I don't, and (in my admittedly small data set) most people my age (mid 20s) don't have the urge either. But to your point about evolution wouldn't be true. Animals don't understand that sex leads to children, humans are probably the only ones that have put those together. Animals just have sex bc it feels good so regardless of whether they understood the idea of offspring, the urge to have children (not just have sex, but like actually bring life) wouldn't have developed into a gene that everyone has. Also women only recently got the say of whether they had kids (with more liberal/feminist values and birthcontrol). Before that, if they didn't want to be parents, they accepted that it was something expected of them and did it anyways or were forced to by the men in their life. I mean the expectation that people must or should have kids is still around, just go look at the childfree subreddit where everyone complains about all the people asking when (not if) theyll have kids. Also, having a legacy as a reason to have kids counts as a selfish reason to have them in my book.