"Doedicurus" was likely a grazer, but its teeth and mouth, like those of other glyptodonts, seem unable to have chewed grass effectively, which may indicate a slow metabolism. "Doedicurus" existed during the Pleistocene. Before this, South America had been isolated from the rest of the world, but the formation of the Isthmus of Panama allowed North American fauna to invade South America in the Great American Interchange, including big cats, bears, elephants, camels, and horses. "Doedicurus" seems to have inhabited the relatively cold and humid Chaco-Pampean plains of northeastern Patagonia. It may have been the latest-surviving glyptodont, with remains suggested to date to 8,000–7,000 years ago during the middle Holocene, though these dates have been questioned. It may have gone extinct due to some combination of human hunting and climate change.