With bitter herbs they shall eat it: chemical ecology and the origins of human diet and medicine

People have always been attracted to foods rich in calories, fat and protein, yet the biblical admonition that meat be eaten bitter herbs suggests that unpalatable plants play an important role in our diet. So-called primitive peoples show a surprisingly sophisticated understanding of how their bodies interact with plant chemicals, which may allow us to rediscover the origins of diet by retracing the paths of biology and culture. The domestication of the potato serves as the focus of Timothy Johns' interdisciplinary study, which forges a synthesis of ethnobotany and chemical ecology. The Aymara of highland Bolivia have long used varieties of potato containing potentially toxic levels of glycoalkaloids, and Johns proposes that such plants can be eaten without harm, owing to human genetic modification and cultural manipulation. Drawing on additional fieldwork in Africa, he considers the evolution of the human use of plants, the ways in which humans obtain foods from among the myriad poisonous and unpalatable plants in the environment, and the consequences of this history for understanding the basis of the human diet.