Behavioral inferences from the Skhul/Qafzeh early modern human hand remains

Abstract

Two groups of humans are found in the Near East Ϸ100,000 years ago, the late archaic Neanderthals and the early modern Skhul͞ Qafzeh humans. Observations that Neanderthals were more heavily muscled, had stronger upper-limb bones, and possessed unusual shapes and orientations of some upper-limb joint complexes relative to the Skhul͞Qafzeh hominids, have led some researchers to conclude that significant between-group upperlimb-related behavioral differences must have been present, despite the association of the two groups with similar Middle Paleolithic archeological complexes. A three-dimensional morphometric analysis of the hand remains of the Skhul͞Qafzeh hominids, Neanderthals, early and late Upper Paleolithic humans, and Holocene humans supports the dichotomy. The Skhul͞Qafzeh carpometacarpal remains do not have any unique morphologies relative to the other fossil samples remains examined. However, in the functionally significant metacarpal 1 and 3 bases they resemble Upper Paleolithic humans, not Neanderthals. Furthermore, the Skhul͞Qafzeh sample differs significantly from the Neanderthals in many other aspects of hand functional anatomy. Given the correlations between changes in tool technologies and functional adaptations seen in the hands of Upper Paleolithic humans, it is concluded that the Skhul͞Qafzeh hand remains were adapted to Upper Paleolithic-like manipulative repertoires. These results support the inference of significant behavioral differences between Neanderthals and the Skhul͞Qafzeh hominids and indicate that a significant shift in human manipulative behaviors was associated with the earliest stages of the emergence of modern humans.

Investigating interrelationships between Lower Palaeolithic stone tool effectiveness and tool user biometric variation: implications for technological and evolutionary changes

“…Although researchers have similarly suggested links between hominin biometric variation/capabilities and the preferential production and use of variable stone tool forms/types (e.g., Marzke and Shackley, 1987;Niewoehner, 2001Niewoehner, , 2006Sandgathe, 2005;Gowlett, 2009Gowlett, , 2015Lycett, 2013;Lycett and von Cramon-Taubadel, 2015;Key, 2016), direct evidence relating to these hypothesized relationships within Palaeolithic contexts is limited.…”

Estimating thumb–index finger precision grip and manipulation potential in extant and fossil primates

“…However, the simplicity of the model makes it applicable to fossil specimens for which only information about bony morphology is preserved. Human joint ranges of motion were used for all joints of the fossil H. sapiens and H. neanderthalensis specimens, because overall hand morphology is generally very similar [18]. Given the mosaic human-like and Pan-like morphology of Au.…”

“…These dexterous abilities and associated anatomy are traditionally considered to have evolved in response to removing the hands from the constraints of locomotion as well as the mechanical demands of intensive tool-use and tool-production in our fossil hominin ancestors [3,5,8,9]. However, there is still much debate about the inferred manipulative capabilities of early fossil hominins, particularly with regard to tool-use [10 -16] and potential subtle differences in precision grip movement or ability between Neanderthals and modern humans [17][18][19]. Furthermore, other primates, with markedly different hand morphology (e.g.…”

Evolution in leaps: The punctuated accumulation and loss of cultural innovations

“…Reasons for the sudden changes in hominid material culture in the archaeological record continue to be debated; they could be related to demographic factors (17), rapid cognitive change (18)(19)(20)(21), relatively sudden changes in hand morphology (22,23), or dramatic climatic shifts (10,(24)(25)(26)(27)(28). Further, intermediate-scale environmental change or migration to a new environment also could affect the accumulation and loss of traits that are primarily useful in specific environments (29)(30)(31)(32)(33).…”