Welcome back to the series on World Building. Today we’re going to talk about Social Life. This will be the first of three installments.

This first installment is going to deal with birth through adulthood, how your people—be they humanoid or alien—grow up, how they are shaped in and by their world.

The first question you must ask yourself, assuming you are not writing about actual human beings, is how your people come into existence. Are they born? Are they formed? Are they hatched? For S...