Any of several mythical ancestral beings of the Marind-Anim people of southern New Guinea.
In their mythology, the killing of a divine ancestor (a dema deity) brings about the transition from the ancestral world to the human one. In Ceramese mythology, for example, the goddess Hainuwele grows from a coconut blossom and is dismembered by dema men; when the pieces of her body are buried, they become new plant species, especially tubers, the chief food of the Ceramese. Such myths offer explanations for the origin of agriculture as well as for human sexuality and death.