I, Mammal: The Story of What Makes Us Mammals

With wit and passion, Drew, a freelance writer and former neurobiologist, explores what it means to be a mammal by taking an evolutionary look at how and where mammals arose. He discusses such topics as the origin of lactation, the nature of the placenta, the evolution of warm-bloodedness, and the characteristics of the mammalian brain. He makes clear that none of these traits arose in isolation: “Individual traits can be meaningfully defined and studied in isolation, but such an approach should never blind us to the fact that every trait is a part of a greater whole.” Throughout, Drew describes organismal evolution as a multifaceted process that is difficult but not impossible to study. He presents the results of current research and offers competing hypotheses to explain many of the developmental and behavioral patterns observed. Drew vividly conveys the excitement of scientific discovery, reminding readers that there is much yet to be uncovered. He combines detailed technical information with interesting natural-history tidbits, such as that “marsupials have three vaginas—two for letting sperm in, and one for letting their joeys out.” He also niftily connects his personal experiences of fatherhood to the broader issue of animal reproduction. There’s much here to be savored by scientists and nonscientists alike. (Jan.)