Chronology American cookery begins not in kitchens as we know them today, but around open campfires, in the mouths of caves, and in huts. Hunting implements such as spears and knives made from stone are the technologies that the first migrants into the Amer i cas used to capture, gather, and prepare foods. Over the course of centuries, Native Americans exploited local food sources, developed agriculture, invented pottery for food storage and cooking, and created local cuisines. Euro pean and African immigrants after 1500 CE brought new plants and animals to the Americas along with new food production and preparation technologies. These were developed over the next 500 years to become the modern industrialized food systems and dishes that Americans know and use each day. 20,000–18,000 BCE The first Americans, small groups of hunter-food collectors, begin to migrate from a homeland in Beringia, a landmass linking Asia to Alaska, sometime after 22,000 years ago. They travel down the continent by boat and on foot reaching Chile by at least 16,000 BCE. 10,000 BCE Later migrations of hunter-gatherers bring Na-Dené-speaking peoples and Aleut- Eskimo speakers as late as 4000–2000 BCE. The southern group of Na-Dené speak- ers include Navajos of the American Southwest. 10,000–8000 BCE Paleo-Indians, as they are commonly known, find late Ice Age animals such as woolly mammoths, mastodons, giant sloths, and giant beavers. These are widely hunted and at the end of the Ice Age all but bison have disappeared. 9000–8000 BCE As ice sheets disappear, the North American landforms and biomes that exist more or less today are formed. Native American peoples fill every ecological zone, hunt- ing large and small game and gathering numerous wild plants for food.