Imagine a lineage made up solely of women. Generation after generation, these females pilfer genes from males—not mating and reproducing in the usual way, but using sex as a means to collect genetic material that they can parcel out to their offspring in seemingly any configuration. A few genes here, a few genes there, generation after generation. It’s not some Themyscira-esque fantasy: some lady salamanders have been carrying on this way for millions of years…
“Most vertebrates that reproduce in ways that involve only females end up being sperm-dependent in one way or another,” says Maurine Neiman, associate professor in biology at the University of Iowa. Many of those lineages become “sperm parasites”, requiring sperm to penetrate their eggs in order to trigger development into embryos. They need that sperm to get things going, but they throw the genetic material away—essentially creating clone daughters while obeying the reproductive mechanics developed by their sexually reproducing ancestors.
“Superficially, these salamanders seem to have a lot in common with those other females,” Neiman says. But in fact, their “bizarre” method of reproduction has never been documented in another animal. And it’s kept them alive for much longer than other methods of makeshift asexual reproduction.
I guess this wouldn’t seem bizarre to another salamander, eh? Read on!