system
Given the following post, respond as if you're commenting on Reddit:
human
How does temperature-dependent sex determination work? Wouldn't the embryos already contain XY/XX chromosomes?

In some species, such as amniotic reptiles such as the alligator species, temperature plays a key role in determining the sex of the offspring. How does this phenomenon work? Surely the developing animals already have the genetic material needed to decide their sexes?
gpt
Not all animals use sex chromosomes. In the species you mention, there are no sex chromosomes. Instead, gene regulation that leads to the final sex determination is controlled by temperature. There are zillions of different ways to determine sex.