ANN ARBOR, MICHIGAN—According to a statement released by the University of Michigan, archaeologist Raven Garvey has conducted a study on digesta, the undigested vegetal matter found in the stomachs of herbivores, and concluded that bison digesta may have played an important role in the diets of hunter-gatherers. She notes that digesta from a number of species could have been a source of calories and nutrients such as carbohydrates, protein, and fats. Garvey's models show that a group of 25 adult foragers could consume enough proteins and carbohydrates from one bison's digesta to meet the USDA’s nutritional recommendations for three days without eating any other food. "Failure to account for this underappreciated resource could have important consequences in studies that address major questions in evolutionary anthropology,” said Garvey. “Accounting for digesta as a source of both kilocalories and carbohydrates leads to predictions that differ from foraging models that do not include this resource.” She notes if hunter-gatherers had access to enough digesta, they would have less pressure to forage for fresh plants, and perhaps be able to devote time to other activities instead. To read more about hunter-gatherer societies, go to “Last Stand of the Hunter-Gatherers?”