Human-mediated selection allows for the rapid evolution of crops with desired characteristics during domestication. These traits make the crops easier for humans to grow, gather, and eat (1). The iterative selection process during domestication restricts the diversity available in modern crop varieties for future generations of selection. Wild relatives of modern crops can therefore be a rich resource to mine for useful variants lost during domestication. Maize (Zea mays spp. mays) is one of the world's staple food and energy crops. The ancestor of maize, teosinte (Zea mays spp. parviglumis) (2, 3), grows in the wild in Mexico and can be crossed with maize. On page 658 of this issue, Tian et al. (4) elegantly use the genetic diversity in teosinte to discover a useful genetic sequence that can directly increase maize yields in field conditions. This suggests that redomestication of crops may identify other useful traits hidden in crop ancestors.