In a graveyard in Al-Kadada, north of Khartoum, the archaeologists have dug up the tomb of a man and a woman facing each other in a ditch, with bodies of two women, two goats and a dog buried nearby.
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The ancient unearthed bones date from between 3,700 and 3,400 BC, a period considered as one the key stages in the transition from a hunting to a farming society.
Presumably, the ritualistic character points to sacrifice, but we might need more instances if the same ritual to be quite sure.