The revolution that wasn't: a new interpretation of the origin of modern human behavior.

Not by Genes Alone: How Culture Transformed Human Evolution

Many ``real-world'' networks are clearly defined while most ``social'' networks are to some extent subjective. Indeed, the accuracy of empirically-determined social networks is a question of some concern because individuals may have distinct perceptions of what constitutes a social link. One unambiguous type of connection is sexual contact. Here we analyze data on the sexual behavior of a random sample of individuals, and find that the cumulative distributions of the number of sexual partners during the twelve months prior to the survey decays as a power law with similar exponents $\alpha \approx 2.4$ for females and males. The scale-free nature of the web of human sexual contacts suggests that strategic interventions aimed at preventing the spread of sexually-transmitted diseases may be the most efficient approach.

The Web of Human Sexual Contacts

We generated genome-wide data from 69 Europeans who lived between 8,000-3,000 years ago by enriching ancient DNA libraries for a target set of almost 400,000 polymorphisms. Enrichment of these positions decreases the sequencing required for genome-wide ancient DNA analysis by a median of around 250-fold, allowing us to study an order of magnitude more individuals than previous studies and to obtain new insights about the past. We show that the populations of Western and Far Eastern Europe followed opposite trajectories between 8,000-5,000 years ago. At the beginning of the Neolithic period in Europe, ∼8,000-7,000 years ago, closely related groups of early farmers appeared in Germany, Hungary and Spain, different from indigenous hunter-gatherers, whereas Russia was inhabited by a distinctive population of hunter-gatherers with high affinity to a ∼24,000-year-old Siberian. By ∼6,000-5,000 years ago, farmers throughout much of Europe had more hunter-gatherer ancestry than their predecessors, but in Russia, the Yamnaya steppe herders of this time were descended not only from the preceding eastern European hunter-gatherers, but also from a population of Near Eastern ancestry. Western and Eastern Europe came into contact ∼4,500 years ago, as the Late Neolithic Corded Ware people from Germany traced ∼75% of their ancestry to the Yamnaya, documenting a massive migration into the heartland of Europe from its eastern periphery. This steppe ancestry persisted in all sampled central Europeans until at least ∼3,000 years ago, and is ubiquitous in present-day Europeans. These results provide support for a steppe origin of at least some of the Indo-European languages of Europe.

Massive migration from the steppe was a source for Indo-European languages in Europe

This article evaluates theories of the origins of sex differences in human behavior. It reviews the cross-cultural evidence on the behavior of women and men in nonindustrial societies, especially the activities that contribute to the sex-typed division of labor and patriarchy. To explain the cross-cultural findings, the authors consider social constructionism, evolutionary psychology, and their own biosocial theory. Supporting the biosocial analysis, sex differences derive from the interaction between the physical specialization of the sexes, especially female reproductive capacity, and the economic and social structural aspects of societies. This biosocial approach treats the psychological attributes of women and men as emergent given the evolved characteristics of the sexes, their developmental experiences, and their situated activity in society.

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A cross-cultural analysis of the behavior of women and men: implications for the origins of sex differences.

Language, Genes, and Cultural Interaction

© 2005 Taylor & Francis. All rights reserved. In recent decades archaeologists have been extremely sceptical of invoking environmental factors to account for cultural and social change. The increasing availability of archaeological and climatic data with high degrees of temporal resolution has meant that the study of such questions now has a much more substantial database. However, even with improved chronological resolution, identifying causal connections remains difficult. This chapter examines three case studies where climatic factors have been used to explain demographic decline, the circum-Alpine Neolithic in the later 4th millennium, the East Mediterranean in the late 3rd millennium and the arid southwest of North America AD 400-1400, and emphasizes the importance of understanding patterns of costs and benefits to people in particular local situations. Although the issues involved are complex, the impact of climate change on past human societies and economies should not be ignored or considered insignificant.

Holocene climate and human populations: An archaeological approach

Their Commonwealths are not as We Supposed

Ethnic ambiguity: a cultural evolutionary perspective

/pdf/supply-and-demand-in-prehistory-economics-of-neolithic-1lmq3cs4p6.pdf

Stephen Shennan

Papers

Language, Genes, and Cultural Interaction

Holocene climate and human populations: An archaeological approach

Their Commonwealths are not as We Supposed

Ethnic ambiguity: a cultural evolutionary perspective

Supply and Demand in Prehistory? Economics of Neolithic Mining in NW Europe (NEOMINE)