Autocracy wasn’t inevitable in early civilizations — many were more egalitarian. But when riches were there to monopolize, strongmen and inequalities emerged.

Mutualistic partnerships between species abound across nature — but it’s a tricky dance to make sure both parties keep pulling their weight

There’s an urgent need to study how artificial intelligence makes ethical choices because it soon will make many such decisions in our stead, says computer scientist Iyad Rahwan