Kevin Lewis

May 17, 2020

Open Chests and Broken Hearts: Ritual Sequences and Meanings of Human Heart Sacrifice in Mesoamerica
Vera Tiesler & Guilhem Olivier
Current Anthropology, April 2020, Pages 168-193


Beyond the general idea of benefiting society and placating the divine, the polyvalent symbols and meanings of ancient religious sacrifices can be interpreted properly only after combining different disciplinary lenses. In this paper, we systematically scrutinize iconographic and ethnohistorical testimonies together with new skeletal and forensic evidence from across the Mesoamerican landscape in order to survey Mesoamerican heart sacrifices. Here we focus on three different heart-extraction procedures, two of which are characterized for the first time. Each reconstructed method (i.e., from below the chest cavity, between two left ribs, and through the sternal bone) provides novel cues regarding the array of ceremonial devices and native concepts of the human body as a cosmic model. Its partitioning and the liberation of vitalizing matter (namely, the heart and blood) fed specific sacred forces during divine cult and mythic reenactment. As for the Aztecs, we conclude that different trunk-opening procedures were practiced as part of ritual sequences that in each case enabled access to the Cosmic Sacred Mountain with its vivifying essences. In this context, native conceptions surrounding the distinctive heart-extraction techniques pose new proxies for analogous sacrificial practices in other parts of the world still awaiting systematic scrutiny.

Paternal provisioning results from ecological change
Ingela Alger et al.
Proceedings of the National Academy of Sciences, forthcoming


Paternal provisioning among humans is puzzling because it is rare among primates and absent in nonhuman apes and because emergent provisioning would have been subject to paternity theft. A provisioning “dad” loses fitness at the hands of nonprovisioning, mate-seeking “cads.” Recent models require exacting interplay between male provisioning and female choice to overcome this social dilemma. We instead posit that ecological change favored widespread improvements in male provisioning incentives, and we show theoretically how social obstacles to male provisioning can be overcome. Greater availability of energetically rich, difficult-to-acquire foods enhances female–male and male–male complementarities, thus altering the fitness of dads versus cads. We identify a tipping point where gains from provisioning overcome costs from paternity uncertainty and the dad strategy becomes viable. Stable polymorphic states are possible, meaning that dads need not necessarily eliminate cads. Our simulations suggest that with sufficient complementarities, dads can emerge even in the face of high paternity uncertainty. Our theoretical focus on ecological change as a primary factor affecting the trade-off between male mating and parenting effort suggests different possibilities for using paleo-climatic, archaeological, and genomic evidence to establish the timing of and conditions associated with emergence of paternal provisioning in the hominin lineage.

A 300,000-year-old throwing stick from Schöningen, northern Germany, documents the evolution of human hunting
Nicholas Conard et al.
Nature Ecology & Evolution, May 2020, Pages 690–693


The poor preservation of Palaeolithic sites rarely allows the recovery of wooden artefacts, which served as key tools in the arsenals of early hunters. Here, we report the discovery of a wooden throwing stick from the Middle Pleistocene open-air site of Schöningen that expands the range of Palaeolithic weaponry and establishes that late Lower Palaeolithic hominins in Northern Europe were highly effective hunters with a wide array of wooden weapons that are rarely preserved in the archaeological record.

Initial Upper Palaeolithic Homo sapiens from Bacho Kiro Cave, Bulgaria
Jean-Jacques Hublin et al.
Nature, forthcoming


The Middle to Upper Palaeolithic transition in Europe witnessed the replacement and partial absorption of local Neanderthal populations by Homo sapiens populations of African origin. However, this process probably varied across regions and its details remain largely unknown. In particular, the duration of chronological overlap between the two groups is much debated, as are the implications of this overlap for the nature of the biological and cultural interactions between Neanderthals and H. sapiens. Here we report the discovery and direct dating of human remains found in association with Initial Upper Palaeolithic artefacts, from excavations at Bacho Kiro Cave (Bulgaria). Morphological analysis of a tooth and mitochondrial DNA from several hominin bone fragments, identified through proteomic screening, assign these finds to H. sapiens and link the expansion of Initial Upper Palaeolithic technologies with the spread of H. sapiens into the mid-latitudes of Eurasia before 45 thousand years ago. The excavations yielded a wealth of bone artefacts, including pendants manufactured from cave bear teeth that are reminiscent of those later produced by the last Neanderthals of western Europe. These finds are consistent with models based on the arrival of multiple waves of H. sapiens into Europe coming into contact with declining Neanderthal populations.

Ancient DNA indicates human population shifts and admixture in northern and southern China
Melinda Yang et al.
Science, forthcoming


Human genetic history in East Asia is poorly understood. To clarify population relationships, we obtained genome wide data from 26 ancient individuals from northern and southern East Asia spanning 9,500-300 years ago. Genetic differentiation was higher in the past than the present, reflecting a major episode of admixture involving northern East Asian ancestry spreading across southern East Asia after the Neolithic, transforming the genetic ancestry of southern China. Mainland southern East Asian and Taiwan Strait island samples from the Neolithic show clear connections with modern and ancient samples with Austronesian-related ancestry, supporting a southern China origin for proto-Austronesians. Connections among Neolithic coastal groups from Siberia and Japan to Vietnam indicate that migration and gene flow played an important role in the prehistory of coastal Asia.

Genomic history and ecology of the geographic spread of rice
Rafal Gutaker et al.
Nature Plants, May 2020, Pages 492–502


Rice (Oryza sativa) is one of the world’s most important food crops, and is comprised largely of japonica and indica subspecies. Here, we reconstruct the history of rice dispersal in Asia using whole-genome sequences of more than 1,400 landraces, coupled with geographic, environmental, archaeobotanical and paleoclimate data. Originating around 9,000 yr ago in the Yangtze Valley, rice diversified into temperate and tropical japonica rice during a global cooling event about 4,200 yr ago. Soon after, tropical japonica rice reached Southeast Asia, where it rapidly diversified, starting about 2,500 yr BP. The history of indica rice dispersal appears more complicated, moving into China around 2,000 yr BP. We also identify extrinsic factors that influence genome diversity, with temperature being a leading abiotic factor. Reconstructing the dispersal history of rice and its climatic correlates may help identify genetic adaptations associated with the spread of a key domesticated species.


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