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Tools and ornaments found in a South African cave are almost identical to those San hunter-gatherers still use 40 millennia later.
Archaeologist João Zilhão and his critics trade charges over who truly invented artifacts at European sites—and whether Neandertals were “modern”.
That year, a team led by anthropologist Jean-Jacques Hublin, now at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, published a pivotal paper in Nature concluding that the Châtelperronian had been made by Neandertals. But Hublin's team concluded that the ornaments were the result of “acculturation” with modern humans, meaning that the Neandertals had either imitated modern human behavior or even gotten the ornaments through exchange or trade. Zilhão was outraged. “This was an extraordinary conclusion,” he says. He saw it as a sign of bias against the Neandertals, an assumption that they were not capable of inventing the ornaments themselves. In 1998, Zilhão, archaeologist Francesco D'Errico of the University of Bordeaux in France, and others published a long paper in Current Anthropology challenging the acculturation model and arguing that Neandertals had invented the Châtelperronian independently.
Genome study may explain links between paternal age and conditions such as autism.
pnas109-13220-Supplement.xlsx
Since the sinking of the Titanic, there has been a widespread belief that the social norm of “women and children first” (WCF) gives women a survival advantage over men in maritime disasters, and that captains and crew members give priority to passengers. We analyze a database of 18 maritime disasters spanning three centuries, covering the fate of over 15,000 individuals of more than 30 nationalities. Our results provide a unique picture of maritime disasters. Women have a distinct survival disadvantage compared with men. Captains and crew survive at a significantly higher rate than passengers. We also find that: the captain has the power to enforce normative behavior; there seems to be no association between duration of a disaster and the impact of social norms; women fare no better when they constitute a small share of the ship's complement; the length of the voyage before the disaster appears to have no impact on women's relative survival rate; the sex gap in survival rates has declined since World War I; and women have a larger disadvantage in British shipwrecks. Taken together, our findings show that human behavior in life-and-death situations is best captured by the expression “every man for himself.”
altruism | discrimination | homo economicus | leadership | mortality
The new fossils were all found on the Karari Ridge of Koobi Fora, within 10 kilometers of the fossil beds where the 1470 skull was found-and within the same region where fossils of H. habilis and H. erectus have been discovered. Paleoanthropologist Timothy White of the University of California, Berkeley, warns that the new fossils could be H. habilis because “we still don't understand H. habilis.” But if three species coexisted at roughly the same time and place, says paleoanthropologist William Kimbel of Arizona State University, Tempe, who is not a co-author, “we need to think about hypotheses to explain how they might have divided up their world adaptively.”
The power of weak ties. Mobile-phone records affirm the idea that occasional contacts between casual acquaintances are crucial to the spread of information.
In some instances, big data have showed that long-standing ideas are wrong. This year, Kleinberg and his colleagues used data from the roughly 900 million users of Facebook to study contagion in social networks – a process that describes the spread of ideas such as fads, political opinions, new technologies and financial decisions. Almost all theories had assumed that the process mirrors viral contagion: the chance of a person adopting a new idea increases with the number of believers to which he or she is exposed.
Kleinberg's student Johan Ugander found that there is more to it than that: people's decision to join Facebook varies not with the total number of friends who are already using the site, but with the number of distinct social groups those friends occupy9. In other words, finding that Facebook is being used by people from, say, your work, your sports club and your close friends makes more of an impression than finding that friends from only one group use it. The conclusion – that the spread of ideas depends on the variety of people that hold them – could be important for marketing and public-health campaigns.
The identification of an enzyme in rice that confers improved plant yields on phosphorus-deficient soils could open up new avenues for generating nutrientefficient crops that can thrive on marginally fertile soils.
