Asia
The coastal periphery was home to some of the world's earliest known civilizations, each of them developing around fertile river valleys. The civilizations in Mesopotamia, the Indus Valley and the Yellow River shared many similarities. These civilizations may well have exchanged technologies and ideas such as mathematics and the wheel. Other innovations, such as writing, seem to have been developed individually in each area. Cities, states and empires developed in these lowlands.
History of the Americas
The Olmec civilization was the first Mesoamerican civilization, beginning around 1600-1400 BC and ending around 400 BC. Mesoamerica is considered one of the six sites around the globe in which civilization developed independently and indigenously. This civilization is considered the mother culture of the Mesoamerican civilizations. The Mesoamerican calendar, numeral system, writing, and much of the Mesoamerican pantheon seem to have begun with the Olmec.