Ancient Places

At the end of the last Ice Age, 13,000 years ago, North America was not a frozen wasteland. Though it was cold, it was a dry, windy grassland with dense growths of flowering herbs and sedges. Herds of mammoths with shaggy skin and long curved tusks grazed the nutrient-rich plants, accompanied by ancient bison and mastodons. Ecologists have described the mammoth steppe as one of the most productive large-herbivore ecosystems in Earth's history. Predators such as dire wolves and American lions hunted calves or weakened adults. A healthy adult mammoth had few natural enemies. Their enormous size, long curved tusks, and social behavior made healthy adults extremely difficult to kill. When humans arrived near the end of the Ice Age