NEVER HOME ALONE

A paean to biodiversity by a biologist who sees salvation in cultivating life’s infinite variety.

Dunn (Applied Ecology/North Carolina State Univ.; Never Out of Season: How Having the Food We Want When We Want It Threatens Our Food Supply and Our Future, 2017, etc.) reports on an impressively wide variety of fascinating creatures all over the world. For example, your hot water heater is home to the same thermal-loving bacteria found in hot springs. That cricket in the basement lives a meager existence, mostly eating dead stuff. The showerhead in your bathroom is a perfect biofilm sheltering bacteria not killed by chlorination. The learning quotient is high in this fact-filled text, but there are also opportunities for learning more, since, as the author notes, specialists tend to study exotic bugs in faraway places, ignoring what is literally underfoot. Who knew that those camel crickets in the basement have gut bacteria that could devour industrial waste? Dunn estimates that there are 250,0000 species that live with us, and most are benign or beneficial. Yet we often choose to kill them, with pesticides for the cockroaches, fleas, flies, and mosquitoes, and antibiotics for disease pathogens, resulting in resistance as well as much collateral damage to other life. Our zeal for sanitation has led to an increase in allergies and asthma, manifested by an overreactive immune response known as the hygiene hypothesis, for which Dunn presents good evidence. The author also discusses pets; whatever the cat dragged in might alter readers’ behavior toward their feline friends. For a change of pace, Dunn provides a chapter on the fermenting bacteria and yeasts that give us beer, wine, and foods like kimchi and sourdough bread. The surprise is that long-time preparers of these foods impart unique flavor to the products because their hands acquire some of the same fermenting species not normally found on skin.

Of course we must chlorinate our water, wash our hands, get vaccinated, and so on, Dunn argues persuasively and entertainingly. But we also need to relax and cultivate biodiversity for the good of all life on Earth.