Enrico Ryunosuke Crema

• PhD
• Associate Professor at University of Cambridge

This paper explores the robustness of phylogenetic methods for detecting variations in branching and blending signals in the archaeological record. Both processes can generate a spatial structure whereby cultural similarity between different sites decays with increasing spatial distance. By generating a series of artificial records through the cont...

Recently there has been growing interest in characterising population structure in cultural data in the context of ongoing debates about the potential of cultural group selection as an evolutionary process. Here we use archaeological data for this purpose, which brings in a temporal as well as spatial dimension. We analyse two distinct material cul...

A long tradition of cultural evolutionary studies has developed a rich repertoire of mathematical models of social learning. Early studies have laid the foundation of more recent endeavours to infer patterns of cultural transmission from observed frequencies of a variety of cultural data, from decorative motifs on potsherds to baby names and musica...

The adoption of rice farming during the first millennium BC was a turning point in Japanese prehistory, defining the subsequent cultural, linguistic, and genetic variation in the archipelago. Here, we use a suite of novel Bayesian techniques to estimate the regional rates of dispersal and arrival time of rice farming using radiocarbon dates on char...

The last decade saw a rapid increase in the number of studies where time–frequency changes of radiocarbon dates have been used as a proxy for inferring past population dynamics. Although its universal and straightforward premise is appealing and undoubtedly offers some unique opportunities for research on long-term comparative demography, practical...

Compared to what is found in many other scientific disciplines, archaeological data are typically scarce, biased and fragmented. This, coupled with the fact that archaeologists can rarely test their hypotheses using experimental design, makes archaeological inference and our ability to assess the robustness of quantitative methods used to make such...

Chemical analyses of archaeological artefacts are often used for provenance studies and for assessing whether specific performance characteristics were targeted by craftspeople in the past. Traditionally, the answers to these questions were sought by identifying compositional averages and by studying their correlations with either the geochemical s...

Previous research in the evolutionary and psychological sciences has suggested that markers or tags of ethnic or group membership may help to solve cooperation and coordination problems. Cheating remains, however, a problem for these views, insofar as it is possible to fake the tag. While evolutionary psychologists have suggested that humans evolve...

Rice agriculture was brought to Japan during the first millennium BC by migrant communities of farmers from the Korean peninsula. Substantial geographic variation is observed in the uptake of this new subsistence economy, reflecting different forms of interaction between farmers and foragers. Here, the authors analyse a combination of settlement an...

Intralimb proportions provide insights into growth, development, populations history, and adaptation across human groups. However, the conventional approach of calculating brachial and crural indices for individual skeletons and comparing assemblages using sample means is not feasible in commingled remains. This study aims to assess the reliability...

Rice and millet arrived in Western Japan from Korea around 3,000 years ago and spread eastwards across the archipelago in the next 700 years. However, the extent to which agriculture transformed traditional Jōmon hunter-gatherer-fisher communities is debated. Central Japan is a key area of study as remodelling of radiocarbon dates shows a slowdown...

Aoristic analysis is often used to handle chronological uncertainties of datasets where scientific dates (e.g., 14 C and OSL) are unavailable, and observations are described by association to archaeological periods or phases. Although several advances have been made over the last 2 decades, the basic principle of this approach remains fundamentally...

Archaeological data provide a potential to investigate the diffusion of technological and cultural traits. However, much of this research agenda currently needs more formal quantitative methods to address small sample sizes and chronological uncertainty. This paper introduces a novel Bayesian framework for inferring the shape of diffusion curves us...

The record of past human adaptations provides crucial lessons for guiding responses to crises in the future1–3. To date, there have been no systematic global comparisons of humans’ ability to absorb and recover from disturbances through time4,5. Here we synthesized resilience across a broad sample of prehistoric population time–frequency data, span...

The GINI project investigates the dynamics of inequality among populations over the long term by synthesising global archaeological housing data. This project brings archaeologists together from around the world to assess hypotheses concerning the causes and consequences of inequality that are of relevance to contemporary societies globally.

