The extension of care to others seems to have emerged after the development of agriculture roughly ten thousand years ago.

Fortunato and Archetti note that monogamy emerged in Eurasia as agriculture became widespread, with land and herds as an important source of wealth that could be passed to heirs. 

Robert Boyd and Peter Richerson argue, in humans, the extension of cooperation beyond kin and known tribal members was likely common only after the advent of agriculture, about 10,000 years ago. 

​

- Patricia Churchland

Braintrust