The series name and the cover images of these books in the “I’m the Biggest!” series suggest that each book will focus on one large animal. However, the focus is really on the title environment. Each book introduces the characteristics of its featured environment, generally illustrated by a representative example. Then it dives into plant life and wildlife, including large and small animals. In the Deserts juxtaposes the biggest desert animal, the camel, with the small Gila monster and the tiny kangaroo rat. In the Mountains discusses bighorn sheep and the Andean condor—and the much smaller alpine bumblebee. In the Prairies introduces not only large bison, but also small prairie dogs and grasshoppers. In the Rivers marvels at huge saltwater crocodiles and anacondas, as well as smaller Amazon River dolphins and tiny parasites. A world map highlights places around the globe where the type of environment can be found. The books use large, colorful photos strategically. Stunning landscapes focused on the particular environment alternate with brilliant close-ups of plants and animals. Insets offer more detail or additional examples. Each word reviewed in the back matter is also illustrated with a photo. The visual appeal will attract and hold readers’ attention as they read more about these interesting environments.

–Miriam Aronin, Booklist , 5/15/2019