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John Bohannon, Fight over author pseudonyms could flare again. science 351 (2016), 902.
Editor balks at authors using screen names from RNA folding game.
A JMB editor was concerned about some of the co-authors’ names. Rather than using their real-world identities, they had given only the screen handles under which they had done the research within Eterna, a massive online game that crowdsources RNA folding problems.
Ewen Callaway, Ancient DNA pinpoints dawn of Neanderthals. nature 531 (2016), 286.
Sequencing of 430,000-year-old DNA pushes back species’ divergence from humans.
The nuclear DNA, Meyer’s team reports in Nature on 14 March, shows that the Sima hominins are in fact early Neanderthals. And its age suggests that the early predecessors of humans diverged from those of Neanderthals between 550,000 and 765,000 years ago — too far back for the common ancestors of both to have been Homo heidelbergensis, as some had posited. Researchers should now be looking for a population that lived around 700,000 to 900,000 years ago, says Martinón-Torres. She thinks that Homo antecessor, known from 900,000-year-old remains from Spain, is the strongest candidate for the common ancestor, if such specimens can be found in Africa or the Middle East.
France A. Córdova, Embrace uncertainty. science 351 (2016), 994.
Don’t spend more time than you need to in graduate school. It may seem fun to be a student, or scary to figure out next steps, but you will have greater responsibility and freedom (and get paid more) after you graduate, so get a postgraduation plan together. You can’t go wrong if you choose the one that resonates with you the most. Try not to make decisions based solely on money, especially early in your career, when salaries tend to be at their lowest. In summary, don’t fear decisions; embrace them. They allow you to explore new ideas and places. They mark the pathways that make your journey unique. Your choices will define you, so my last piece of advice is simple: Be yourself. You can’t make a bad choice if you remain true to yourself.
Eli Kintisch, Arctic shipworm discovery alarms archaeologists. science 351 (2016), 901.
Sunken log full of tunneling mollusks poses mystery.
The researchers were astonished because shipworms—mollusks adapted to tunnel into and eat wood—had never been documented so far north, just 1100 kilometers from the North Pole, and at such a depth, where the temperature was –1.8°C.
Dennis Normile, Nature from Nurture. science 351 (2016), 908–910.
As Japan’s rice paddies go fallow, biodiversity suffers—raising questions about rewilding strategies the world over.
Early Japanese, like many primitive peoples, periodically set fires to create and maintain grasslands that first made hunting easier and later provided fodder for livestock. The scorched landscape paved the way for colonizing plants. Later, as rice cultivation displaced the seminatural grasslands, those plants and their dependent insects and birds adapted to thrive in the paddy environment.
As more such paddies across Japan are abandoned, he says, many rare plants and insects that have coexisted with Japanese farming for millennia, including the sunflower relative (the yaburegasamodoki), are likely to follow traditional farmers into extinction.
Fernando Rosario-Ortiz, Joan Rose, Vanessa Speight, Urs von Gunten & Jerald Schnoor, How do you like your tap water? science 351 (2016), 912–914.
Safe drinking water may not need to contain a residual disinfectant.
In the Netherlands, at least half of the water distribution pipes have been replaced since the 1970s; as a result, pipe networks are, on average, 33 to 37 years old. Although there are regional differences, an estimated 22 % of the pipes in the United States are more than 50 years old; the average age of pipe at failure is 47 years, and only 43 % of pipes are considered to be in good or excellent condition.
Oliver Schilke, Martin Reimann & Karen S. Cook, Power, whether situational or durable, decreases both relational and generalized trust, Reply to Wu and Wilkes. PNAS 113 (2016), E1418.
Results revealed a significant negative correlation, Pearson’s r = -0.094, P = 0.030, d = -0.190, suggesting that the negative power–trust effect reported in our article generalizes to more durable conceptualizations of both constructs.
Dominick V. Spracklen, China’s contribution to climate change. nature 531 (2016), 310–312.
Carbon dioxide emissions from fossil-fuel use in China have grown dramatically in the past few decades, yet it emerges that the country’s relative contribution to global climate change has remained surprisingly constant.
It has long been known that some air pollutants cool the climate2; what is remarkable in the present study is that the concurrent changes in different emissions have led to a stable overall contribution of China to global radiative forcing. This means that it will be difficult to achieve rapid reductions in near-term global warming through the control of Chinese air pollutants overall.
Cary Wu & Rima Wilkes, Durable power and generalized trust in everyday social exchange. PNAS 113 (2016), E1417.
The first caveat is that, instead of concluding that power-holders trust less, it is more appropriate to say that power-holders are less dependent on trust in exchange relationships.