n488-0471-Supplement1.pdf, n488-0471-Supplement2.xls
Augustine Kong, Michael L. Frigge, Gisli Masson, Soren Besenbacher, Patrick Sulem, Gisli Magnusson, Sigurjon A. Gudjonsson, Asgeir Sigurdsson, Aslaug Jonasdottir, Adalbjorg Jonasdottir, Wendy S. W. Wong, Gunnar Sigurdsson, G. Bragi Walters, Stacy Steinberg, Hannes Helgason, Gudmar Thorleifsson, Daniel F. Gudbjartsson, Agnar Helgason, Olafur Th. Magnusson, Unnur Thorsteinsdottir and Kari Stefansson
Mutations generate sequence diversity and provide a substrate for selection. The rate of de novo mutations is therefore of major importance to evolution. Here we conduct a study of genome-wide mutation rates by sequencing the entire genomes of 78 Icelandic parent-offspring trios at high coverage. We show that in our samples, with an average father's age of 29.7, the average de novo mutation rate is 1.2031028 per nucleotide per generation. Most notably, the diversity in mutation rate of single nucleotide polymorphisms is dominated by the age of the father at conception of the child. The effect is an increase of about two mutations per year. An exponential model estimates paternal mutations doubling every 16.5 years. After accounting for random Poisson variation, father's age is estimated to explain nearly all of the remaining variation in the de novo mutation counts. These observations shed light on the importance of the father's age on the risk of diseases such as schizophrenia and autism.
CO2 capture and storage (CCS) has the potential to develop into an important tool to address climate change. Given society's present reliance on fossil fuels, widespread adoption of CCS appears indispensable for meeting stringent climate targets. We argue that for conventional CCS to become a successful climate mitigation technology-which by necessity has to operate on a large scale-it may need to be complemented with air capture, removing CO2 directly from the atmosphere. Air capture of CO2 could act as insurance against CO2 leaking from storage and furthermore may provide an option for dealing with emissions from mobile dispersed sources such as automobiles and airplanes.
carbon dioxide | negative emissions
In the health and life sciences and many other scientific disciplines, problem solving depends on mathematical skills. However, significant deficiencies are commonly found in this regard in undergraduate students. In an attempt to understand the underlying causes, and to improve students' performances, this article describes a ten-year survey (2000-2010) of mathematical skills of undergraduate Spanish students enrolled on a Plant Physiology course. The results show that the percentage of correct answers decreased for questions requiring some mathematical skills, particularly those needing calculations. Interestingly, percentages of failure do not explain the differences between correct answers for mathematical and nonmathematical questions. These suggest weaknesses in students' mathematical competency and also to a lack of self-efficacy. Additionally, although mathematical questions represented only about 14 % of all the questions and did not show higher discrimination coefficients (0.27 versus 0.29), they were good predictors of the students' final grades.
Keywords: mathematical literacy, numeracy, Plant Physiology, self-efficacy, tertiary education
pnas109-03247-Comment.pdf, pnas109-03247-Reply.pdf
The U.S. Department of Energy has estimated that if the United States is to generate 20 % of its electricity from wind, over 50 GW will be required from shallow offshore turbines. Hurricanes are a potential risk to these turbines. Turbine tower buckling has been observed in typhoons, but no offshore wind turbines have yet been built in the United States. We present a probabilistic model to estimate the number of turbines that would be destroyed by hurricanes in an offshore wind farm.We apply this model to estimate the risk to offshore wind farms in four representative locations in the Atlantic and Gulf Coastal waters of the United States. In the most vulnerable areas now being actively considered by developers, nearly half the turbines in a farm are likely to be destroyed in a 20-y period. Reasonable mitigation measures—increasing the design reference wind load, ensuring that the nacelle can be turned into rapidly changing winds, and building most wind plants in the areas with lower risk—can greatly enhance the probability that offshore wind can help to meet the United States' electricity needs.
probabilistic analysis | wind energy | phase-type distribution | tropical cyclone
Carbon dioxide may be the ultimate industrial waste product. Could tropical corals provide a trick for locking it away in our highways?
