13,000 BC. These first peoples are referred to as Clovis hunters, named after one of the first excavated archeological sites near Clovis New Mexico. By 12000 BC the Clovis hunters had migrated east to what is now Edmonton and south to New Mexico. First Nations history can be separated into three basic time periods: archaic or pre-woodland (1200 BC and earlier), woodland or pre-contact (1200 - 1600), and post-contact. North America at that time was teeming with game, not just buffalo, deer, antelope and bear, but elephants, lions, cheetahs, wild horses and even, further south, camels and giant ground sloths. Within 1000 years most of the very large mammals were extinct. It is generally assumed that the influx of man was responsible for this. By 11000 BC, Clovis hunters had developed many social centers across North America spreading to the east as the Canadian ice cap receded. There is evidence that the native peoples had domesticated such plants as sunflower and goosefoot, but there is no evidence that they domesticated any animals. Food production, as we know it, began with the invasion of the Europeans in around 1500 AD. Food cultivation and management, on the other hand, was a well developed skill for most early North Americans. They knew where food grew and how to encourage growth, but they did not concern themselves with ownership of land or monopolizing certain areas because of their food yield. As Jared Diamond points out in his work on global human development, Guns, Germs