When a species is facing extinction, it takes an enormous human effort to stave it off. Case in point: the painstaking campaign to save the frosted flatwoods salamander.

In northern California, a group of volunteers spend every night from late fall through winter as crossing guards–escorting migrating salamanders across a rural road. 

The snake-like amphibian is native to Brazil. Researchers say the milk in many ways resembles that produced by mammals.