Francesco d'Errico, Lucinda Backwell, Paola Villa, Ilaria Degano, Jeannette J. Lucejko, Marion K. Bamford, Thomas F. G. Higham, Maria Perla Colombini and Peter B. Beaumont
Recent archaeological discoveries have revealed that pigment use, beads, engravings, and sophisticated stone and bone tools were already present in southern Africa 75,000 y ago. Many of these artifacts disappeared by 60,000 y ago, suggesting that modern behavior appeared in the past and was subsequently lost before becoming firmly established. Most archaeologists think that San hunter-gatherer cultural adaptation emerged 20,000 y ago. However, reanalysis of organic artifacts from Border Cave, South Africa, shows that the Early Later Stone Age inhabitants of this cave used notched bones for notational purposes,wooden digging sticks, bone awls, and bone points similar to those used by San as arrowheads. A point is decorated with a spiral groove filled with red ochre, which closely parallels similar marks that San make to identify their arrowheads when hunting. A mixture of beeswax, Euphorbia resin, and possibly egg, wrapped in vegetal fibers, dated to 40,000 BP, may have been used for hafting. Ornaments include marine shell beads and ostrich eggshell beads, directly dated to 42,000 BP. A digging stick, dated to 39,000 BP, is made of Flueggea virosa. A wooden poison applicator, dated to 24,000 BP, retains residueswith ricinoleic acid, derived from poisonous castor beans. Reappraisal of radiocarbon age estimates through Bayesian modeling, and the identification of key elements of San material culture at Border Cave, places the emergence of modern hunter-gatherer adaptation, as we know it, to 44,000 y ago.
bone artifacts | chemical analysis | modernity | wooden artifacts
Paola Villa, Sylvain Soriano, Tsenka Tsanova, Ilaria Degano, Thomas F. G. Higham, Francesco d'Errico, Lucinda Backwell, Jeannette J. Lucejko, Maria Perla Colombini and Peter B. Beaumont
The transition from the Middle Stone Age (MSA) to the Later Stone Age (LSA) in South Africa was not associated with the appearance of anatomically modern humans and the extinction of Neandertals, as in the Middle to Upper Paleolithic transition in Western Europe. It has therefore attracted less attention, yet it provides insights into patterns of technological evolution not associated with a new hominin. Data from Border Cave (KwaZulu-Natal) show a strong pattern of technological change at approximately 44-42 ka cal BP, marked by adoption of techniques and materials that were present but scarcely used in the previous MSA, and some novelties. The agent of change was neither a revolution nor the advent of a new species of human. Although most evident in personal ornaments and symbolic markings, the change from one way of living to another was not restricted to aesthetics. Our analysis shows that: (i) at Border Cave two assemblages, dated to 45-49 and >49 ka, show a gradual abandonment of the technology and tool types of the post-Howiesons Poort period and can be considered transitional industries; (ii) the 44-42 ka cal BP assemblages are based on an expedient technology dominated by bipolar knapping, with microliths hafted with pitch from Podocarpus bark, worked suid tusks, ostrich eggshell beads, bone arrowheads, engraved bones, bored stones, and digging sticks; (iii) these assemblages mark the beginning of the LSA in South Africa; (iv) the LSA emerged by internal evolution; and (v) the process of change began sometime after 56 ka.
human behavior | hafting pitch | hunting weapons | gathering equipment
This paper focuses on the impacts of rapid climate change (RCC) and climate forcing in the course of the last six centuries of the seventh millennium cal BC in the eastern Mediterranean. Against the background of earlier ethnographic studies in West Africa which have highlighted coping strategies among semi-nomadic Kel Ewey-Tuareg, the archaeology of two neolithic settlements, Tell Sabi Abyad in northern Syria and Mersin-Yumuktepe on the Mediterranean coast of southern Turkey, is reassessed. Both these settlements have in common an uninterrupted sequence of occupation for the entire duration of a rapid climate change (RCC) interval between 8,6-8,0 ka cal BP. It is proposed that contemporaneous developments observed at these sites, which include, for example, fluctuation in the intensity of occupation, possible (burned) destruction levels, and the introduction of (centralised) collective storage, may be associated with reactions of Late Neolithic – Early Chalcolithic communities to climate change.
