The Amazon Molly: A Unisexual Species

Though their namesake, the Amazon warriors, did have males in their tribes, the Amazon Molly has figured out a way to be a unisexual species. It is a species made entirely of females, who only sire female offspring. If you guessed this was achieved through asexual reproduction, you’re right but that’s not the whole story: the Amazon Molly still needs to mate with a male to reproduce. What’s going on here?

The Amazon Molly reproduces using gynogenesis, which ultimately means that they reproduce by creating clones of themselves. This type of reproduction also means that they need sperm to kick start the cloning process.

The Amazon Molly claims this sperm from P.latipinna, P. Mexicana, or P. latipunctata, which are closely related Molly fish. Unlike sexual reproduction, none of the male’s DNA is incorporated into the Molly’s eggs during gynogenesis; the sperm is simply used to start embryonic development so the Amazon Molly can begin making the next generation of herself. This type of gynogenesis is classified as sexual parasitism.

Interested in learning more about the mating behaviours of different plants, animals, and fungi? Check back here for more Mating Mondays.


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