Sztrum, A. A., et al. (2004). “Intersexuality in a pampas deer (Ozotoceros bezoarticus) – a case report.” Animal Reproduction Science , 84(3–4), 427–432. Topic: Ambiguous genitalia and gonadal differentiation in a wild deer.

Some species possess both male and female reproductive organs at the same time throughout their lives. This allows them to mate with any other member of their species, doubling their chances of reproduction. Earthworms:

Clownfish exhibit this. They live in hierarchies where the largest individual is female; if she is removed, the dominant male transitions into a female to take her place. 2. Simultaneous Hermaphroditism