Meet Eight Species That Are Bending the Rules of Reproduction

When it comes to getting creative in the bedroom, we humans may think we’re the experts. In fact, we’ve barely scratched the surface of how varied and multifaceted reproduction can be—just look at species that do the deed through kinky-sounding strategies like sperm sequestration, “virgin births” via cloning or even hybridizing with other species. These may sound like show plots of a new series on the Space Channel, but they’re actually just some of the many tricks that Mother Nature uses to stay a few steps ahead of Cosmopolitan Magazine’s sex tips.

Moreover, some of these unconventional methods are making scientists rethink the basic tenets of reproductive biology, says Ingo Schlupp, a professor of biology at the University of Oklahoma. His study subject, the asexual Amazon molly fish, defies the so-called rules of reproduction by making perfect clones of itself, sans males. With such a lack of genetic diversity, these finger-sized fish should have been wiped out by disease long ago, Schlupp points out.

“How on earth do these guys survive for such a long time without any recombination?” he says. “To me that’s a real head scratcher. Here’s a species that doesn’t [recombine their genes every generation] and theoretically should have been dead many thousands of generations ago, but yet they’re living happily.”

We still haven’t unraveled all the mysteries. But one thing’s for certain: The more we learn about “alternative “reproduction strategies across species, the more we realize that many of them might not be so alternative after all. Now that they know what to look for, biologists are finding more and more cases of strange and hitherto unknown forms of animal procreation. In other words, baby-making outside the “traditional” male-female pairing could be far more widespread than we humans are inclined to think.

Roughly 100,000 years ago, in a romantic lagoon near Tampico on Gulf side of Mexico, two distinct fish species—a sailfin molly male and an Atlantic molly female—came together in an unlikely union. The colorful pair gave birth to the Amazon molly: an all-female, asexually reproducing mini-carrot length fish named after the all-female tribes of Greek legend, according to Schlupp of the University of Oklahoma.

Yet while these Amazons need no male genetic material to reproduce, they’re not entirely independent. To kickstart their reproductive systems, they still need sperm. In a bid to find a suitor into this kind of thing, Amazons will actually disrupt mating processes between sexually reproducing mollies they come across in an effort to steal the male’s seed from his erstwhile mate—by literally squeezing in between the pair.

“They kind of butt in and then it’s almost as if they’re hoping to get the mating that was meant for another female,” Schlupp says. “The males that these Amazon mollies are mating with really have to get up close and personal with the Amazon mollies. These fishes have a specialized fin that they use to transfer sperm—we’re actually talking about real copulation. It’s not like a mass spawning where some parasitic female swoops in and gathers some sperm.”