Domestication and diversity in Manioc (Manihot esculenta Crantz ssp. esculenta, Euphorbiaceae)

Recent work reviewed here offers new insights into the evolution of manioc (Manihot esculenta) under domestication and contributes to current scientific efforts aimed at documenting forms of environmental management, local knowledge systems, and cultural practices that enhance genetic diversity. This work shows that human and natural selection jointly shape manioc diversity through (1) the overall cultivation system, which is highly adapted to environmental pressures; (2) the knowledge, categorization, and valorization of phenotypically expressed varietal differences; and (3) the incorporation, in this clonally propagated crop, of sexually reproduced plants, which encourages intravarietal diversity and occasionally leads to the creation of new varieties, that is, new categories that are phenotypically distinct and receive a new name before being multiplied. We conclude that genetic research, when placed in an interdisciplinary context, generates new questions for anthropologists working with manioc cultivators and with tropical forest horticulturalists whose subsistence depends on other clonally propagated crops.