Now, it will depend on what part of the world you are looking at, and just how many of the cereals are lost. If Rice or Maize/Corn are spared, then civilizations as we know them are still possible, perhaps more restricted in their ranges.
There are other possible plants to domesticate apart from grasses, but the timelines to do so would prevent them from stopping civilization collapse.
(Been reading Guns, Germs and Steel (Excellent book!) and the author asserts the availability of grains as one of the key instigators of civilization..) Go to Comment
Take a look how old the submission is - many of the ones I have been digging up precede the 100 word challenge and even the more verbose general submission by many years.
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