frogs

In one corner, we have the "hairy" frog, Trichobatrachus robustus, hailing from Cameroon.

In the other corner, meet the Spanish ribbed newt, Pleurodeles waltl, hailing from the Iberian peninsula.

Which skin-busting, bone-poking amphibian will win the PopSci deathmatch?

Hara Woltz's clients don't say much -- mostly just ribbit. A landscape architect and biologist at Columbia University, Woltz has undertaken the daunting task of creating road-crossing tunnels for amphibians and reptiles, based on different animals' preferences for different tunnel attributes. Building herpetological crosswalks might seem absurd, but the stakes are high: nearly one-third of the world's amphibian species and many of its reptiles are spiraling toward extinction due to habitat loss and fragmentation from human development.

Embryos of the red-eyed tree frog have developed an interesting strategy to survive on a patchy supply of oxygen. To permeate the normally oxygen-deficient eggs, oxygen must first pass through a strong outer membrane. But even though tiny hairs called cilia stir the fluid inside these quarter-inch-diameter eggs, most of the oxygen is near the eggs’ exposed surface.

Lots of amphibians (a third to a half of all species) are dying, and their deaths are the breaking-edge of what many scientists are calling the first mass extinction since the dinosaurs checked out 65 million years ago, researchers say in a new paper published online in the Journal Proceedings of the National Academy of Sciences.