Defining the Central Mountains Archaic : Great Basin natural and cultural biographies : the archaeology of Monitor Valley, contribution 5
Authors: Thomas David Hurst , Canaday Timothy W. , Layton Thomas N. , Millar Constance I. , Pendleton Lorann S. A. , Robinson Erick , Rogers Alexander K. , Semon Anna M. 
Published: November 2024

This second volume of the Alta Toquima trilogy situates Monitor Valley archaeology within the Central Mountains Archaic, introduced here as a taxonomic equivalent to the better-known Lovelock culture, Fremont complex, and the Virgin Branch of Ancestral Puebloans. This analysis integrates Monitor Valley into the broader Intermountain West using seven multiscalar time slices that address paleoclimatic and cultural change from the Late Pleistocene/Early Holocene (pre-7000 cal b.c.) through the Little Ice Age (cal a.d. 1350–1800). This overview establishes that the loglinear relationships between two independent cultural proxies (nearly 5000 cultural radiocarbon dates and more than 47,000 time-sensitive projectile points) are highly correlated (r = 0.988) and relevant for explicating region-by-region demographic change. We hypothesize that the Intermountain West achieved (or exceeded) exponential growth throughout more than 90% of the 13 millennia spanning Paleoindian colonization through Euro-American contact. During two notable exceptions—the Late Holocene Dry Period (850 cal b.c.–cal a.d. 100) and the late 13th-century drought—human population growth fell below exponential expectations. The Late Holocene Dry Period (LHDP) was a pivotal climatic event that varied in geographic range, duration, and intensity. The 42°–40° N dipole hypothesis holds that persistent La Niña-like climatic conditions resulted in an anomalously moist northern Great Basin and exceptionally arid southwestern Great Basin, separated by an undulating dipole transition between 42° and 40° north latitude. Human demography plummeted below exponential expectations as foragers abandoned almost all settlements south of the 42°–40° N dipole, marking an intensification that shifted away from “man caves” and logistical bighorn hunting to extended family bands who created the first alpine residences at Alta Toquima. The high-elevation settlements were occupied only during the driest of the short-term xeric-mesic cycles during (and after) the LHDP. In wetter times, the alpine houses were abandoned in favor of repurposed man caves and other subalpine base camps. These syncopated intensifications began a full millennium before the arrival of bow technology into the Central Mountains Archaic. The other exception to exponential growth was the tumultuous late 13th-century drought, when the Fremont complex dissolved after a dozen centuries of farming, the Lovelock culture disappeared, and the Virgin Branch of Ancestral Puebloans collapsed—all part of the far-reaching demographic decline in the American Southwest and elsewhere across interior North America. In the aftermath of these fundamental economic shifts, changing social landscapes, and human migrations, the Little Ice Age returned to exponential growth during the challenges and windfalls for Shoshonean communities of the Intermountain West. This volume proposes and tests multiple hypotheses addressing the deep natural and cultural histories of the Intermountain West. Resilience theory proves to be an important tool in unraveling relationships between abrupt climatic and behavioral adjustments, human paleogeography, piñon pine processing, multiple meanings of abandonment, adaptation to lacustrine and desert-mountain mosaics, and shifting landscapes of ritualized practice.