bonobo chimps have sex in the most various ways and positions, they can walk as bipeds for an extented period of time (mostly when carrying food), but are quadrupeds for most of the rest of the time. And about what you said, that humans can almost walk forever... The Bushmen or Khoisan of Southern Africa are able to outrun... [More]

As Lost Shaman already pointed out, many species did indeed become bipedal, noticeably, birds. The Ostrich appears to be a more successful Biped then we are. birds may be biped, but they walk like they had four legs on the ground. so that doesnt really count for what we are talking about

copa. i am surprised you didnt think of this reason for standing up, standing up exposes more body surface to the wind. which means sweat evaporates faster, thus cooling the body faster, **Shrugs**, first you'd need to provide evidence that the difference in height does increase evaporation cooling. I'm not so convinced, but it would be worth looking into. As I've said now on here for a few years, being a biped isn't one of those "caused by one selective pressure" kind of thing. Major changes to bauplan need major selection acting up on them, hence many contributing reasons for the adaptation.

**Shrugs**, first you'd need to provide evidence that the difference in height does increase evaporation cooling. I'm not so convinced, but it would be worth looking into. As I've said now on here for a few years, being a biped isn't one of those "caused by one selective pressure" kind of thing. Major changes to bauplan need major selection acting up on them, hence many contributing reasons for the adaptation. personally as far as coping with the heat they could have just gotten out of the sun like everyone else does.

personally as far as coping with the heat they could have just gotten out of the sun like everyone else does. That'd be all well and good if we were nocturnal predators or you don't mind eating for a few hundred days a year. But I'm guess the need to feed and survive drove our ancestors out into the sun.