From Philip Perry at BigThink:
The ability to run long distances and sweat—so as not to overheat, allowed our ancestors to wear out other animals. Sweating was the key factor. Consider a gazelle running over long distances and being chased by our progenitors. The fact that they can sweat and the gazelle can’t means they can last far longer in the heat of the African Savannah.
Sweating, in addition to being a highly advanced cooling system, may have also acted as a defense mechanism. Anyone who’s ever played shirtless tackle football in the summertime knows how hard it is to catch someone who’s slick and sweaty. … More.
It’s not clear, in that case, why body armor got started.
While we are on the subject of trivial explanations for human origins, intelligence, or dominance: here are (only) a few others, linked at source:
Human evolution, we are told, began in a genetic coding error (a doubling error) half a billion years ago. Or else accelerated gene regions (HARs), human specific regulation of neuronal genes, or just plain novel genes are invoked.
In other accounts, humans evolved to “outrun the fastest animals on earth.” Alternatively, parasites made us what we are. One source informs us that men evolved sturdier features due to fighting over women (and beards to demonstrate their ability). We learned to walk upright in order to hit each other.
Ah yes, walking. There is a “uniquely human” way of walking upright and there’s no shortage of theses as to why: carrying infants or scarce resources, and saving energy strut the stage. Or it is due to climate change or rough terrain? Don’t assume a “chimpanzee starting point,” counsels one expert. Talk about advice that peers would be reluctant to heed…
These explanations tell us that bipedalism offers considerable advantages. Yet humans were the only creatures to adopt it with no backward glance. If we ask why that is, we will be rewarded only with announcements of the discovery of further ancient advantages. And on that point, we are already convinced.
Bipedalism, we are told, also resulted in nakedness, because of our need to cool down. But we are assured elsewhere that nakedness evolved as a way of controlling parasites. And another source suggests that “hairier is better” for that purpose.
Similarly, the human hand is simply a byproduct of changes to the shape of our feet. Or maybe not. Did stone tools really change human hands? Darwin speculated on this, which makes the idea canonical today. Curiously, while many claim that apes use and shape tools like humans, few speculate why doing so had no such dramatic effect on their hands.
We are told by others that fighting “may have” shaped the evolution of the human hand. One academic offers, “I think there is a lot of resistance, maybe more so among academics than people in general — resistance to the idea that, at some level humans are by nature aggressive animals.” Resistance? Really? Among academics and pundits, that is surely the conventional view!
And the human brain? Some say we evolved large brains alongside small guts, but another research team found no such correlation. Alternatively, fluid societies (relative to chimps) explains it. And, according to some, mental illness helped. Chimpanzees’ improved skills throwing excrement are also said to provide hints about human brain development. (The ability to throw projectiles at very high speeds is apparently unique to humans.) Our ancestors had to grow bigger brains anyway, we are told, to make axes and hunt something besides elephants. Collective intelligence (“ideas having sex”), whatever that means, has been really important to human evolution as well.
The obvious problems with all of these disunited and discordant theses can be summed up for convenience as: 1) If some aspect of chimpanzee behavior explains matters, why didn’t it produce the same result in chimpanzees? 2) If mere advantage (which every primate seeks) explains a development like the human mind, why did only humans experience it? More.
See also: Human origins: The war of trivial explanations
The Science Fictions series at your fingertips: Human evolution