California sheephead can change their gender

The most unusual attribute to this peculiar-looking fish is that it can turn into a fully functional male later on in life. All California sheephead are born female, but some will switch to being males. A number of environmental factors decide as and when this happens. For example, when a dominant male dies, a large female will change gender and take over proceedings. It will then take on the feeding patch already established by the previous dominant male of the reef and assume power. Keeping things in order as though nothing has happened, the new male will then breed with the females.

There are several reasons suggested why this strange transformation happens, most notably if the fish stands more chance reproducing as a member of the opposite sex. The transitional period between genders can take anything from two weeks to several months.