How do clown fish change sex and how does their body “know” when to?


Sequential hermaphroditism in fish is fascinating but I have no idea how it works, especially chromosome wise. Does it happen to all clown fish or is it triggered by environmental factors?

In: Biology

Chromosomes aren’t required to determine sex, it’s just the method a lot of mammals and birds primarily use.

Clown fish all start off male, and then if there are no females around, then the mature male transitions to female, and one of the adolescent males matures into an adult male. The exact mechanism isn’t known, I think, but will involve hormone signalling.

Sex is just based on expressed hormones in the body, depending on which set of hormones are expressed, the body will change to that form.