1. The Uruguain tradition – this culture produced bifacial stemmed projectile points from stone. This means that implements had two flaked sides, a stem on which to hold, sharpened edges and a pointed tip. This was then used as a knife, pick, scraper or weapon. This type of implement was ideal for the open vegetation of the area in which these tribes lived.
Many anthropologists and archaeologists believe that the remains of civilisations found dating to about 8 000 years ago belong to a group of people that undertook a mass migration from Asia, having to cross either or both the Pacific Ocean and the Bering Strait. When the Portuguese arrived millennia later, they referred to all of the indigenous people as ‘Indians’.
Then, about 7 000 years ago, two new traditions arose in response to the local inhabitants’ having to find new habitats and methods of living. These were:
1. The Humaitá tradition – these ones used bifacial tools that were significantly larger than before, and lacked the pointed tips. This group of people inhabited the broad-leaved forests.
3 000 years later, evidence indicates that there were civilisations that had settled along the shores of Rio de Janeiro and Espírito Santo and that were making use of domesticated or semi-domesticated plants. This means that these plants were 1) enjoyed for their aesthetic value, and not just for what they could produce as food or shelter (although this was, of course, a great advantage) and 2) under the care of human beings for multiple generations.
Although maize was a major crop and source of food, a hunter-gatherer way of life persisted. It has been very difficult to ascertain how and when exactly specific cultural traditions changed, but the changes in weather patterns and other environmental factors was certainly a major determining factor.
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