The record of past human adaptations provides crucial lessons for guiding responses to crises in the future. To date, there have been no systematic global comparisons of humans’ ability to absorb and recover from disturbances through time. We present results of the first attempt to synthesise resilience across a broad sample of prehistoric populati...

The cross-fertilisation between biological and cultural evolution has led to an extensive borrowing of key concepts, theories, and statistical methods for studying temporal variation in the frequency of cultural variants. Archaeologists have been among the front-runners of those engaging with this endeavour, and the last 2 decades have seen a numbe...

We examine the changing importance of wild starch rich plant staples, predominantly tree nuts, in early agricultural societies in East Asia and Europe, focusing on Korea, Japan, and Britain. A comparative review highlights variations in the importance of wild plant staples compared to domesticated crops. The Korean Middle to Late Chulmun periods (c...

Human beings are an active component of every terrestrial ecosystem on Earth. Although our local impact on the evolution of these ecosystems has been undeniable and extensively documented, it remains unclear precisely how our activities are altering them, in part because ecosystems are dynamic systems structured by complex, non-linear feedback proc...

We present a species distribution model (SDM) of Fagopyrum esculentum (buckwheat) in China using present distribution data and estimates for the past based on palaeoclimatic reconstructions. Our model estimates the potential area suitable for buckwheat cultivation over the last 8,000 years, with northeast China consistently showing the highest suit...

Fieldwork is crucial to advancing knowledge in archaeology and anthropology, but previous works suggests that between 64 and 68 percent of respondents experience sexual misconduct during fieldwork. Going forward, fieldwork must be made safe and inclusive. To achieve this, we must understand why sexual misconduct takes place during fieldwork. We sur...

Modelling in demographic ecology offers insights into population stability and instability in village societies. In this study we explore the hypothesis that among storage dependent fisher-hunter-gatherers, access to high resource diversity favors reduced demographic volatility over time. To better understand this relationship, we generate summed p...

The adoption of rice farming during the 1st millennium BC was a turning point in Japanese prehistory, defining the subsequent cultural, linguistic, genetic variation in the archipelago. Here we employ a suite of novel Bayesian techniques to estimate the regional rates of dispersal and arrival time of rice farming using radiocarbon dates on charred...

Fieldwork is crucial to advancing knowledge in archaeology and anthropology, but previous works suggests that between 64-68% of respondents experience sexual misconduct during fieldwork. Going forward, fieldwork must be made safe and inclusive. To achieve this, we must understand why sexual misconduct takes place during fieldwork. We surveyed an in...

The last decade saw a rapid increase in the number of applications where time-frequency changes of radiocarbon dates have been used as a proxy for inferring past population dynamics. Although its simple and universal premise is appealing and undoubtedly offers some unique opportunities for research on long-term comparative demography, practical app...

We investigate the relationship between climatic and demographic events in Korea during the Chulmun period (10,000–3,500 cal. BP) by analyzing paleoenvironmental proxies and 14C dates. We focus on testing whether a cooling climate, and its potential negative impact on millet productivity around the mid 5th-millennium cal. BP, triggered the populati...

Accents, along with other cultural features including shared place of origin, helped to increase the number of people with whom an individual could signal cooperative tendencies (Cohen, 2012). Yet as groups became larger and underwent continued fission and fusion, signals of group membership may have become more important to reduce the risk of infi...

We investigate the relationship between climatic and demographic events in Korea during the Chulmun period (10,000–3,500 cal. BP) by analyzing paleoenvironmental proxies and ¹⁴ C dates. We focus on testing whether a cooling climate, and its potential impact on millet productivity around 4,500 cal. BP triggered the population decline observed in the...

Examining how past human populations responded to environmental and climatic changes is a central focus of the historical sciences. The use of summed probability distributions (SPD) of radiocarbon dates as a proxy for estimating relative population sizes provides a widely applicable method in this research area. Paleodemographic reconstructions and...

Large sets of radiocarbon dates are increasingly used as proxies for inferring past population dynamics and the last few years, in particular, saw an increase in the development of new statistical techniques to overcome some of the key challenges imposed by this kind of data. These include: 1) null hypothesis significance testing approaches based o...

