|Millennia:|| ||6th millennium BC -||5th millennium BC -||4th millennium BC|
The 5th millennium BC sees the spread of agriculture from the Middle East throughout southern and central Europe. Urban cultures in Mesopotamia and Anatolia flourish, developing the wheel. Copper ornaments become more common, marking the Chalcolithic. Animal husbandry spreads throughout Eurasia, reaching what is now modern day China. World population grows slightly throughout the millennium, maybe from 5 to 7 million people.