A Anew thought
B Different songs
C A comfortable life
D Happy memories
Ancient Egypt Brought Down by Famine
Even ancient Egypts mighty pyramid builders were powerless in the face of the famine that helped bring down their civilization around 2180 BC. Now evidence collected from mud deposited by the River Nile suggests that a shift in climate thousands 0fkilometers to the south was ultimately to blame--and the same or worse could happen today.
The ancient Egyptians depended on the Niles annual floods to irrigate their crops. But any change in climate that pushed the African monsoons southwards out of Ethiopia would have reduced these floods.
Declining rains in the Ethiopian highlands would have meant fewer plants; to stabilize the soil. When rain did fall it would have washed large amounts of soil into the Blue Nile and into Egypt, along with sediment from the White Nile.
Blue Nile mud has a different isotope signature from that of the White Nile. So by analyzing isotope differences in mud deposited in the Nile Delta, Michael Krom of Leeds University worked out what proportion of sediment came from each branch of the river.
Krom reasons that during periods of drought, the amount of Blue Nile mud in the river would be relatively high. He found that one of these periods, from 4500 to 4200 years ago, immediately came before the fall of the Egypts Old Kingdom.
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