Clown fish, fish cobra, wren… are strange animals that have the ability to unintentionally change gender. In addition to natural causes, negative impacts from environmental pollution also cause the sex of these species to change.

1. Clownfish

Clownfish is a typical marine animal that is easy to recognize thanks to its orange body with 3 prominent white lines. Clownfish are hermaphrodites.

When born, all clownfish are male, but when they mature and mate, the more dominant fish will turn into female.

2. Wren

The wren in the picture is extremely rare because it possesses both male and female physical characteristics. Half gray fur is characteristic of females, while half bright red is characteristic of males. Wrens with both sexes are quite a rare variation, they are often estranged from their peers.

3. Ribbon eel

The ribbon eel is a special creature, capable of changing gender (protandric) and color according to each life stage. When it is young it is male, when it grows up it changes into a female.

4. Fish cobra

Many female cobras can fertilize themselves without a male snake. This means that females can reproduce on their own and maintain normal species without the need for males.

5. North American green frog

Due to the influence of herbicides on accumulated runoff and rivers, lakes, etc., more and more male North American green frogs are having unwanted sex changes. Many male frogs are transformed into complete female frogs with fully functional reproductive organs.