Self-study
Archaeologist: Support For 2,000 years the ancient Sumerians depended on irrigation to sustain the agriculture that fed their civilization. ███ ██████████ ██████████ █████ ██ ██ ███ ████ █████ ██████ ██ ███ █████ ███ █████ ██████████ ████ ██████ ████ █████ ███████████ ████ ███ ████ ██████ ██████ ██ ███████ ████████████ ████████ ████████████ ██████████ █ ███████ ████ ██ ████ ██████ ██ ██████ ██████ █████████████ ████ ████████ ██ ████ ███████ ██ ██████████ ███ ████████████
Summarize Argument
The author concludes that modern civilizations that continue to rely heavily on irrigation for agriculture are likely to collapse. This is based on a comparison to the ancient Sumerian civilization, which relied on irrigation for agriculture. After irrigation built up toxic levels of salts and other impurities in the soil, the Sumerian civilization collapsed.
Notable Assumptions
The author assumes that the problem of toxic levels of salts and other impurities faced by the Sumerians is likely to face modern civilizations that rely on irrigation for agriculture.
2.
Which one of the following, ██ █████ ████ ███████ ███ ███████████████ █████████
a
Most modern civilizations █████ ███ ████ ██████████ ███████ ███████████ ███████ ███████ ███████ ██ ███████████
This suggests modern civilizations need irrigation to feed themselves through agriculture. But this doesn’t relate to whether such reliance will lead to collapse from toxic soil.
b
Factors unrelated to ███ ███ ██ ██████████ █████ ████████ ████ ██████ ████████ ████████████ ██ ████████ ██████ ██ ██████
Even if other factors would have led to the Sumerian collapse, that doesn’t change the fact that toxic soils contributed to the Sumerian collapse or whether what happened to the Sumerians will happen to modern civilizations.
c
Many modern farmers ███ ██████████ ██████████ ████ █████ ███ ███████ ██ █████ ███ █████ █████ ██████████ ██ ███ █████
This points out why what happened to the Sumerians might not happen to modern civilziations. Modern techniques might not lead to toxic levels of salt and impurities in soil.
d
Many modern civilizations ██ ███ ████ ██ ███ ███████████ ██████ ██ ██████████ ███ ████████████
We’re concerned with what happens to the ones that do rely on irrigation for agriculture. But whether these kinds of civilization are common or rare doesn’t relate to whether these kinds, however many there are, will collapse.
e
The soil of ███████ ███████ ███████ █████████ ████ █████ █████ ███ █████ ██████████ ██████ ███ █████████ ███████ █████ ██████████ ███ ████████████
We have no reason to think modern soil doesn’t also contain some toxic salts and other impurities. In addition, even if modern soil doesn’t already have this, that just means it might take longer for the collapse. But (E) doesn’t suggest there wouldn’t be a collapse.