Dieser Beitrag befasst sich mit den Auswirkungen von ¢Rapid-Climate-Changeï (RCC) in den letzten sechs Jahrhunderten des siebten Jahrtausends cal BC im östlichen Mittelmeerraum. In Anbetracht ethnograischer Studien zu den Bewältigungsstrategien (¢Coping Strategiesï) von halbnomadischen Tuareg in Westafrika werden die durch archäologische Untersuchungen an zwei neolithischen Siedlungsplätzen gewonnenen Erkenntnisse einer Neueinschätzung unterzogen. Tell Sabi Abyad in Nordsyrien und Mersin-Yumuktepe an der südtürkischen Mittelmeerküste weisen eine durchgehende Besiedlung für die gesamte Zeitspanne des RCC-intervalls von 8,6 ka bis 8,0 ka cal BP auf. Es wird postuliert, dass gleichzeitige Entwicklungen wie sie sich an diesen beiden Siedlungen nachweisen lassen – z. B. Schwankungen in der Besiedlungsintensität, das Auftreten von Zerstörungshorizonten sowie die Einführung einer möglicherweise zentral geregelten Vorratshaltung – mit Reaktionen spätneolithischer und frühchalkolithischer Gesellschaften auf die Klimaveränderung in Zusammenhang stehen könnten.
Temperature reconstructions from the deep sea reveal how the global ice volume has varied over the past 1.5 million years.
s337-0704-Supplement1.pdf, s337-0704-Supplement2.xlsx
Earth's climate underwent a fundamental change between 1250 and 700 thousand years ago, the mid-Pleistocene transition (MPT), when the dominant periodicity of climate cycles changed from 41 thousand to 100 thousand years in the absence of substantial change in orbital forcing. Over this time, an increase occurred in the amplitude of change of deep-ocean foraminiferal oxygen isotopic ratios, traditionally interpreted as defining the main rhythm of ice ages although containing large effects of changes in deep-ocean temperature. We have separated the effects of decreasing temperature and increasing global ice volume on oxygen isotope ratios. Our results suggest that the MPT was initiated by an abrupt increase in Antarctic ice volume 900 thousand years ago. We see no evidence of a pattern of gradual cooling, but near-freezing temperatures occur at every glacial maximum.
All estimates of British income per caput show a robust growth from 1770 to 1850, as do widely cited measures of real wages for most occupations. With even a modest income elasticity of demand for food, these income and wage measures imply a substantial growth in food demand per person. Yet when we look at the supply of foodstuffs, here meaning the food materials generated by domestic farm production and by net imports, a puzzle appears. Three different methods of estimating foodstuff supplies per caput show that these stagnated or even declined. This is the food puzzle.
The source of this contradiction lies with at least one of three suspects: either the foodstuff supply estimates are wrong, or rising incomes failed to raise food demands as predicted by past studies of Engel's Law, or incomes did not rise. We try the first two suspects directly, and judge the third in absentia. The estimates of income growth will be handed a preliminary indictment if we can find no fault in either the estimates of foodstuff supplies or the conventional use of income elasticities.
I use building workers' wages for 1209-2004 and the skill premium to consider the causes and consequences of the Industrial Revolution. Real wages were trendless before 1800, as would be predicted for the Malthusian era. Comparing wages with population, however, suggests that the break from the technological stagnation of the Malthusian era came around 1640, long before the classic Industrial Revolution, and even before the arrival of modern democracy in 1689. Building wages also conflict with human capital interpretations of the Industrial Revolution, as modeled by Gary Becker, Kevin Murphy, and Robert Tamura; Oded Galor and David Weil; and Robert Lucas. Human capital accumulation began when the rewards for skills were unchanged and when fertility was increasing.
Why are some parts of the world so rich and others so poor? Why did the Industrial Revolution—and the unprecedented economic growth that came with it—occur in eighteenth-century England, and not at some other time, or in some other place? Why didn't industrialization make the whole world rich—and why did it make large parts of the world even poorer? In A Farewell to Alms, Gregory Clark tackles these profound questions and suggests a new and provocative way in which culture—not exploitation, geography, or resources—explains the wealth, and the poverty, of nations.
Countering the prevailing theory that the Industrial Revolution was sparked by the sudden development of stable political, legal, and economic institutions in seventeenth-century Europe, Clark shows that such institutions existed long before industrialization. He argues instead that these institutions gradually led to deep cultural changes by encouraging people to abandon hunter-gatherer instincts—violence, impatience, and economy of effort—and adopt economic habits—hard work, rationality, and education.
