section_path: Sex-determination systems/Environmental/Sequential hermaphroditism
section_name: Sequential hermaphroditism
paragraph_text: Sequential hermaphroditism
  
  Some species can change sex over the course of their lifespan, a phenomenon called sequential hermaphroditism.
  
  Teleost fishes are the only vertebrate lineage where sequential hermaphroditism occurs. In clownfish, smaller fish are male, and the dominant and largest fish in a group becomes female; when a dominant female is absent, then her partner changes sex from male to female. In many wrasses the opposite is true: the fish are initially female and become male when they reach a certain size.
  
  Sequential hermaphroditism also occurs in plants such as Arisaema triphyllum.