Prehistoric times:
- 2.5-1.8 million years ago: The discovery of the use of fire and the sharing of the benefits of the use of fire may have created a sense of sharing as a group. Earliest estimate for invention of cooking, by phylogenetic analysis.[1]
- 2 to 5 million years ago: Hominids shift away from the consumption of nuts and berries to begin the consumption of meat.[2][3]
- 250,000 years ago: Hearths appear, accepted archeological estimate for invention of cooking.[4]