Dr. Kurt Rademaker co-authors article on precise manual activities in an Early Holocene individual of the Peruvian Andes

Department of Anthropology Assistant Professor Kurt Rademaker recently co-authored an article in the American Journal of Physical Anthropology with members of his research team, including first author Dr. Fotios Alexandros Karakostis and Dr. Katerina Harvati of the University of Tübingen. The article is titled “Biocultural evidence of precise manual activities in an Early Holocene individual of the high-altitude Peruvian Andes.” The article discusses evidence of habitual precision grasping tasks in an early high-altitude Andean individual excavated from the Cuncaicha rockshelter, which is one of the highest-altitude Pleistocene archaeological sites worldwide.

Read the full article at: https://doi.org/10.1002/ajpa.24160

Abstract

“Objectives: Cuncaicha, a rockshelter site in the southern Peruvian Andes, has yielded archaeological evidence for human occupation at high elevation (4,480 masl) during the Terminal Pleistocene (12,500–11,200 cal BP), Early Holocene (9,500–9,000 cal BP), and later periods. One of the excavated human burials (Feature 15-06), corresponding to a middle-aged female dated to ~8,500 cal BP, exhibits skeletal osteoarthritic lesions previously proposed to reflect habitual loading and specialized crafting labor. Three small tools found in association with this burial are hypothesized to be associated with precise manual dexterity.

Materials and methods: Here, we tested this functional hypothesis through the application of a novel multivariate methodology for the three-dimensional analysis of muscle attachment surfaces (entheses). This original approach has been recently validated on both lifelong-documented anthropological samples as well as experimental studies in nonhuman laboratory samples. Additionally, we analyzed the three-dimensional entheseal shape and resulting moment arms for muscle opponens pollicis.

Results: Results show that Cuncaicha individual 15-06 shows a distinctive entheseal pattern associated with habitual precision grasping via thumb-index finger coordination, which is shared exclusively with documented long-term precision workers from recent historical collections. The separate geometric morphometric analysis revealed that the individual’s opponens pollicis enthesis presents a highly projecting morphology, which was found to strongly correlate with long joint moment arms (a fundamental component of force-producing capacity), closely resembling the form of Paleolithic hunter-gatherers from diverse geo-chronological contexts of Eurasia and North Africa.

Discussion: Overall, our findings provide the first biocultural evidence to confirm that the lifestyle of some of the earliest Andean inhabitants relied on habitual and forceful precision grasping tasks.”

11.29.20