SKELETON KEYS

A cheerful popular-science romp through the matter that makes up our skeleton.

Writers on human body parts usually concentrate on the heart, lungs, brain, and reproductive organs. Science writer Switek (My Beloved Brontosaurus: On the Road with Old Bones, New Science, and Our Favorite Dinosaurs, 2013, etc.) leaves the beaten path to deliver a fun explanation of the history, function, and cultural meaning of bone. As the author notes early on, life was squishy for billions of years. Less than 500 million years ago, bone “got its start as rigid plate armor on the outside of a primordial fish, but as the pieces sunk inside they became an interlocking framework that never shifts by itself, yet…allows for the sensational range of motion our species is capable of.” Bone is hard but not too hard. It contains about 30 percent collagen, identical to the connective tissue that makes up our ligaments and tendons. The other 70 percent is a mineral called hydroxyapatite (tooth enamel, much harder, contains more than 90 percent). Switek does his duty by bone science, but his heart is in bone disease and bone culture. The best fossils (human included) contain fractures and cut marks that reveal how the creature lived and perhaps died. Ancient bones regularly turn up as jewelry and building material; converting human skulls to drinking cups and art objects has a long history. The author gives King Richard III’s recently exhumed bones their own chapter. In the 19th century, collectors assembled thousands of skulls and expressed confidence that they revealed the essence of race, character, and intelligence. It’s unlikely that most readers believe they were right, but the author goes to great length to show that they weren’t.

Switek belongs to the science-shouldn’t-be-boring school of writing, but readers who can tolerate his steady stream of whimsy, jokes, and drollery will receive a painless, mostly illuminating education on his subject.