All-Female Salamanders Have Superior Powers of Regeneration

The Amazons were a mythical race of warrior women who, in one version of the story, removed their right breasts to be more hardcore. But an all-female race of salamanders doesn't suffer from missing body parts. In fact, these animals have super-powered regeneration: when they lose an appendage, they can grow it back much more quickly than other salamanders do. The secret lies somewhere in the salamanders' bizarre genetics. "They sort of defy definition," says Rob Denton, a graduate student in ecology at Ohio State University. The amphibians he studied aren't even a real species, to start with. They're an ancient lineage (like the Amazons) that can be traced back about 6 million years. Rather than the two sets of genes most animals have, these salamanders may have three or more sets. They're all females, and usually reproduce by cloning themselves. But they don't totally ignore males. They'll mate with ...