Large sets of radiocarbon dates are increasingly used as a proxy for inferring past population dynamics and the last few years saw the development of several new statistical techniques to overcome some of the key challenges imposed by this kind of data. These include: 1) null hypothesis significance testing approaches based on Monte-Carlo simulatio...

This paper responds to a resurgence of interest in constructing long-term time proxies of human activity, especially but not limited to models of population change over the Pleistocene and/or Holocene. While very much agreeing with the need for this increased attention, we emphasize three important issues that can all be thought of as modifiable re...

The last decade has seen the development of a range of new statistical and computational techniques for analysing large collections of radiocarbon (14 C) dates, often but not exclusively to make inferences about human population change in the past. Here we introduce rcarbon, an open-source software package for the R statistical computing language w...

One of the most significant challenges for cultural evolution is the inference of macroevolutionary patterns from historical and archaeological sources of cultural data. Here, we examine the utility of diversification rate analysis for observing trends in the mode and tempo of cultural evolution using simulated cultural data sets. We explore a rang...

We introduce a new workflow for analysing archaeological frequency data associated with relative rather than absolute chronological time-stamps. Our approach takes into account multiple sources of uncertainty by combining Bayesian chronological models and Monte-Carlo simulation to sample possible calendar dates for each archaeological entity. We ar...

The MedAfriCarbon radiocarbon database and its accompanying web application are outcomes of the MedAfrica project — Archaeological deep history and dynamics of Mediterranean Africa, ca. 9600–700 BC. The dataset presented here in Version 1.0 of the database includes 1587 archaeological 14C dates from 368 sites in Mediterranean Africa. The database i...

The focus of this paper is the Neolithic of northwest Europe, where a rapid growth in population between ~5950 and ~5550 cal yr BP is followed by a decline that lasted until ~4950 cal yr BP. The timing of the increase in population density correlates with the local appearance of farming and is attributed to the advantageous effects of agriculture....

Past population dynamics play a key role in integrated models of socio-cultural change in Polynesia. A key aspect of these models is the interplay between food production and population growth. Located on the margins of Polynesia, New Zealand presented considerable challenges to traditional Polynesian food production, many crops were not successful...

In this study, we compare the genetic ancestry of individuals from two as yet genetically unstudied cultural traditions in Estonia in the context of available modern and ancient datasets: 15 from the Late Bronze Age stone-cist graves (1200–400 BC) (EstBA) and 6 from the Pre-Roman Iron Age tarand cemeteries (800/500 BC–50 AD) (EstIA). We also includ...

Statistical inference lies at the foundation of modern science and at the core of scientific inquiry in archaeology. It provides a suite of formal methods for describing populations from sample data, and enables the assessment and comparison of archaeological hypotheses formulated as statistical models. This essay reviews the basic premises of the...

In this chapter we review the application of neutral theory to archaeological case studies. In particular, we focus on commonly used neutrality tests and discuss the interpretation of their results. We argue that one needs to be careful with interpreting the consistency (or inconsistency) of archaeological data with theoretical neutral expectations...

In their letter, d’Huy et al. (1) challenge the novelty of our study (2), and question the reliability of some our results in the light of previous folkloric research and geographic biases in the Aarne Thompson Uther (ATU) index (3). In our reply we explain how their criticisms are already largely addressed in our paper (2) or based on misunderstan...

Summed probability distributions of radiocarbon dates are an increasingly popular means by which to reconstruct prehistoric population dynamics, enabling more thorough cross-regional comparison and more robust hypothesis testing, for example with regard to the impact of climate change on past human demography. Here we review another use of such sum...

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Significance This paper presents unprecedented evidence on the transmission mechanism underlying the spread of a broad cross-cultural assemblage of folktales in Eurasia and Africa. State-of-the-art genomic evidence is used to directly assess the relevance of demic diffusion processes, in particular on the distribution of Old World folktales at inte...

We present preliminary results of an Earth observation approach for the study of past human occupation and landscape reconstruction in the Central Sahara. This region includes a variety of geomorphological features such as palaeo-oases, dried river beds, alluvial fans and upland plateaux whose geomorphological characteristics, in combination with c...

