It was when I realised I had spent half an hour reading about sponges that I realised Caspar Henderson’s modern bestiary was more than just a collection of loosely related essays. The Book of Barely Imagined Beings has the elements of a classic miscellany: an A to Z listing of 27 creatures (the letter X gets two species) with gold panels and lettering on the cover, line drawings of fantastical animals and plants on the chapter title pages and burgundy notes in the margins. Along with the narrow columns of text laid out on cream pages, it brings to mind a book that seems older, more canon, than any brand new book has a right to be.
Henderson has taken notes from Jorge Luis Borges’s Book of Imaginary Beings, a collection of fictional animals published in 1967. In his introduction, Henderson talks of being riveted by the “bravura display of human imagination” at work describing the Strong Toad of Chilean folklore, Humbaba the guardian of the cedar forest in the epic poem “Gilgamesh” and the kangaroo-like creature imagined by Franz Kafka. Bizarre as they were, these invented animals were hardly stranger than many real ones, he thought. He set about to create a 21st-century bestiary of real creatures but he would choose those animals about whom so little was known that they were “barely imagined”.
We start with the axolotl, a “disconcertingly human” salamander with a large head, fixed smile and which has the handy ability to re-grow any limbs that get severed. Given the form of the book, you might expect a natural history essay about the habitats and behaviour of the animal. That does happen, to a limited extent. Instead, Henderson gives us a meandering cultural history of how the axolotl has been become known to zoologists, from ancient Greece to medieval England and many stops besides. One moment we’re reading about early, wild theories of the evolution of the “aquatic homunculus” as an explanation for how water-dwelling creatures might have ended up on land; a few pages later Henderson is describing the ravaging effects of smallpox on the native populations of the New World during the Spanish conquest.
The chapter on barrel sponges is a discussion of symmetry, some of the oldest living creatures on Earth and, crucially, what it actually means to be an animal. “We may know that, strictly speaking, they are animals but their lack of eyes, mouths, organs and the power of movement means that they don’t really feel like animals,” Henderson writes about the barrel sponges, a bunch of tube-like creatures that are often big enough to surround a person should they want to swim inside. Like the previous chapter, we start with a brief description of a fantastical animal and we quickly jump to another place entirely – a gripping story of evolution that leaves us to ponder on the concept of “deep time”, the billions of years that life on Earth has evolved and of which humans are the merest fraction of a part. As Henderson puts it: “Human history with respect to life on Earth is as deep as the displacement of the smallest seabird floating on top of a wave over the deepest part of the ocean.”
The rest of this modern bestiary continues this pattern of natural history that segues into cultural and philosophical reflection. Henderson jumps smoothly from scientific information to history to fiction to anecdote and uses each creature as a window into the human mission to understand and interpret the world. Chapters on flatworms, leatherback turtles, yeti crabs, starfish and the honey badger all move in unexpected directions.
There is something lovely about a book that takes on so many disciplines and tackles them with confidence. This could have been a list of incomplete and unrelated facts, picked up and dipped into during a bored moment, for animal aficionados only and without an overarching theme. It’s to Henderson’s credit that he avoids all those things and presents us with something that stays in the memory long after the book is put back on the shelf, a whole that is greater than its parts.
• The winner of the 2013 Royal Society Winton Prize for Science Books will be announced on Monday 25 November
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Image by Paul Stainthorp.