The male and the female birds bring with them different kinds of precipitations (e.g. the male comes with a hail, the female with a rain). Or (Buryats of Mongolia) one and the same bird brings different kinds of precipitations depending on is it angry or not.

Anthropomorphic beings have no mouths

Human teeth are made of material subject to easy damage (etiology of tooth ache in most cases)

Dog is responsible for people being mortal or imperfect. Usually the antagonist bribes dog with a warm fur and the dog lets him spoil the half-ready human figures

A turtle, toad, or frog supports the earth (sky) or is its embodiment

Person gives a trickster his power (usually skunk gives his charge) but he squanders it all to see the effect. When a real need comes, the device does not work anymore

Snow was edible or something edible was falling from the sky instead of the snow

Baskets carried loads by themselves

A small girl or boy who is a child of a deity comes to live with humans. Thanks to that, food or other resources become easily available. The child is maltreated, returns to its own world, human life becomes difficult and scanty

Rivers were flowing or according to the original plan had to flow in both directions; somewhere there is a river that flows in both directions