10 animals that can change their gender: Nature's gender fluidity

Clownfish are born male and live in small groups led by a dominant female. When the female dies, the largest male changes into a female to take her place, and another male steps up as the breeding partner. This ensures the continuity of the breeding pair.

Wrasses are reef fish where the largest female can transform into a male if the dominant male is lost. This change ensures that there is always a male available to mate with the females in the group, maintaining reproductive success.

Parrotfish can change their gender as they age. Some species start as females and later become males, which helps them maximise their reproductive opportunities throughout their lifespan. These changes are often accompanied by a change in coloration.

Sea bass can switch between male and female multiple times throughout their lives. This bidirectional hermaphroditism allows them to adapt to changing social structures and optimise their reproductive success depending on the availability of mates.

Moray eels have the ability to change their gender based on the needs of their population. If there are too many males or females, some individuals will switch to balance the gender ratio, ensuring that reproduction can continue efficiently.

Gobies are small fish that can change their gender in response to environmental conditions. For example, if a goby finds itself in a situation where mates are scarce, it can switch gender to increase its chances of reproducing.

Slipper limpets live in stacks, with the bottom individuals being female and the top individuals being male. If a male finds itself at the bottom of a stack, it can change into a female. This sequential hermaphroditism ensures that there are always both genders available for reproduction.

Many coral reef fish can change gender depending on their species. Protogynous fish start as females and become males, while protandrous fish do the opposite. These changes help maintain a balanced population and optimise mating opportunities.

Flatworms are hermaphrodites that can change their gender during mating. They engage in a behaviour called "penis fencing," where each flatworm attempts to inseminate the other. The one that becomes inseminated acts as the female, while the other takes on the male role.

Some shrimp species, like the Lysmata, are born male and become female as they mature. This sequential hermaphroditism allows younger, smaller males to mate with larger, older females, ensuring successful reproduction as they grow.