When the sons of Borr were walking along the sea-strand, they found two trees, and took up the trees and shaped men of them: the first gave them spirit and life; the second, wit and feeling; the third, form, speech, hearing, and sight. They gave them clothing and names: the male was called Askr, and the female Embla, and of them was mankind begotten, which received a dwelling-place under Midgard.
(Snorri Sturlson, The Prose Edda, Gylfaginning VII)
Why tree trunks, I wonder? Why not icicles or sand dunes? Isn’t it fascinating to wonder who made such stories up, and why? Presumably the original inventors of all these myths knew they were fiction at the moment they made them up. Or do you think many different people came up with the different parts of the stories, at different times and different places, and other people put them together, perhaps changing some of them without realizing that the various bits were originally just made up?
The very interesting work of David Lewis-Williams in The Mind in the Cave (2002) and Inside the Neolithic Mind (2005, with David Pearce) provide a plausible, evolutionary explanation that requires no con artists, liars, or frauds to explain the origins of myth. Mythic tropes emerged from the experiences of early shamans during altered states of consciousness, brought about by trance or drugs, in which the shaman believed he had visited a supernatural realm and encountered the gods. This realm is actually a product of the evolved neural pathways of the brain and accessible during altered states of consciousness. From these voyages, the shamans developed the kernels of stories about the origin of all things that persisted through time, accumulating gradual changes like in a game of Chinese telephone, where the story evolves without any one actor thinking he or she was responsible for a given change.
In other words, we would all benefit from taking Dawkins's own advice in The Magic of Reality and avoid “presuming” anything about the past, since presumptions only reflect back on us our own assumptions and biases.