We present preliminary results of an Earth observation approach for the study of past human occupation and landscape reconstruction in the Central Sahara. This region includes a variety of geomorphological features such as palaeo-oases, dried river beds, alluvial fans and upland plateaux whose geomorphological characteristics, in combination with c...

Accurate determination of the origin and timing of trauma is key in medicolegal investigations when the cause and manner of death are unknown. However, distinction between criminal and accidental perimortem trauma and postmortem modifications can be challenging when facing unidentified trauma. Postmortem examination of the immersed victims of the Y...

A long tradition of cultural evolutionary studies has developed a rich repertoire of mathematical models of social learning. Early studies have laid the foundation of more recent endeavours to infer patterns of cultural transmission from observed frequencies of a variety of cultural data, from decorative motifs on potsherds to baby names and musica...

Observable patterns of cultural variation are consistently intertwined with demic movements, cultural diffusion, and adaptation to different ecological contexts (Cavalli-Sforza and Feldman 1981; Boyd and Richerson 1985). The quantitative study of gene-culture co-evolution has focused in particular on the mechanisms responsible for change in frequen...

Recent advances in the use of summed probability distribution (SPD) of calibrated 14C dates have opened new possibilities for studying prehistoric demography. The degree of correlation between climate change and population dynamics can now be accurately quantified, and divergences in the demographic history of distinct geographic areas can be stati...

Time-series of pithouse and site counts. Time-series of pithouse and site counts: a) pithouse counts in Saitama, Kanagawa, and Tokyo prefectures (95% confidence intervals obtained from 1,000 Monte-Carlo iterations; details in [21]); b) rate of change estimates of pithouse counts in Saitama, Kanagawa, and Tokyo prefectures (95% confidence intervals...

Results of the SPD analysis using14C dates with δ13C < -26‰. (PDF)

R Source Code, Scripts, and Data. (ZIP)

Recent advances in the use of summed probability distribution (SPD) of calibrated $^{14}$C dates have opened new possibilities for studying prehistoric demography. The degree of correlation between climate change and population dynamics can now be accurately quantified, and divergences in the demographic history of distinct geographic areas can be...

We examined the settlement structure from the Kel Tadrart Tuareg, a small pastoral society from southwest Libya. Our objective was to apply spatial analysis to establish the statistical significance of specific patterns in the settlement layout. In particular, we examined whether there is a separation between domestic and livestock spaces, and whet...

The datasets described in this paper comprise the core spatial and temporal structure of the Cultural Evolution of Neolithic Europe project (EUROEVOL), led by Professor Stephen Shennan, UCL. This is one of three datasets resulting from the EUROEVOL project, the other two comprising the faunal (EUROEVOL Dataset 2) and archaeobotanical (EUROEVOL Data...

Supplementary material for the paper: Crema, E. R., Kandler, A., Shennan, S. "Revealing patterns of cultural transmission from frequency data: equilibrium and non-equilibrium assumptions" Scientific Reports 6, 39122; doi: 10.1038/srep39122 (2016). Updated versions of the code can be found on: https://github.com/ercrema/CulturalTransmissionModel

Our analysis of over 28,000 osteometric measurements from fossil remains dating between c. 5600 and 1500 BCE reveals a substantial reduction in body mass of 33% in Neolithic central European domestic cattle. We investigate various plausible explanations for this phenotypic adaptation, dismissing climatic change as a causal factor, and further rejec...

Relative frequencies of male, female and castrate bones per site phases identified using osteometric and morphological criteria. (CSV)

Mean Log Size Index and Standard deviation per site phase for each species, including associated sample size, sitename, estimated mean date, period and cultural affiliation. (CSV)

Several forms of social learning rely on the direct or indirect evaluation of the fitness of cultural traits. Here we argue, via a simple agent-based model, that payoff uncertainty, that is the correlation between a trait and the signal used to evaluate its fitness, plays a pivotal role in the spread of beneficial innovation. More specifically, we...

This chapter proposes a model of long-term changes in human settlement pattern to identify possible generative processes behind empirically observed fluctuations in settlement rank-size pattern. The model assumes that per-capita fitness is a combination of the beneficial effect derived from the presence of other individuals in the same group and th...

