Excerpt from Sentient by Jackie Higgins, plus links to reviews, author biography & more

"The eyesight of these creatures is formidable;' Marshall told me. "Four hundred million years ago, one of them got hold of an optics textbook, and now they are a physics lesson on a stick." When Tyson eyeballed the world beyond his tank, he did so with what Guinness World Records calls the "most complex eyes of any animal," with the "greatest color vision." No other eye approaches the shrimp's twenty different photoreceptors. According to Marshall, "We now know that the eyes of the mantis shrimp are out of this world." However, they also tell us something about the many ways that we humans see the world.

The amount of information conveyed within light is diverse, if not infinite. To take advantage of this, mantis shrimp eyes support many different ways of seeing; they sense ultraviolet light and regular and circularly polarized light, to name a few. Similarly, science can divide human sight into separate senses. As the Introduction to this book acknowledges, experts debate exactly how many, and the number they arrive at depends on how they define a sense. In Great Myths of the Brain, while contesting "the mistaken idea that we have precisely five senses," the cognitive neuroscientist Christian Jarrett suggested that if we are classifying according to photoreceptors, human vision can be subdivided into four senses, but if we are classifying according to visual experiences, the number is far greater. Despite our disparate eyes, one can argue that we share some of the shrimp's visual senses and that its greatest visual skill, a propensity for color, illuminates how we see rainbows. To understand the full range of human color vision, one must consider its antithesis: human color blindness - not the relatively commonplace incapacity to distinguish between red and green but the complete and utter loss of every shade under the sun.

Excerpted from Sentient by Jackie Higgins. Copyright © 2022 by Jackie Higgins. Excerpted by permission of Atria Books. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.