The Light Eaters: How the Unseen World of Plant Intelligence Offers a New Understanding of Life on Earth

by Zoë Schlanger

Recently, as I came across in my reading, researchers had found promising indicators of memory in plants. Others found that a wide variety of plants are able to distinguish themselves from others, and can tell whether or not those others are genetic kin. When such plants find themselves beside their siblings, they rearrange their leaves within two days to avoid shading them. Pea shoot roots appeared to be able to hear water flowing through sealed pipes and grow toward them, and several plants, including lima beans and tobacco, can react to an attack of munching insects by summoning those insects’ specific predators to come pick them off. (Other plants—including a particular tomato—secrete a chemical that causes hungry caterpillars to turn away from devouring their leaves to eat each other instead.) Papers probing other remarkable behaviors were growing from a trickle to a fairly robust stream. It seemed like botany was on the verge of something new.