The invention of agriculture was probably the most important change in human history but scholars argue about why it happened, and propose three main conflicting theories.
These theories, and the difficulties in domesticating plants and animals are the subjects of lectures 14 and 15 in UCSD anthropologist Tara Carter’s great course, Prehistory and the Birth of Civilization (audio).
Carter clearly loves her subject and radiates infectious enthusiasm. Although these lectures are in audio format, her sprightly, happy voice makes me feel like she is smiling, and I have the urge to smile back.
Here are the main theories that Carter discusses:
Shortage model: In this theory, climate change causes a shortage of food. At the end of the ice age, when the climate dries, people congregate in oases where food is available. As the oases become crowded, some smart people innovate, and voila, you have farming.
Abundance model: In this model, agriculture grows out of an abundance of food. There is so much food around, people accidentally start domesticating crops and animals.
Competition model: This model supposes that people developed agriculture because they liked to drink alcoholic beverages. (All of the early domesticated crops could be fermented.) This theory proposes that particularly ambitious people worked at producing extra grain so they could have alcoholic beverages to trade.
You’ll have to listen to the lectures to get the whole scoop, but I can give away a bit of the ending. Carter does not buy any of these theories in their entirety, but thinks that each makes an important contribution in our understanding of the agricultural revolution.