Yes, presumably this is only a result of conditions that cause reproductive competitiveness. So a better phrasing could be “Impatience and a craving for intensity leads to a higher rate of reproduction”. Presumably, because that impatience is impatience for sex. If it was impatience for say, graduation, or craving for the intensity of a cocaine high or physical violence, that would not lead to reproduction.

So it’s basically saying that having a high sex drive leads young people to reproduce. Okay.