Participants who are assigned to a highpower position have more attractive alternatives and, as a result, do not need to trust their exchange partners. However, this finding may not hold outside of experimental and specific exchange relationships and in cases where power is more enduring. At the broader societal level, social scientists have shown that powerful “haves” are more trusting than lesspowerful “have-nots”. The source of this power imbalance is not a temporary role assigned during an experiment but the enduring and lived experience of privilege and inequality. Power decreases the cost of risk-taking, and therefore enables those with power to trust more.
Clayton R. Magill, Gail M. Ashley, Manuel Domínguez-Rodrigo & Katherine H. Freeman, Dietary options and behavior suggested by plant biomarker evidence in an early human habitat. PNAS 113 (2016), 2874–2879.
The availability of plants and freshwater shapes the diets and social behavior of chimpanzees, our closest living relative. However, limited evidence about the spatial relationships shared between ancestral human (hominin) remains, edible resources, refuge, and freshwater leaves the influence of local resources on our species’ evolution open to debate. Exceptionally well-preserved organic geochemical fossils—biomarkers—preserved in a soil horizon resolve different plant communities at meter scales across a contiguous 25,000 m2 archaeological land surface at Olduvai Gorge from about 2 Ma. Biomarkers reveal hominins had access to aquatic plants and protective woods in a patchwork landscape, which included a spring-fed wetland near a woodland that both were surrounded by open grassland. Numerous cut-marked animal bones are located within the wooded area, and within meters of wetland vegetation delineated by biomarkers for ferns and sedges. Taken together, plant biomarkers, clustered bone debris, and hominin remains define a clear spatial pattern that places animal butchery amid the refuge of an isolated forest patch and near freshwater with diverse edible resources.
Keywords: biomarker | leaf wax | carbon isotope | paleoecology | human evolution
Significance: Humans evolved in response to the availability of plant and water resources over space and through time. Their influence on our species’ evolution is debated, though, because archives of their spatial distribution are scarce at early human (hominin) localities. Meter-scale vegetation patterns are revealed from sedimentary plant biomarkers across an archaeological horizon at Olduvai Gorge (FLK Zinj). Biomarkers evince a varied local landscape with a woodland patch near a small freshwater wetland, surrounded by an open grassland landscape. Biomarkers from the wetland indicate diverse edible plants near potable water. The coexistence of butchered large animal bones and hominin remains, including juveniles, within an isolated biomarkerdelineated wooded microhabitat at FLK Zinj provide support for early provisioning behaviors by our ancestors.
Hania Luczak, Wenn Hunger zum Freund wird. Geo 2016 , iii, 30–45.
Fasten ist viel mehr als nicht essen. Es ist universeller Bestandteil der menschlichen Natur und Kultur. Weltweit dringen Forscher vor zu den geheimnisvollen Wirkungsweisen des freiwilligen Nahrungsverzichts – und finden erstaunliehe Heileffekte. Ob drei Wochen lang oder fünf Tage oder nur 16 Stunden am Stück – lange Pausen zwischen den Mahlzeiten verjüngen nicht nur den Körper, sie sollen sogar bei Demenz und Krebs Wirkung zeigen
Martin Street & Olaf Jöris, Das Alter der Funde von Bonn-Oberkassel. In: Landesmuseum Bonn (Hrsg.), Eiszeitjäger. Leben im Paradies? Europa vor 15 000 Jahren. (Mainz 2014), 182–189.
Erik Stokstad, Power Play on the Nile. science 351 (2016), 904–907.
Ethiopia stunned neighbors with a colossal dam on the Blue Nile. Could it spread prosperity, not turmoil?
Shumon T. Hussain, Mensch, Fluss und Raum, Überlegungen zur ökokulturellen Rolle grosser Flusssysteme im europäischen Jungpaläolithikum. Archäologisches Korrespondenzblatt 45 (2015), 439–458.
Large river axes constitute important spatial thresholds in the European Upper Palaeolithic. In these glacial landscapes, rivers typically represent elements of high focality. Rivers are particularly relevant for human spatial organisation because they create unique affordances and heuristics, thereby enabling the convergence of “natural spaces” and “cultural spaces”. In the early (Aurignacian) and the late Upper Palaeolithic (Magdalenian), this spatial matrix is reflected in the use of river systems as axes of mobility and communication. The accessibility and prominence of these river systems coincides with the socio-historical background of colonisation and a limited landscape knowledge. By contrast, it seems possible to distinguish a phase in the middle Upper Palaeolithic (Gravettian), during which rivers regularly assume frontier or boundary functions and thereby reproduce the heterogeneity of the social space. In this context, river focality meets a cultural-geographic consolidation background comprising accumulated and readily available landscape knowledge.
