Just like we do today, people in medieval times struggled with the concept of human exceptionalism and the significance of other creatures. Nowhere is this more apparent than in the medieval bestiary. Sarah Kay’s exploration of French and Latin bestiaries offers fresh insight into how this prominent genre challenged the boundary between its human readers and other animals.

Bestiaries present accounts of animals whose fantastic behaviors should be imitated or avoided, depending on the given trait. In a highly original argument, Kay suggests that the association of beasts with books is here both literal and material, as nearly all surviving bestiaries are copied on parchment made of animal skin, which also resembles human skin. Using a rich array of examples, she shows how the content and materiality of bestiaries are linked due to the continual references in the texts to the skins of other animals, as well as the ways in which the pages themselves repeatedly—and at times, it would seem, deliberately—intervene in the reading process. A vital contribution to animal studies and medieval manuscript studies, this book sheds new light on the European bestiary and its profound power to shape readers’ own identities.

From medieval bestiaries to Borges’s Book of Imaginary Beings, we’ve long been enchanted by extraordinary animals, be they terrifying three-headed dogs or asps impervious to a snake charmer’s song. But bestiaries are more than just zany zoology—they are artful attempts to convey broader beliefs about human beings and the natural order. Today, we no longer fear sea monsters or banshees. But from the infamous honey badger to the giant squid, animals continue to captivate us with the things they can do and the things they cannot, what we know about them and what we don’t.

With The Book of Barely Imagined Beings, Caspar Henderson offers readers a fascinating, beautifully produced modern-day menagerie. But whereas medieval bestiaries were often based on folklore and myth, the creatures that abound in Henderson’s book—from the axolotl to the zebrafish—are, with one exception, very much with us, albeit sometimes in depleted numbers. The Book of Barely Imagined Beings transports readers to a world of real creatures that seem as if they should be made up—that are somehow more astonishing than anything we might have imagined. The yeti crab, for example, uses its furry claws to farm the bacteria on which it feeds. The waterbear, meanwhile, is among nature’s “extreme survivors,” able to withstand a week unprotected in outer space. These and other strange and surprising species invite readers to reflect on what we value—or fail to value—and what we might change.

A powerful combination of wit, cutting-edge natural history, and philosophical meditation, The Book of Barely Imagined Beings is an infectious and inspiring celebration of the sheer ingenuity and variety of life in a time of crisis and change.