The Mayan Collaspe 1."...one strand consisted of population growth outstripping available resources..."
"Too many farmers grew too many crops on too much of the landscape."  Archaeologist David Webster (p. 176) 
2.     "Compounding the mismatch between population and resources was the second strand:  the effects of deforestation and hillside erosion, which caused a decrease in the amount of useable farmland at a time when more rather than less farmland was needed, and possibly exacerbated by an anthropogenic drought resulting from deforestation, by soil nutrient depletion and other soil problems, and by the struggle to prevent bracken ferns from overrunning the fields." p. 176 
3.       "The third strand consisted of increased fighting, as more and more people fought over fewer resources."  p. 176 
4.     "Bringing matters to a head was the strand of climate change."  p. 176 
5.     "..we have to wonder why the kings and nobles failed to recognize and solve these seemingly obvious problems undermining their society."  p. 177

The Mayans and the modern world 1. "Mayan environmental and population problems led to increasing warfare and civil strife." (p. 177) 2. "Maya peak population numbers were followed swiftly by political and social collapse." (p. 177) 3. "Copen's inhabitants also expanded from the floodplain to the more fragile hill slopes leaving them with a larger population to feed when the agricultural boom in the hills went bust." (p. 177) 4. "...Maya king's sought to outdo each other with more and more impressive temples, covered with thicker and thicker plaster-reminiscent in turn of the extravagant conspicuous consumption by modern American CEOs." (p. 177) 5. "The passivity of Easter chiefs and Maya kings in the face of the real big threats to their societies completes our list of disquieting parallels." (p. 177)

Modern World "Mayan environmental and population problems led to increasing warfare and civil strife.” Yes No

Modern World "Maya peak population numbers were followed swiftly by political and social collapse.” Yes No

Modern World "Copen's inhabitants also expanded from the floodplain to the more fragile hill slopes leaving them with a larger population to feed when the agricultural boom in the hills went bust." Yes No

Modern World "...Maya king's sought to outdo each other with more and more impressive temples, covered  with thicker and thicker plaster-reminiscent in turn of the extravagant conspicuous consumption by modern American CEOs." Yes No

Modern World "The passivity of Easter chiefs and Maya kings in the face of the real big threats to their societies completes our list of disquieting parallels." Yes No

Diamond’s highlights of the Maya collapse NEW WORLD'S MOST ADVANCED CIVILIZATION 1. "...sites of the New World's most advanced Native American civilization before European arrival, and the only one with extensive deciphered written texts." (p.157) Jared Diamond's thoughtful question "How could ancient peoples have supported urban societies in areas where few farmers make a living today?" (p. 157)

ENVIRONMENT NOT NOTABLY FRAGILE 2. "While their environment did present some problems associated with the karst terrain and unpredictably fluctuating rainfall, it does not rank as notably fragile by world standards..." (p. 159)
[Note to Reader: karst means a barren limestone region characterized by fissures, caves and underground channels.]

DIAMONDS'S SUMMARY OF MAYAN COLLAPSE FACTORS Professor Diamond's Own Summary of Major Factors Contributing to the Mayan Collapse:” “They did damage their environment, especially by deforestation and erosion.” (p. 159) “Climate changes (droughts) did contribute to the Maya collapse, probably repeatedly. ” (p.159) Hostilities among the Mayan themselves did play a large role." (p. 159)” ...political/cultural factions, especially the competition among kings and nobles that led to a chronic emphasis on war and erecting monuments rather than on solving underlying problems, also contributed." (p. 160)

RAINFALL UNPREDICTABLE 4. The climate varied markedly during the year:  dry season "seasonal desert" from January through April and wet season "seasonal tropical forest" from May to October. (p. 160)  Rainfall was unpredictably variable from year to year

RISK OF CROP FAILURE 5. ...they too must have faced risks of crop failures from droughts and hurricanes." (p. 160)

NO ANIMAL POWER 6. "...the Maya had no animal-powered transport or plows" (p. 165)

WARFARE WAS INTENSE "We now know that Mayan warfare was intense, chronic, and unresolvable, because limitations of food supply and transportation made it impossible for any Mayan principality to unite the whole region in an empire..." (p. 172) The archaeological record shows that wars became more intense and frequent towards the time of the classic collapse (A.D. 760-910).

REPEATED DROUGHTS 9. "The other phenomenon important to understanding Maya collapses is the repeated occurrence of droughts..." (p. 173)

CAUSES OF DEATH IN THE CLASSIC COLLAPSE (A.D. 760-910) "...some of the Maya population decrease surely involved people dying of starvation or thirst, or killing each other in struggles over increasingly scarce resources." (p. 175) The other part of the decrease may reflect a slower decrease in the birthrate or child survival rate over the course of many decades.  That is, depopulation probably involved both a higher death rate and a lower birthrate." (p. 175)