The first people (or only the first men or the first women) are not created but come to earth from the underworld (from a cave) or from a small enclosure under the earth or on its surface (tree trunk, rock, gourd, etc.). Many people of both sexes and of different ages or people and different species of animals come out together
Reptiles or invertebrates possess the medicine of immortality; are contrasted with men as immortal with mortals and/or are responsible for originating of death; or a snake's bite inflicts the first death
Death (also Old Age, Disease, etc.) is a particular person not identical with the Master of the Dead. He kills people usually carrying away their souls
Giant reptilian monster (serpent, more rare fish, chain of fish) extends in the sky and/or supports the sky being associated with Milky Way or the rainbow