Freshwater availability as the constraining factor in the Middle Paleoindian occupation of North‐Central Florida

Abstract

The locations of reliable surface water exposures during the Middle Paleoindian period (10,200 14 C yr B.P.) in north-central Florida are reconstructed and compared to the concentrations of Middle Paleoindian projectile points. Estimates of water table levels and surface water flow in Florida's karst geology confirm prior climate reconstructions for that time indicating the area was arid and supported a xeric ecology in most upland locales. Surface water flow data from recent extreme droughts and water table estimations are used to identify the areas of highest probability for surface water availability. The distribution of the highest concentrations of Middle Paleoindian points correlates with the areas of highest probability, indicating that scarce surface water sources were the strongest constraint on occupation location during that time.

Geoarchaeological investigations at the Ryan‐Harley Paleoindian site, Florida (8JE1004): Implications for human settlement of the Wacissa River Basin during the Younger Dryas

“…During the hypothesized Suwannee time frame, sea level was far lower than at present, ranging from ~70 meters below sea‐level (mbsl) at 12,900 to ~60 mbsl at 11,700 calbp (Joy, 2019). Lower sea‐level equates to a reduction in the potentiometric surface of the Upper Floridan Aquifer, and overall arid conditions indicate that hydrostatic head would have been insufficient to maintain year‐round flow (Perrotti, 2017; Thulman, 2009). Thus, the Wacissa River may not have flowed on a consistent, annual basis during the Late Pleistocene.…”

“…At the onset of MIS 2 (~29–14 kya), sea‐level fell to ~90 m lower than at present, exposing a landmass twice the size of present‐day Florida (Joy, 2019; Lambeck et al, 2002). Cold and dry conditions dominated the region, and the landscape overall lacked widespread freshwater (Grimm et al, 2006; Grimm, Jacobson, Watts, Hansen, & Maasch, 1993; Perrotti, 2017; Thulman, 2009). Much of Florida instead resembled an open, sandy savannah with occasional vegetated sand sheets in low‐lying basins and sporadic hardwood forests in upland areas (Erlandson et al, 2011; Grimm et al, 1993; Watts, 1969; Watts, 1975; Watts, 1983; Watts, Hansen, & Grimm, 1992).…”

“…This restricted geographic range is a trend observed in other post‐Clovis (~13,100–12,700 calbp) groups in the Southeast (Waters & Stafford, 2007), such as Cumberland and Quad (Anderson, Smallwood, & Miller, 2015). The relative chronology and regional distribution of Suwannee points has led to the general consensus that Suwannee point makers lived during the Younger Dryas (~12,900–11,700 calbp; Anderson et al, 2015; Dunbar, 2016; Thulman, 2009).…”

Regional variation in the terminal Pleistocene and early Holocene radiocarbon record of eastern North America

“…This argument has been subsequently appropriated by those arguing for an extraterrestrial impact as supporting evidence (Firestone et al, 2007). It should be noted, however, that there are many researchers in the eastern United States who argue for some Younger Dryas effect, yet do not invoke a cosmic catastrophe (Anderson and Faught, 2000;Anderson, 2001;Anderson et al, 2004;Dunbar and Vojnovski, 2007;Faught, 2008;Thulman, 2009;Ellis et al, 2011). Holliday and Meltzer (2010) have also questioned whether there is enough evidence available to suggest that climate change during the Younger Dryas chronozone happened on a scale perceptible to humans.…”

“…Archeologists have become increasingly interested in the time period coinciding with the Younger Dryas chronozone (~12,900-11,600 cal yr BP) and the role of climate change in shaping the prehistory of North America. Specifically, some cite the onset of the Younger Dryas as a factor in the demise of megafauna populations and a possible cause of a demographic collapse or reorganization of human populations (Fiedel, 1999;Anderson and Faught, 2000;Anderson, 2001;Lovvorn et al, 2001;Anderson et al, 2004;Hall et al, 2004;Dansie and Jerrems, 2005;Haynes, 2005Haynes, , 2008Newby et al, 2005;Dunbar and Vojnovski, 2007;Faught, 2008;Thulman, 2009). An extra-terrestrial impact event has also been offered as one explanation for the downfall of these populations (e.g., Firestone et al, 2007).…”