Introduction
Current dramatic breakthroughs in archaeological science provide persuasive new insights about the collapse of past civilizations. Winston Churchill once remarked “The longer you can look back, the farther you can look forward.” Armed with DNA analysis of the movements of human populations, animals, and pathogens; strontium isotope analysis documenting the movements of people over the course of individual lifetimes; analyses of past climates through beryllium as well as oxygen isotope analysis, together with the drilling of deep lake, sea, glacier, and cove cores, and the study of annual growth of tree rings, among other scientific advances, we can look back upon the history of humankind as never before. Five causes of collapse appear paramount: major episodes of climate change, crises-induced mass migrations, pandemics, dramatic advances in methods of warfare and transport, and human failings in crises including societal lack of resilience and the madness, incompetence, cultic focus, or ignorance of rulers.
Wiener, Malcolm. “The Collapse of Civilizations.” Belfer Center for Science and International Affairs, Harvard Kennedy School, September 2018