This dataset comprises the primary data collected for the Cultural Evolution of Neolithic Europe project (EUROEVOL), led by Professor Stephen Shennan, UCL. The dataset offers the largest repository of archaeological site and radiocarbon data from Neolithic Europe (4,757 sites and 14,131 radiocarbon samples), dating between the late Mesolithic and E...

Identifying the processes by which human cultures spread across different populations is one of the most topical objectives shared among different fields of study. Seminal works have analyzed a variety of data and attempted to determine whether empirically observed patterns are the result of demic and/or cultural diffusion. This special issue colle...

If archaeology is to take a leading role in the social sciences, new theoretical and methodological advances emerging from the natural sciences cannot be ignored. This requires considerable retooling for archaeology as a discipline at a population scale of analysis. Such an approach is not easy to carry through, especially owing to historically con...

In a previous study we presented a new method that used summed probability distributions (SPD) of radiocarbon dates as a proxy for population levels, and Monte-Carlo simulation to test the significance of the observed fluctuations in the context of uncertainty in the calibration curve and archaeological sampling. The method allowed us to identify p...

Archaeologists have long sought appropriate ways to describe the duration and floruit of archaeological cultures in statistical terms. Thus far, chronological reasoning has been largely reliant on typological sequences. Using summed probability distributions, the authors here compare radiocarbon dates for a series of European Neolithic cultures wit...

A wide range of theories and methods inspired from evolutionary biology have recently been used to investigate temporal changes in the frequency of archaeological material. Here we follow this research agenda and present a novel approach based on Approximate Bayesian Computation (ABC), which enables the evaluation of multiple competing evolutionary...

The exploitation of marine molluscs by Mediterranean hunter-gatherers increased from the Upper Palaeolithic onwards, although their role in subsistence has rarely been investigated fully. An ideal area to address this issue is the archipelago of the égadi Islands, most of which were isolated by Post-Glacial sea level rise. Here we report on the res...

This paper explores the way cultural traits are transmitted between individuals, and the degree to which this is affected by the location, size and configuration of human settlements, as well as other aspects of the intervening landscape. Drawing upon case studies from the large Greek island of Cere, we first consider dialectal variants of variants...

This paper combines point-process modelling, visibility analysis and an information criteria approach to infer the reasons behind the Bronze Age settlement pattern of Leskernick Hill in Cornwall, UK. We formalise three alternative hypotheses as point process models characterised by different combinations of covariates. In addition to using traditio...

Japanese archaeology benefits from the large number of rescue excavations conducted during recent decades that have led to an unparalleled record of archaeological sites. That record is here put to use to interrogate changing settlement patterns in the north-eastern corner of Tokyo Bay during several millennia of the Jomon period (Early, Middle and...

Archaeological analyses often detect abrupt changes over time in the hierarchy of settlement sizes and the spatial distribution of residential units. These transformations have been explained looking at a variety of possible causes, from climatic changes to the sudden release of slowly cumulating political tensions. While many of these models offer...

The Jomon culture is a tradition of complex hunter-gatherers which rose in the Japanese archipelago at the end of the Pleistocene (ca. 13,000 cal BP) and lasted until the 3rd millennium cal BP. Recent studies increasingly suggest how this long cultural persistence was characterised by repeated episodes of change in settlement pattern, primarily man...

site, as an archaeological concept, has no role to play in the discipline. Its uses are not warranted by its properties. It obscures critical theoretical and methodological deficiencies, and it imparts a serious and unredeemable systematic error in re-covery and management programs. In spite of the technical problems its abandonment will cause, the...

This paper discusses the problem of temporal uncertainty in archaeological analysis and how it affects archaeological interpretation. A probabilistic method is proposed as a potential solution for modelling and quantifying time when high levels of uncertainty restricts temporal knowledge and scientific datings are unavailable, while Monte Carlo sim...

Oyumino district (Chiba City, Chiba Prefecture, Japan) is a small residential area which has been intensely investigated as part of an urban development project during the 1970s~90s. The emergency excavations have yielded a vast amount of archaeological materials from different historic and prehistoric periods, including numerous hunter-gatherer se...