Cannibalism has always fascinated mankind, not in small part because of the mystery that hangs over the unanswerable question. Why would one eat a fellow human being? Is there a time when such a thing was normal? What does human flesh taste like?

Now, researchers found evidence of cannibalism having been practiced by ancient humans in Spain 10,000 years ago. According to a report from the Daily Mail, around 30 human bones were found in the Santa Maira caves in Spain that had signs of being the victims of cannibalism.

The remains are around 9,000 to 10,000 years old and marred by strange markings that are caused by human teeth, stone tools and fire. Animal remains were also discovered in the site with the same markings.

In the collection of over two dozen human bones, the archaeologists were able to pick out three separate cranial remains of an infant, a slender adult and a larger adult.

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Archaeologists can distinguish marks from human teeth due to the distinct clues it leaves behind as opposed to other predators: double arch punctures, isolated triangular pits and shallow linear marks. These markings match the ones found in typical prey of the Mesolithic hunters such as ibex, red deer, wild boar, fox and rabbit.

The researchers ran the evidence against a set of characteristics that's used to diagnose cannibalism. According to a report from Science Alert, these different criteria are: direct proof of human bones in fossilized human feces; indirect proof of cooking marks; first-order primary criteria; second-order primary criteria; and secondary criteria indirectly related to functional exploitation.

These remains from Spain meet all the criteria except for finding remains in human waste.

However, it's not clear whether this group of people ate other humans due to scarcity of food or as part of their ancient rituals for funerals or other practices.

The study was published in the Journal of Anthropological Archaeology.

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