Sumerian signs for sheep and goats with male to female correspondence.

Signs taken from Archaic Bookkeeping by Hans J. Nissen, Peter Damerow, Robert K.Englund, and translated by Paul Larsen; page 89.

Organization of top graphic by Jennifer Ball © April 29, 2011.

Who knew Sumerians were electricians? These depictions seem to indicate the parts of animals that “plug” together, probably because that’s how you make more animals. The darker sign on the left is the Sumerian equivalent of the definition on right. The grayed-out sign next to it is the complementary sex partner of the animal on the left (ram to ewe, male lamb to female lamb, etc.). These signs depict the bottoms—the genitalia—of animals in a symbolic way.