Meet Eight Species That Are Bending the Rules of Reproduction

Spice up your mating life with relationship tips from rock lizards, sharks and water fleas

In times of desperation, female sawtooth sharks have been known to reproduce sans males. For other species, solo reproduction is downright vanilla. (blickwinkel / Alamy)
smithsonianmag.com

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.

So why should all-female fish have all the fun? Spice up your mating life with these relationship tips from sharks, lizards and water fleas.

For maximum fertility, try gender role-play

Some female whiptail lizards have learned to "be the man" in their relationships in order to reproduce. Researchers have found that some all-female hybrid clones actually go through the same motions as the males of the sexual variety, gripping a fellow female by the neck and then by the pelvic region. "The only difference between pseudo-copulation and true copulation is that the unisexual lizards are morphologically female (they lack hemipenes), and so intromission cannot occur between them," wrote David Crews in Scientific American in 1987.

So why do they do it? Apparently, this pseudo-sex is critical for ovarian development and females in different periods of their ovarian cycle will develop male-like behavior at different times. “By alternating sex roles they maximize fecundity and increase the efficiency of reproduction,” he wrote.

Editor's Note, March 28, 2017: This article initially stated that the Atlantic molly first became a separate species roughly 100 years ago.

Editor's Note, March 28, 2017: This article initially stated that the Atlantic molly first became a separate species roughly 100 years ago.

About Joshua Rapp Learn
Joshua Rapp Learn

Joshua Rapp Learn is a D.C.-based journalist who writes about science, culture and the environment. He has crossed the Sahara Desert, floated down the Amazon River and explored in more than 50 countries.

Read more from this author |
Tags

Comment on this Story

comments powered by Disqus