The sex life of fish is complicated, very complicated. Did you hear that Pixar are making a sequel to Finding Nemo ? It will be released in the summer of 2016 and I wonder how closely the plot will follow nature. If Pixar have consulted a ichthyologist ( fish specialist ) then it could end up with Nemo as the female leader of his school. Bizarrely, he could even end up mating with his son and he would be both Mother and Grand Father to the next generation of clownfish.
Clownfish are protandrous and their schools are always built in a hierarchy with a dominant female fish at the top of the chain. They live within sea anemones with only one sexually mature large male and one large female who are capable of breeding. The rest of the clownfish are tiny immature males. When the female dies the mature male fish changes sex to become a female and takes her place at the top of the hierarchy. The next largest male rapidly grows to become the resident mature male.
For a 90 second overview on the sex life of clownfish have a look at this video.
From a young age I've been a big fan of all things weird and even though I love science I love the passion that people involved in the spiritual and fantastical side of things possess. I want to believe in aliens, bigfoot and the world of psychics and superheroes seems that much closer when you investigate the weird world out there.