Strauss and colleagues investigated 26 human burials. They were surprised by the diversity and complexity of the remains in a region of South America where hunter-gatherer communities were assumed to be extremely simple and homogeneous.
"The burials included bones with cutting and chopping marks, exposure to fire, a head buried with amputated hands and skulls in which all teeth were intentionally removed," Strauss told Discovery News.
"In one case a skull cap was used as funerary receptacle. The mutilated and burnt bones of the same individual were deposited inside," Strauss added.
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The researchers also noted that some chopped and defleshed bones show gnaw marks and signs of burning soft tissues, pointing to some form of ritual cannibalism.
Analysis of the remains showed that the practice of mutilation, followed by the secondary burial of the remains according to strict rules, was a central element in the treatment of the dead.
Then, between 8,200 and 8,600 years ago, another change occurred. Pits were filled with bones of a single individual without signs of body manipulation.
"This finding testifies that a great cultural diversity was already present in South America already 10,000 years ago," Strauss said.
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