What Was The Cause For The Fall Of The Mayas?

The Mayas slipped on a banana skin leading to the fall

Archeologists used to argue about whether the downfall of the Maya was due to drought or warfare or disease, or a number of other possibilities such as political instability. Now it is believed that all these things played a role, but that they were only symptoms. The root cause was a chronic food and water shortage, due to some combination of natural drought and deforestation by humans.