Lower limb biomechanics and habitual mobility among mid-Holocene populations of the Cis-Baikal

Abstract

a b s t r a c tThe mid-Holocene hunteregatherer populations of the Cis-Baikal represent long-term occupation by the Early Neolithic Kitoi Culture (6800e4900 B.C.) and the Middle Neolithic and Bronze Age Isakovo, Serovo and Glazkovo (ISG) cultures (4200e1000 B.C.). While there is considerable evidence for cultural and genetic discontinuity between these populations, differences in habitual activity between these periods remain poorly understood. The current study uses cross sectional geometric (CSG) properties of the femur and tibia in the lower limb, to investigate variation in mechanical loading and terrestrial locomotion between the Kitoi and ISG cultural groups. The results demonstrate a significant decrease in femoral rigidity and a trend towards more circular femoral diaphyses among the later ISG groups which suggests that there was a significant decrease in terrestrial mobility across this transition. This trend is accompanied by significant declines in tibial rigidity among females, resulting in greater sexual dimorphism among the ISG than the Kitoi. This indicates a shift towards a sexual division of labour which involved greater sedentism of the ISG than Kitoi women. Overall, the results suggest that shifts in habitual activity throughout the mid-Holocene of the Cis-Baikal involved both increased sedentism, and an increase in sexual differences in logistical mobility.

The effect of diet and sociopolitical change on physiological stress and behavior in lateRoman‐EarlyByzantine (300–700AD) and Islamic (902–1,235AD) populations from Ibiza, Spain

“…Additionally, testosterone increases the sensitivity of the periosteum to loading, further contributing to greater male cross‐sectional properties (Frisancho, Garn, & Werner, 1970; Gabel, Macdonald, Nettlefold, & McKay, 2017; Högler et al, 2008; Orwoll, 2003; Schoenau, 2006). Consequently, males may appear more robust even if habitual loading levels relative to body size did not differ between the sexes (Stock & Macintosh, 2016). Culturally mediated variation in behavior, diet, and social status are also important sources of sexual differences in body size and cross‐sectional properties.…”

Diaphyseal cross‐sectional geometry of the metatarsal bones in the Jomon population

“…In this study, the total subperiosteal area (TA), polar section modulus ( Z p ), and shape ratio ( I max / I min ) were adopted to compare the CSG properties (Table ). TA is a measure of the total area of the periosteal contour and it is considered a good indicator of the overall rigidity of the bone diaphysis (Stock & Macintosh, ; Stock & Shaw, ). Our previous study of the fibula also adopted this parameter.…”

Ontogeny and variability of trabecular bone in the chimpanzee humerus, femur and tibia

“…Cortical bone morphology of the adult humerus and femur reflects variation in human activity levels (Macintosh, Pinhasi, & Stock, 2014;Macintosh, Pinhasi, & Stock, 2017;Shaw & Stock, 2013;Stock & Macintosh, 2016), as well as locomotor differences in extant apes, enabling the reconstruction of limb loading in fossil taxa (Ruff, 2008;Ruff, 2002;Ruff, Burgess, Ketcham, & Kappelman, 2016). Humans, gorillas and chimpanzees undergo changes in locomotion during ontogeny (Doran, 1992(Doran, , 1997Sarringhaus, MacLatchy, & Mitani, 2014;Sutherland, 1997;Sutherland, Olshen, Cooper, & Woo, 1980), which are reflected in limb bone cross-sectional geometry at various life stages (Cowgill, Warrener, Pontzer, & Ocobock, 2010;Gosman, Hubbell, Shaw, & Ryan, 2013;Ruff, 2003a;Ruff, Burgess, Bromage, Mudakikwa, & McFarlin, 2013;Sarringhaus, MacLatchy, & Mitani, 2016).…”