A close up look at the seemingly impossible life between two worlds Modern frogs descend from a lineage millions of years old. As a group, they connect us to the dinosaurs and have survived the last four global mass extinctions, yet amphibians are currently the most endangered vertebrate class. Focusing on the Pacific treefrog, Yosemite toad, and Sierra Nevada yellow-legged frog, amphibian researcher and outdoor educator Sara Dykman guides us through the delight and awe of watching a creature pivot from gills to lungs, from omnivory to carnivory, from fins to sticky toe pads. It's a miraculous lifecycle that can closely observe, only if we work to protect these amazing communities. The Studies in Nature series offers close observations, passionate research, and natural obsessions on a variety of nature-related topics. Featuring illustrations by Stacy Hsu and black and white photography, they offer big ideas in a small, giftable, and collectible package.