El Fin del Mundo — Henry Wallace
Paleoindian research encompasses a number of broad questions of far-reaching significance. Who were the first peoples to reach the Americas? When did they arrive? What was the relationship between the makers of Clovis spear points and the extinction of megafauna, such as the horse, mammoth, dire wolf, and other animals? Although these issues have long been debated, no consensus has been achieved. Big questions can persist because of in- sufficient evidence or because re- searchers have not adequately or fully interpreted the available infor- mation. A few researchers have pro- posed dramatically new ideas— such as the possibility of a comet col- liding with the earth (page 18)— and others, like Joe Cramer, have decided that these questions will be resolved only by supporting many more researchers who will generate new data. Both approaches are ex- amined in this issue of Archaeology Southwest…
“The end of the last Ice Age in North America was a time of enormous change: mile-thick glaciers were retreating rapidly, the sea level was rising, and large mammals, such as mammoths, ground sloths, camels and dire wolves would soon disappear.” Although a convergence of climate change and Paleo-Indian hunters may be a cause of the great extinction, “researchers still do not know exactly what happened.”
My own vulgate opinion is not much better informed than the average American science buff – excepting the portion of that opinion formed during the comparatively brief time I lived in the Navajo Nation plus day-to-day experience working construction trades in northern New Mexico, sometimes within one or another Rio Grande or Northern Pueblo.
I agree with that school of thought that presumes Paleoindian hunters to be the primary cause of the great extinction of large mammals from North America. Not unusual when and where human beings are part of the equation. Regardless – RTFA. It is a lovely, in-depth examination of many of the questions of the Paleoindian period in North American history.
Eideard 
Climate problems alone were not enough to end periods of ancient Pueblo development in the southwestern United States. https://www.eurekalert.org/pub_releases/2021-04/wsu-stp042121.php
Drought is often blamed for the periodic disruptions of these Pueblo societies, but in a study with potential implications for the modern world, archaeologists have found evidence that slowly accumulating social tension likely played a substantial role in three dramatic upheavals in Pueblo development.
The findings, detailed in an article in the Proceedings of the National Academy of Sciences, showed that Pueblo farmers often persevered through droughts, but when social tensions were increasing, even modest droughts could spell the end of an era of development.
“Societies that are cohesive can often find ways to overcome climate challenges,” said Tim Kohler, a Washington State University archeologist and corresponding author on the study. “But societies that are riven by internal social dynamics of any sort – which could be wealth differences, racial disparities or other divisions – are fragile because of those factors. Then climate challenges can easily become very serious.”
During the Bronze Age, Mesopotamia was witness to several climate crises. In the long run, these crises prompted the development of stable forms of State and therefore elicited cooperation between political elites and non-elites. This is the main finding of a study published in the journal PNAS and authored by two scholars from the University of Bologna (Italy) and Eberhard Karls Universität Tübingen (Germany). https://www.eurekalert.org/pub_releases/2021-04/udb-cci042721.php