Competition increases testosterone, which may be an ancient mechanism to encourage more competitive behaviors for resource allocation and reproduction.

“so it is the case that increases in testosterone promote competitive and foraging-type behaviors in humans and in nonhuman mammals”

“So the short version of this is that competition increases testosterone, and this may be an ancient mechanism whereby the androgens, such as testosterone, are feeding back to encourage more competitive-type behaviors because every species, whether or not you're talking about reproduction or other resource allocation, is involved in competition”

“however, in the short term, just competing increases testosterone independent of whether or not you win or lose”

“it's known that competitive interactions can cause increases in testosterone, in particular, in the winners of competitive interactions”

“but it's also true that competition itself can increase Androgen such as testosterone”

“So that's the rut. Like we're animals like like the red deer, you know, grow their their testicles grow. They grow weapons on their head. They become horny. They become aggressive when the females are fertile. If the females aren't fertile, all that stuff goes away. Testosterone drops. Okay? So humans are also designed to keep testosterone low which is why if there's a situation uh a competitive situation say testosterone might go up but generally it's going to be kept low when it can be but we are overnourished in western populations.”