Just after 4,200 years ago there was a negative shift in the North Atlantic Oscillation, which began drying the wheat fields in Mesopotamia. The Akkadian Empire moved in to take advantage of the hunger and unrest, and then the Akkadians disappeared from history for the same reason. Agriculture was wrecked in the Indus Valley, and there world-wide social collapses, migrations, refugees, and ineffective walls were built. A global climate disruption occurred as rain belts shifted north again, setting up millennia of warmth and drought. It was a bad time to be living in a complex society based drought-stressed agriculture. In Texas, however, the new climate regimen, the Edwards Interval (4,200 – 2,800 BP) was a time of more rain, even though the rainy times were punctuated by dry episodes. As it started to rain again, the grasses thickened and then died and burned back during drought. The resulting void after each drought was quickly filled with a sequence of buffalograss, hairy grama, then side-oats grama, before returning to little bluestem equilibrium. Natives in the 17th century were seen expediting this cycle by setting fires among the post oaks to remove brush and other vegetation. These fires created a more open post oak savannah more inviting to the returning bison. The resident hot-rock-bakers must have benefitted from the return of more mesic conditions and the more regular appearance of the bison herds. The Southern plains buffalo range spread into Texas, through the Western Cross Timbers and all the way to the coast. Perhaps, as the early Spanish observed, the bison remained all year in the wooded environment. A French traveler noted that there were prairie patches in the Cross Timbers with small bison herds in each one. A new people arrived in the rich grasslands, these were the Pedernales point-users whose dart heads are among the most commonly found in Erath County. Unlike the earlier narrow point styles, the Pedernales were barbed and with broader blades – characteristics associated with buffalo-hunting points. Dan Young, Unpublished Manuscript, 2022