Early food producing societies used megaliths big

Early food-producing societies used megaliths (big stones) to construct
burial chambers and calendar circles and to aid in astronomical
observations.
00. The expansion of food-producing societies may be reflected in the
patterns in which the Indo-European, Sino-Tibetan, and Afro-Asiatic
language groups are dispersed around the Eastern Hemisphere.

IV0. Mesopotamia
0. Settled Agriculture in an Unstable Landscape
00. Mesopotamia is the alluvial plain area alongside and between the
Tigris and Euphrates Rivers. The area is a difficult environment for
agriculture because there is little rainfall, the rivers flood at the wrong
time for grain agriculture, and the rivers change course unpredictably.
00. Mesopotamia does have a warm climate and good soil. By 4000
B
.
C
.
E
.,
farmers were using cattle-pulled plows and a sort of planter to
cultivate barley. Just after 3000
B
.
C
.
E
., they began constructing
irrigation canals to bring water to fields farther away from the rivers.
00. Other crops and natural resources of the area included date palms,
vegetables, reeds and fish, and fallow land for grazing goats and
sheep. Draft animals included cattle and donkeys and, later (second
millennium
B
.
C
.
E
.), camels and horses. The area has no significant
wood, stone, or metal resources. Mesopotamia had an abundance of
mud.