Despite building great temples and pyramids, the mesoamerican empires had not invented
the calendar
the wheel
the stonecutter
the suspension bridge

The book by john kenneth galbraith discussed the growing gap between the increasing private wealth in the u.s. and the stagnant condition of resources allocated to the public sector.

What changes did japanese militarists make when they came to power?

What was the most important consequence of the large-scale ecological changes in africa two hundred thousand years ago?