As currency, beverage, and divine plant, cacao (Theobroma cacao, family Sterculiaceae) has played an important role in ancient Central American cultures. To the Mayans, the plant was a gift from their gods—implied in the name Theobroma, Latin for "food of the gods." The dried seeds were important in Aztec society as a unit of currency (used in the Yucatan Peninsula until the 1850s), and as part of a drink reserved for the nobility. Today, cacao is probably best known for the sweet, rich food produced from the seeds called chocolate.

Cacao is typically a small-to medium-sized deciduous tree of the New World tropical forests. The small, cream-colored flowers are produced directly from the woody trunks and branches of the tree, not in the leaf axils, where most other flowering plants produce flowers. Following pollination, pods are produced, ranging in color from green through yellow to red-brown. Each...