The Zoologist's Guide to the Galaxy

We are unprepared for the greatest discovery of modern science. Scientists are confident that there is alien life across the universe yet we have not moved beyond our perception of 'aliens' as Hollywood stereotypes. The time has come to abandon our fixation on alien monsters and place our expectations on solid scientific footing.

Using his own expert understanding of life on Earth and Darwin's theory of evolution - which applies throughout the universe - Cambridge zoologist Dr Arik Kershenbaum explains what alien life must be like: how these creatures will move, socialise and communicate.

For example, by observing fishes whose electrical pulses indicate social status, we can see that other planets might allow for communication by electricity. As there was evolutionary pressure to wriggle along a sea floor, Earthling animals tend to have left/right symmetry; on planets where creatures evolved mid-air or in soupy tar they might be lacking any symmetry at all.