The female is the largest fish, the breeding male is the second largest and the rest are sexually immature males.
Males can turn into females if the alpha female dies. If this happens the dominant male will get the first choice of food and begin to gain weight, ultimately becoming female. She will then choose a breeding partner, which is usually the next largest and most aggressive male available. The two will then pair off and breed.
Clownfish have a symbiotic relationship with the stationary, bush-like animal, “sea anemone”.
Wrasses and moray eels also have the ability to switch gender roles.