The Zoologist’s Guide to the Galaxy: What Animals on Earth Reveal About Aliens— and Ourselves
(Penguin, $28)
Humans have long gazed into the night sky wondering if we are alone, said David Barash in The Wall Street Journal. Arik Kershenbaum’s new book takes “a novel and rewarding approach to this question,” looking beyond whether extraterrestrial life exists to instead examine what forms such life would probably take. His theories are grounded in the idea that life anywhere would evolve by the process of natural selection. But don’t assume that the Cambridge University zoologist means that any alien life would have physical features we’d recognize. He focuses less on looks than on likely traits, such as sociality, cooperation, language, and intelligence. The result is “a wonderful mix of science-based speculation and entertaining whimsy.”
For all its diversity, life on Earth, we’re reminded, is also remarkably consistent, said James McConnachie in The Sunday Times (U.K.). Like many of this planet’s inhabitants, aliens would probably be bilaterally symmetrical. And they’d be more likely than not to use something like wings, fins, or legs to move about. Kershenbaum, who specializes in animal vocalizations, also speculates that advanced alien life would be capable of emiting a sound akin to a scream. Elsewhere, he can be often overly cautious with his speculations. “What saves the book,” however, “are the animal examples.” We learn of a shark whose buoyancy allows it to float upward to its prey. We hear about a marsupial whose males mate so furiously that they die of exhaustion.
If extraterrestrials are more advanced than we are, all bets are off, said Adrian Woolfson in Science. “There may be species that have learned to rewrite their own genomes,” in which case they are unbound by the rules of natural selection. Barring that scenario, though, Kershenbaum has prepared us well for our first interspecies “hello”—even if we wind up detecting no response. Life on Earth, he reminds us, has already supplied examples of creatures that read magnetic fields and communicate via electrical charges.