As the introduction explains, this book is all about the less popular, or less well-known mammals of the world. They might be endangered, rare, or just not a popular creature but each one gets a full spread with funny pictures, basic facts and status, and interesting tidbits of knowledge.
Once you've browsed through this book, you'll know about the Lesser Fairy Armadillo, Silvery Gibbon, Russian Desman, Banded Linsang (featured on the cover), Hirola, and many more.
The only back matter is a glossary and explanation of endangered status terms (least concern, extinct, etc.) so I certainly wouldn't recommend using this for research. However, it's just right for browsing. The reading level is middle grade but the text is not so dense that interested younger children won't be able to sit still for some listening.
Verdict: A fun and unique addition to your animal book section. Recommended.