杏吧原创

IN Walking Sideways, Judith Weis treads a line between popular science and biology textbook for an account of crab diversity, ecology, behaviour and anatomy, with a little on fisheries thrown in at the end. Weis celebrates crabs鈥� many adaptations to deal with different depths, temperatures, salinity and oxygen levels both in and out of the sea.

The book is filled with fascinating facts 鈥� why crab blood is blue, for example, and why the horseshoe crab isn鈥檛 a crab. She also introduces plenty of unique characters, including the Yeti crab, whose pincers are covered with hair-like filaments full of bacteria, or the coconut crab, that drowns if submerged. Then there鈥檚 the Caribbean land crab, which is so averse to water it throws its eggs, which need water to hatch, off sea cliffs to avoid getting wet.

The beauty is in the weirdness. Crabs smell with their feet, which seems fortunate given they pee with their heads. Land crabs can reprocess their urine, passing it back over their gills to reabsorb salts before excreting it out a hole near their antennae. Delightfully, the scientific symbol denoting the 鈥渇inal excretory product鈥� is P.

鈥淐rabs smell with their feet, which seems fortunate given that they pee with their heads鈥�

Though some passages read like lists of examples, and the prose can be clunky (repeated references to 鈥渢hese sideways-walking crustaceans鈥� had me cringing), Weis definitely shares her sense of wonder, and leaves you with the impression that you have only scratched the exoskeleton.