The male surplus for 0-20 is there the entire century and is human nature. Humans have slightly more male babies (1.07x?) because men are more likely to engage

The male surplus for 0-20 is there the entire century and is human nature. Humans have slightly more male babies (1.07x?) because men are more likely to engage in risky or unhealthy behavior leading to early death. You can see the female surplus start around 50+. There's some evolutionary equilibrium that keeps human (and some other animal) populations this way; averaging 1:1 ratio with an early male surplus and later female surplus.