For definitive proof that gender is indeed fluid, look no further than the animal kingdom. There, certain organisms change their reproductive identities or adapt the behavior of the opposite sex based on a time-specific need. Some animals even have working male and female genitalia.
Here are ten fascinating animals whose sex isn’t black-and-white:
1. Bearded Dragon
In a process known as sex reversal, bearded dragons have demonstrated an ability to somewhat change their sex from male to female while still in the egg. Researchers at the University of Canberra have found that these reptiles (which are still genetically male but take on the role and reproductive capabilities of the female) are indeed fertile — and even lay more eggs than their originally-female counterparts.
Researchers go on to say that this is a “naturally occurring phenomenon,” and one which may indeed be triggered by changing climates. “We had previously been able to demonstrate in the lab that when exposed to extreme temperatures, genetically male dragons turned into females,” lead author Dr. Clare Holleley said.
Beyond that, researchers hope that the dragons’ gender-bending behavior may help inform how the animal kingdom will respond to climate change.
“The more we learn about them, the better-equipped we’ll be to predict evolutionary responses to climate change and the impact this can have on biodiversity globally,” Holleley said.
2. Clown Fish
Clown fish are all born male, but that doesn’t mean they simply do without female counterparts. Rather, some — the most dominant males — turn into females (a process known as sequential hermaphroditism).
Given their role in breeding, female clown fish play an incredibly important part in the species’ survival. This importance manifests itself in the school’s physical makeup.
Indeed, the female clown fish, generally the largest fish in the school, surrounds herself with a gang of males for the purpose of breeding. If she dies, the dominant male — second in command — will change sex to replace her, ensuring the school’s survival.