Where did dinosaurs come from?

Gr 3-5-This slim, colorful title is all about evolution, but, sadly, it never addresses what the term means and how it works. The brief text tries to cover everything from 3.5 billion-year-old stromatolites to the giants of the Cretaceous period but makes some jumps that might seriously puzzle neophytes to the evolutionary branchings of life. Think of why the large dicynodonts and gorgons of the late Permian ended up as squirrel-sized mammals in the Cretaceous, for example. The colorful illustrations portray the ever-evolving parade of interesting critters (some sure to be unfamiliar to many young readers), and all those with "ID tags" are described in the glossary (which contains no definitions per se). Nicely, one clear combo of text and illustration demonstrates the essential differences between the skulls of a Gorgonops and an Archosaurus, showing how that difference defines dinosaurs appearing higher on the evolutionary tree. Covering the development of tough-shelled eggs and the emergence of huge true sauropods, the interesting text is sure to raise a plethora of questions in readers not up on the evolutionary process. Eye-catching and on the ever-hot topic of dinos, this slender book will certainly attract children's attention, but they will be left asking for more information.-Patricia Manning, formerly at Eastchester Public Library, NY (c) Copyright 2011. Library Journals LLC, a wholly owned subsidiary of Media Source, Inc. No redistribution permitted.

After a brief introduction to natural history, the book concentrates on the period from 330 million years ago to 65 million years ago, from the appearance of amniotes (four-footed vertebrates who lay eggs on land), to the split between mammal ancestors and reptiles, and through to the myriad dinosaur species that thrived in the Mesozoic Era. Zoehfeld is remarkably precise with language, no easy feat when writing on this topic for beginning readers, providing outstanding explanations of key evolution concepts in the finest tradition of the series. The color illustrations include anatomical details, a helpful phylogenetic timeline, and imagined portrayals of dinosaurs active in verdant habitats. A glossary (in tiny type) is appended. DANIELLE J. FORD (c) Copyright 2010. The Horn Book, Inc., a wholly owned subsidiary of Media Source, Inc. No redistribution permitted.