The problem, Clark says, is that only societies that have long histories of settlement and security seem to develop the cultural characteristics and effective workforces that enable economic growth. For the many societies that have not enjoyed long periods of stability, industrialization has not been a blessing. Clark also dissects the notion, championed by Jared Diamond in Guns, Germs, and Steel, that natural endowments such as geography account for differences in the wealth of nations.
A brilliant and sobering challenge to the idea that poor societies can be economically developed through outside intervention, A Farewell to Alms may change the way global economic history is understood.
The article forms three series for English farm workers from 1209-1869: nominal day wages, the implied marginal product of a day of farm labour, and the purchasing power of a day's wage in terms of farm workers' consumption. These series suggest that labour productivity in English agriculture was already high in the middle ages. Furthermore, they fit well with one method of estimating medieval population that suggests a peak English population c. 1300 of nearly 6 million. Lastly, they imply that both agricultural technology and the general efficiency of the economy were static from 1250 till 1600. Economic changes were in these years entirely a product of demographic shifts. From 1600 to 1800, technological advance in agriculture provided an alternative source of dynamism in the English economy.
ProcRSocB2012-preprint-Supplement1.doc, ProcRSocB2012-preprint-Supplement2.xls, ProcRSocB2012-preprint-Supplement3.doc
Adaptive accounts of modern low human fertility argue that small family size maximizes the inheritance of socioeconomic resources across generations and may consequently increase long-term fitness. This study explores the long-term impacts of fertility and socioeconomic position (SEP) on multiple dimensions of descendant success in a unique Swedish cohort of 14 000 individuals born during 1915-1929. We show that low fertility and high SEP predict increased descendant socioeconomic success across four generations. Furthermore, these effects are multiplicative, with the greatest benefits of low fertility observed when SEP is high. Low fertility and high SEP do not, however, predict increased descendant reproductive success. Our results are therefore consistent with the idea that modern fertility limitation represents a strategic response to the local costs of rearing socioeconomically competitive offspring, but contradict adaptive models suggesting that it maximizes long-term fitness. This indicates a conflict in modern societies between behaviours promoting socioeconomic versus biological success. This study also makes a methodological contribution, demonstrating that the number of offspring strongly predicts long-term fitness and thereby validating use of fertility data to estimate current selective pressures in modern populations. Finally, our findings highlight that differences in fertility and SEP can have important long-term effects on the persistence of social inequalities across generations.
Keywords: demographic transition; multigenerational; fertility; socioeconomic position; reproductive success; quality-quantity trade-off
So-called control mechanisms as a basis of social power shall be compared in four societies in Europe and Asia which were in coexistence during the middle and later 3rd millennium BC. While in some cases (southern Mesopotamia) we have good indications for social power operating largely from above, such notions cannot easily be adduced from the archaeological record in other regions (Indus Valley, Aegean), in which there were possibly many different levels on which social power was exercised on an everyday basis. Finally, in the fourth region (Bell Beaker Central Europe) it is hard to recognise not only clear signs of social power, but also any possible basis for distinctions in social power. It will be argued that the establishment of control mechanisms was fundamental to achieve institutionalized and long-term inequality in the societies discussed in this article. The adoption of such control mechanisms enabled a group of people (the elite) to regulate and hence dominate resources. Some of the best archaeological indications are writing, the practice of sealing and the invention and standardisation of metrological systems. The open question is how many members of the given society were able to participate in the regulation of power. The archaeological indications often do not imply a strongly hierarchical society, or a society where a single person (king or chief) and/or his clique could dominate. Instead the archaeological record points to flexible and fluctuating power relations. Therefore, it is argued that some early complex societies of the second half of the 3rd millennium BC (like Greece or the Indus Valley) can be better described as heterarchical than hierarchical. For prehistoric Europe it is argued that social power was highly fluid and that no long-term systematization of power relations is traceable before the Iron Age (and even then it is often debatable). Therefore, any claim for the existence of simple or complex chiefdoms in prehistoric Europe (outside the Aegean) during the Copper and Bronze Age seems to be misleading.
Race, Monogamy, and Other Lies They Told You. Busting Myths About Human Nature. by Agustín Fuentes. University of California Press, Berkeley, 2012. 290 pp. $27.50, £19.95. ISBN 9780520269712.
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