In researching for my book project, a history of the Bosque River, I ran across a megadrought. Paleoclimatoligists are still trying to find out what caused this event: Centered around 4,200 years ago, the Indus Valley Civilization collapsed, Egypt’s Old Kingdom fell, the Liangzhu culture in China disappeared, and the Akkadian Empire in Mesopotamia was gone in only fifty years. These calamities all occurred in the Northern Hemisphere at the same latitude. It just stopped raining for a century or more in huge areas along the middle latitude, and became more rainy in some places. In North America, the drought centered in the mid-continent, exempting Central Texas. In 2018, the International Union of Geological Sciences, determined that this event would mark the beginning of the current stage of the Holocene, they named it the Meghalayan Age. And in Texas, the Late Archaic begins at the same time 4,200 years ago, not because the ecology was wrecked, but because of the refugees that moved in from the drought-stricken areas in the north and northeast. The Late Archaic occupation sites along the Bosque River show intense use and increased populations. There are more dart point types (darts were about five feet long and launched with a throwing stick, this is before bows) and the suggestion of competition and conflict.