Breadth of Humanity
Human culture is uniquely open-ended rather than uniquely cumulative
Thomas Morgan & Marcus Feldman
Nature Human Behaviour, January 2025, Pages 28-42
Abstract:
Theories of how humans came to be so ecologically dominant increasingly centre on the adaptive abilities of human culture and its capacity for cumulative change and high-fidelity transmission. Here we revisit this hypothesis by comparing human culture with animal cultures and cases of epigenetic inheritance and parental effects. We first conclude that cumulative change and high transmission fidelity are not unique to human culture as previously thought, and so they are unlikely to explain its adaptive qualities. We then evaluate the evidence for seven alternative explanations: the inheritance of acquired characters, the pathways of inheritance, the non-random generation of variation, the scope of heritable variation, effects on organismal fitness, effects on genetic fitness and effects on evolutionary dynamics. From these, we identify the open-ended scope of human cultural variation as a key, but generally neglected, phenomenon. We end by articulating a hypothesis for the cognitive basis of this open-endedness.
The genetic origin of the Indo-Europeans
Iosif Lazaridis et al.
Nature, forthcoming
Abstract:
The Yamnaya archaeological complex appeared around 3300 BC across the steppes north of the Black and Caspian Seas, and by 3000 BC it reached its maximal extent, ranging from Hungary in the west to Kazakhstan in the east. To localize Yamnaya origins among the preceding Eneolithic people, we assembled ancient DNA from 435 individuals, demonstrating three genetic clines. A Caucasus–lower Volga (CLV) cline suffused with Caucasus hunter-gatherer ancestry extended between a Caucasus Neolithic southern end and a northern end at Berezhnovka along the lower Volga river. Bidirectional gene flow created intermediate populations, such as the north Caucasus Maikop people, and those at Remontnoye on the steppe. The Volga cline was formed as CLV people mixed with upriver populations of Eastern hunter-gatherer ancestry, creating hypervariable groups, including one at Khvalynsk. The Dnipro cline was formed when CLV people moved west, mixing with people with Ukraine Neolithic hunter-gatherer ancestry along the Dnipro and Don rivers to establish Serednii Stih groups, from whom Yamnaya ancestors formed around 4000 BC and grew rapidly after 3750–3350 BC. The CLV people contributed around four-fifths of the ancestry of the Yamnaya and, entering Anatolia, probably from the east, at least one-tenth of the ancestry of Bronze Age central Anatolians, who spoke Hittite. We therefore propose that the final unity of the speakers of ‘proto-Indo-Anatolian’, the language ancestral to both Anatolian and Indo-European people, occurred in CLV people some time between 4400 BC and 4000 BC.
A genomic history of the North Pontic Region from the Neolithic to the Bronze Age
Alexey Nikitin et al.
Nature, forthcoming
Abstract:
The North Pontic Region was the meeting point of the farmers of Old Europe and the foragers and pastoralists of the Eurasian steppe, and the source of migrations deep into Europe. Here we report genome-wide data from 81 prehistoric North Pontic individuals to understand the genetic makeup of its people. North Pontic foragers had ancestry from Balkan and Eastern hunter-gatherers as well as European farmers and, occasionally, Caucasus hunter-gatherers. During the Eneolithic period, a wave of migrants from the Caucasus–Lower Volga area bypassed local foragers to mix in equal parts with Trypillian farmers, forming the people of the Usatove culture around 4500 BCE. A temporally overlapping wave of migrants from the Caucasus–Lower Volga blended with foragers instead of farmers to form Serednii Stih people. The third wave was the Yamna -- descendants of the Serednii Stih who formed by mixture around 4000 BCE and expanded during the Early Bronze Age (3300 BCE). The temporal gap between Serednii Stih and the Yamna is bridged by a genetically Yamna individual from Mykhailivka, Ukraine (3635–3383 BCE), a site of archaeological continuity across the Eneolithic–Bronze Age transition and a likely epicentre of Yamna formation. Each of these three waves of migration propagated distinctive ancestries while also incorporating outsiders, a flexible strategy that may explain the success of the peoples of the North Pontic in spreading their genes and culture across Eurasia.
Earliest Movement of Sarsen Into the Stonehenge Landscape: New Insights from Geochemical and Visibility Analysis of the Cuckoo Stone and Tor Stone
Phil Harding et al.
Proceedings of the Prehistoric Society, forthcoming
Abstract:
This paper presents the results of new research on two sarsen stones, known as the Cuckoo Stone and Tor Stone, both former standing stones that lie on opposite banks of the River Avon and straddle the eastern border of the Stonehenge and Avebury World Heritage Site. Geochemical analysis indicates that both stones were probably transported to their present site from West Woods on the Marlborough Downs in north Wiltshire, a source that likely also supplied the large sarsen monoliths at Stonehenge. The paper examines the geological conditions necessary for the formation of sarsen across the site of the present-day Salisbury Plain to address the apparent absence of natural sarsen in the area. The results are integrated with those of archaeological fieldwork from nearby contemporaneous sites to suggest that the Cuckoo Stone and Tor Stone were probably introduced into the Stonehenge landscape in the early part of the Late Neolithic period, ie, contemporary with Phase 1 of Stonehenge and some 400–500 years before the construction of the principal sarsen settings at the monument. Visibility analysis indicates that the two stones were probably intervisible and likely to have formed part of a planned landscape and were positioned to create a formal portal to the Stonehenge area on either bank of the River Avon.
Running performance in Australopithecus afarensis
Karl Bates et al.
Current Biology, 6 January 2025, Pages 224-230
Abstract:
The evolution of bipedal gait is a key adaptive feature in hominids, but the running abilities of early hominins have not been extensively studied. Here, we present physics simulations of Australopithecus afarensis that demonstrate this genus was mechanically capable of bipedal running but with absolute and relative (size-normalized) maximum speeds considerably inferior to modern humans. Simulations predicted running energetics for Australopithecus that are generally consistent with values for mammals and birds of similar body size, therefore suggesting relatively low cost of transport across a limited speed range. Through model parameterization, we demonstrate the key role of ankle extensor muscle architecture (e.g., the Achilles tendon) in the evolution of hominin running energetics and indeed in an increase in speed range, which may have been intrinsically coupled with enhanced endurance running capacity. We show that skeletal strength was unlikely to have been a limiting factor in the evolution of enhanced running ability, which instead resulted from changes to muscle anatomy and particularly overall body proportions. These findings support the hypothesis that key features in the human body plan evolved specifically for improved running performance and not merely as a byproduct of selection for enhanced walking capabilities.
‘Symbolically Overloaded’ Burials: Early Fourth-Millennium BC Hunter-Fisher-Gatherer Mortuary Practices from North-Eastern Europe
Marja Ahola, Aija Macāne & Kerkko Nordqvist
European Journal of Archaeology, forthcoming
Abstract:
At the beginning of the fourth millennium BC, the Typical Comb Ware culture (TCW) emerged in north-eastern Europe. One of its characteristics is a wealth of ‘amber’ or ‘ochre’ graves and mortuary practices. This article concerns the graves’ key elements, their distribution and frequency, and their relationship to the TCW phenomenon. The analysis of seventy-seven graves from twenty-three sites suggests that TCW graves are a materialization of a complex set of practices in which visual aspects (colours, contrasts, and combinations of materials) and performance play significant roles. Given the small number and distribution of graves, these practices were reserved for particular people and/or occasions, and the tradition only lasted for a few centuries. Interpreted from the perspective of identity production and sociocultural networks, these graves and associated practices are defined as ‘symbolically overloaded’, with buried bodies and activities intended to be seen.