ont face="Arial, Helvetica, sans-serif">Narrator: This is Science Today. Plethodontid salamanders have no lungs – instead, they breathe through their moist skin. According to Rachel Mueller, a graduate student of integrative biology at the University of California, Berkeley, these salamanders are very diverse when it comes to life history strategies.

Mueller: So some of them have an aquatic larval stage, which is sort of analogous to a frog-tadpole stage and then metamorphose and live the rest of their lives on land. Some of them have an aquatic larval stage that they retain through sexual maturity.

Narrator: Then there are some which have actually forgone the larval stage all together and are instead, fully terrestrial.

Mueller: The eggs are laid on land and out of the eggs pops a little, tiny miniaturized terrestrial salamander. So from the perspective of diversity, those are very different strategies. In salamanders, direct development, which is the case where you have an egg laid on land and a little terrestrial salamander walking out of it, only happens in Plethodontids, it’s not seen anywhere else.

Narrator: Adding to their biodiversity, Mueller recently discovered through genetic analysis that three of the four known groups of Plethodontid salamanders aren’t actually groups at all. For Science Today, I’m Larissa Branin.