Humans may have saved pumpkins, squashes and gourds from an Ice Age extinction, researchers say online November 16 in the Proceedings of the National Academy of Sciences. Genetic analysis of 91 ancient and modern gourds (Cucurbita sp.) suggests that people began cultivating the plants nearly 10,000 years ago.
Wild gourds are very bitter, so the team tested genomes from 46 modern mammals for a gene related to tasting bitterness. Smaller mammals had more copies of this gene, suggesting that ancient small mammals probably rejected the fruit, while megafauna like mastodons helped spread early Cucurbita seeds.