The Zoologist's Guide to the Galaxy

A fun, and thoroughly biological, exploration of possible and impossible alien beings. If you'd love to know what real aliens from other planets might really be like, this is the book for you

Susan Blackmore, author of Seeing Myself

If you don't want to be surprised by extraterrestrial life, look no further than this lively overview of the laws of evolution that have produced life on earth.

Frans de Waal, author of Mama's Last Hug

Evolutionary theory helps us explain patterns in the past, and combined with a rich understanding of natural history and biodiversity, predict what might be discovered in the future. Arik Kershenbaum takes us on a joyous voyage of animal diversity and illustrates the singular importance of natural selection in explaining life - here on Earth - and what will likely be discovered throughout the galaxy. A stimulating read!

Daniel T. Blumstein, Professor of Ecology and Evolutionary Biology, University of California Los Angeles

Surveying the deep-time of evolution on Earth and his own cutting-edge research into animal communication, Kershenbaum provides a fascinating insight into the deepest of questions: what might an alien actually look like

Lewis Dartnell, author of Origins

When we search for aliens, what are we searching for? If life exists on other worlds, it might look very different to life 'as we know it', but Arik Kershenbaum makes a persuasive and entertaining case that we needn't be completely in the dark. There are some rules that all beings with a claim to be alive must observe, and for which life on our planet can serve as a guide. This is an eye-opening and, above all, a hopeful view of what - or who - might be out there in the cosmos

Philip Ball, author of Nature's Patterns

The book crawls with curious facts . . . [Kershenbaum] is fascinating on how aliens might communicate

James McConnachie, The Sunday Times

This is no mere frivolous exercise in arm-waving (or tentacle-waving) and baseless speculation. Instead, what emerges is a fascinating plunge into the deep-time history of life on Earth and animal evolution in all its glorious diversity . . . To comprehend the alien is to know thyself

Lewis Dartnell, The Times

I love The Zoologist's Guide to the Galaxy by Arik Kershenbaum. Although it sets out to be (and is) about alien life, what emerges is a wonderfully insightful sidelong look at Earthly biology

Richard Dawkins, via Twitter

Kershenbaum argues that the key to understanding cosmic zoology is natural selection. This, he maintains, is the "inevitable mechanism" by which life develops, and therefore it's "not just restricted to the planet Earth" or even to carbon-based organisms. However alien biochemistry functions, "natural selection will be behind it." From this premise, Kershenbaum says, it follows that life on other planets will have evolved, if not along the same lines as life on this planet, then at least along lines that are generally recognizable. On Earth, for instance, where the atmosphere is mostly made of nitrogen and oxygen, feathers are a useful feature. On a planet where clouds are made of ammonia, feathers probably wouldn't emerge, "but we should not be surprised to find the same functions (i.e. flight) that we observe here." Similarly, Kershenbaum writes, alien organisms are apt to evolve some form of land-based locomotion - "Life on alien planets is very likely to have legs" - as well as some form of reproduction analogous to sex and some way of exchanging information: "Aliens in the dark will click like bats and dolphins, and aliens in the clear skies will flash their colours at each other." . . . On Earth, many animals possess what we would broadly refer to as "intelligence." Kershenbaum argues that, given the advantages that this quality confers, natural selection all across the galaxy will favor its emergence, in which case there should be loads of life-forms out there that are as smart as we are, and some that are a whole lot smarter. This, in his view, opens up quite a can of interstellar worms. Are we going to accord aliens "human rights"? Will they accord us whatever rights, if any, they grant their little green (or silver or blue) brethren? Such questions, Kershenbaum acknowledges, are difficult to answer in advance, "without any evidence of what kind of legal system or system of ethics the aliens themselves might have."

Elizabeth Kolbert, New Yorker

Entertaining and thought provoking

Science magazine

A wonderful mix of science-based speculation and entertaining whimsy

David P. Barash, Wall Street Journal