Leeching in medical practice dates back at least to the Ayurvedic period in South Asia, moving westward with notions of the humoral theory of disease and health. Though the use of leeches was noted both in Hippocratic and Galenic writings of ancient Greece, and while their use carries a medieval character, the exploitation of the medicinal leech reached its zenith in 19th-century Europe—so much so that leeches were the focus of the first intensive efforts at species conservation. Rather than being indicative of outdated and poorly informed surgical procedures, leeches have played key roles in the rise of clinical medicine, dialysis, and even microsurgery and hematology. Current research seeks to uncover the genomic basis of the evolution of sanguivory and the full suite of bioactive peptides in this charismatic group of animals. Mark Siddall, a curator in the division of invertebrate zoology of the American Museum of Natural History, curated the recent exhibitions “The Power of Poison” and “Life at the Limits.”
