link (http://www.sciencealert.com.au/news/20071604-15037.html)
"Individual wrasses first function as females. At around two years of age, and approximately 18cm in length, they mature and begin producing eggs.
"They continue to function as females until approximately four to five years of age, when they are about 28cm long, then change sex and become males in a process known as sequential hermaphroditism.
"Within each territory a single male has a harem of up to 10 socially ranked females with the largest, highest ranking female likely to be the one to change sex after the male dies.
I think a researcher talked about this in her book called Darwin's Rainbow. :3 Nice find.
-- Brede