A Newly Identified Younger Dryas Component in Eagle Cave, Texas

Recent excavations by the Ancient Southwest Texas Project of Texas State University sampled a previously undocumented Younger Dryas component from Eagle Cave in the Lower Pecos Canyonlands of Texas. This stratified assemblage consists of bison (Bison antiquus) bones in association with lithic artifacts and a hearth. Bayesian modeling yields an age of 12,660–12,480 cal BP, and analyses indicate behaviors associated with the processing of a juvenile bison and the manufacture and maintenance of lithic tools. This article presents spatial, faunal, macrobotanical, chronometric, geoarchaeological, and lithic analyses relating to the Younger Dryas component within Eagle Cave. The identification of the Younger Dryas occupation in Eagle Cave should encourage archaeologists to revisit previously excavated rockshelter sites in the Lower Pecos and beyond to evaluate deposits for unrecognized, older occupations.

A combined mesowear analysis of Mexican Bison antiquus shows a generalist diet with geographical variation

Bison antiquus Leidy, 1852 was one of the largest and most widely distributed megafaunal species during the Late Pleistocene in North America, giving rise to the modern plains bison in the middle Holocene. Despite the importance of the ancient bison, little is known about its feeding ecology. We employed a combination of extended mesowear, and mesowear III to infer the dietary preference and habitat use of three Mexican samples of B. antiquus. These included two northern samples—La Piedad-Santa Ana and La Cinta-Portalitos—from the Transmexican Volcanic Belt morphotectonic Province, as well as one southern sample—Viko Vijin—from the Sierra Madre del Sur morphotectonic province. We found that the northern Mexican samples were primarily nonstrict grazers, whereas the southern sample displays a pattern consistent with mixed feeding habits. This suggests variability among the diets of the bison from these samples, caused by different paleoenvironments. This evidence complements the paleoenvironmental reconstructions in the studied localities; for the northern samples, open prairies composed of patches of woodland or shrubland and, for the southern locality, a fluvial floodplain with short-lived vegetation. In both scenarios, grasses (Poaceae) were nondominant. The dietary habits of our samples of ancient bison in Mexico are the southernmost dietary inference for the species in North America and expand our knowledge of the dietary habits of B. antiquus during the Late Pleistocene.

Jake Bluff: Clovis Bison Hunting on the Southern Plains of North America

Clovis hunters of the North American Great Plains are known for their ability to hunt and scavenge mammoths. Less is known of their hunting strategies for other large animals, such as horse, camel, and bison, although remains of these animals have been found at several Clovis camps. Recent investigations of the Jake Bluff site on the southern Plains have identified a Clovis bison kill in an arroyo. The apparent use of an arroyo style trap for bison hunting provides the opportunity to study Clovis hunting strategies that came to be widely used during later Paleoindian times. The arroyo style bison trap is generally attributed to Folsom and later groups, and yet the Jake Bluff site yielded an association of Clovis-style projectile points with the remains of 22 Bison antiquus at the bottom of a short arroyo. The late date of 12,838 cal. BP suggests that the site spans the gap between the Clovis mammoth hunter and the Folsom bison hunter, indicating that some Clovis hunters developed the arroyo style bison trap to capture multiple bison at the same time, and as mammoths were extirpated from certain areas during the Pleistocene to Holocene transition.

Late Pleistocene northward-dispersing Bison antiquus from the Bighill Creek Formation, Gallelli Gravel Pit, Alberta, Canada, and the fate of Bison occidentalis

Late Pleistocene bison skeletal remains from the Gallelli Gravel Pit in the Bighill Creek Formation at Calgary, Alberta, document at least two individuals, including the largest postglacial bison reported from North America south of Beringia. Two partial crania, dated to 11 290 and 10 100 14C years BP, are referred to the southern species Bison antiquus Leidy, indicating northward movement from the midcontinent as ice retreat opened a corridor between Laurentide and Cordilleran ice. Their large size suggests a dispersal phenotype exploiting newly available territory. DNA evidence links the 11 290-year-old bison to Clade 1, which includes modern B. bison . This supports in situ evolution of B. bison from B. antiquus through the intermediate usually called B.“occidentalis” . Bison of B. “occidentalis” character appeared in Alberta about 10 ka BP, and the DNA evidence counters the suggestion of a migratory wave from Beringia. The B. occidentalis type specimen is from Alaska, so this name may be inappropriate for southern populations. Radiocarbon dates suggest that the Bighill Creek Formation paleofauna comprises two faunules separated in time by the Younger Dryas climatic episode.