Another possibility is that consciousness evolved even earlier in animal history and is even more widely distributed among animals, and hence has a function that is even more fundamental to animal life. Ginsburg &amp; Jablonka (2007a,b) attribute a primitive form of “overall sensation” as a by-product of even the simplest nerve nets in animals. They argue that as these states became harnessed to learning and motivation that they acquired the functional properties of “basic consciousness”.  If this is right, than consciousness may have arisen not independently in arthropods, mollusks and vertebrates, but only once in the common ancestor of these ancient groups, very early in animal evolution. 