Ecclesiastes 3:20

"All go to the same place. All came from dust and all return to the dust."

The same place isn't the afterlife (Ecclesiastes 12:7), but rather the grave or the soil. The bodies of animals and man both decay and eventually return to the dust. "showing us man on his journey from dust to dust, as in Genesis 3:19, confronts us with the Fall, and with the irony that we die like cattle because we fancied ourselves as gods" (Kidner p. 42). Once men start moving in the direction of evil, they will become more and more like animals (2 Peter 2:12 "as creatures with reason"). How many people have you encountered who in order to hold on to their sins have abandoned their intellectual honestly? Man, apart from God, in all his pomp, is just like an animal (Psalms 49:12)