Keywords: Europe / Palaeolithic / Ice Age / spatial theory / symmetry / mobility / exchange
Im europäischen Jungpaläolithikum müssen große Flussachsen als wichtige Konstitutivgrößen menschlicher Räumlichkeit verstanden werden. Glaziale Flüsse repräsentieren in diesen Landschaften typischerweise Elemente hoher Fokalität, die sich durch die Hervorbringung spezifischer Affordanzen und Heuristiken für die menschliche Raumnutzung als besonders relevant erweisen und so eine Konvergenz von Natur- und Kulturraum begünstigen. Im frühen (Aurignacien) und späten Jungpaläolithikum (Magdalénien) schlägt sich diese Matrix in der Nutzung von Flusssystemen als Mobilitätsund Kommunikationsachsen nieder. In diesen Kontexten fällt die Zugänglichkeit und Prominenz großer Flussläufe mit einem sozialhistorischen Kolonisationshintergrund und begrenztem Landschaftswissen zusammen. Demgegenüber lässt sich ein Abschnitt im mittleren Jungpaläolithikum (Gravettien) unterscheiden, in dem Flüsse häufiger Grenzfunktionen annehmen und dabei die heterogene Struktur des sozialen Raums abbilden. Der Fokalität von Flusssystemen kann dort demgemäß ein kulturgeographischer Konsolidierungshintergrund mit “gewachsenem” und hinreichend verfügbarem Landschaftswissen gegenübergestellt werden.
Keywords: Europa / Paläolithikum / Eiszeit / Raumtheorie / Symmetrie / Mobilität / Austausch
Martin Street & Olaf Jöris, The age of the Oberkassel burial in the context of climate, environment and the late glacial settlement history of the Rhineland. In: Liane Giemsch & Ralf Schmitz (Hrsg.), The Late Glacial Burial from Oberkassel Revisited. Rheinische-Ausgrabungen 72 (Bonn 2015), 25–42.
The character, quantity and nutritional potential of the fauna available to humans as a food source clearly have major implications for the conscious and unconscious choices they must make to ensure survival. The successful change from the steppebased subsistence strategy of Magdalenian humans to that of the later wooded interstadial is clearly demonstrated at the Backed-Point Group sites of the Neuwied Basin; however, the poor evidence for the intermediate period mean that the timing and nature of this change remain unknown.
The probable age of the Oberkassel burial in the second half of GI 1e marks a time when the irst growth of interstadial woodland had reached a maximum, before then being killed off by a severe fall in temperature during GI 1d. These were events that could be observed within a human lifetime and it might be considered whether either or both of these two factors—the gradual increase of woodland cover and its sudden destruction—could have had a major inluence on the life and death of the Oberkassel man and woman.
Robert E. Kopp et al., Temperature-driven global sea-level variability in the Common Era. PNAS 113 (2016), E1434–E1441.
pnas113-E1434-Supplement2.xls, pnas113-E1434-Supplement3.xls
Robert E. Kopp, Andrew C. Kemp, Klaus Bittermann, Benjamin P. Horton, Jeffrey P. Donnelly, W. Roland Gehrels, Carling C. Hay, Jerry X. Mitrovica, Eric D. Morrow & Stefan Rahmstorf
We assess the relationship between temperature and global sealevel (GSL) variability over the Common Era through a statistical metaanalysis of proxy relative sea-level reconstructions and tidegauge data. GSL rose at 0.1 ± 0.1 mm/y (2s) over 0–700 CE. A GSL fall of 0.2 ± 0.2 mm/y over 1000–1400 CE is associated with 0.2 °C global mean cooling. A significant GSL acceleration began in the 19th century and yielded a 20th century rise that is extremely likely (probability P ≥ 0.95) faster than during any of the previous 27 centuries. A semiempirical model calibrated against the GSL reconstruction indicates that, in the absence of anthropogenic climate change, it is extremely likely (P = 0.95) that 20th century GSL would have risen by less than 51 % of the observed 13.8 ± 1.5 cm. The new semiempirical model largely reconciles previous differences between semiempirical 21st century GSL projections and the process model-based projections summarized in the Intergovernmental Panel on Climate Change’s Fifth Assessment Report.
Keywords: sea level | Common Era | late Holocene | climate | ocean
Significance: We present the first, to our knowledge, estimate of global sea-level (GSL) change over the last 3,000 years that is based upon statistical synthesis of a global database of regional sea-level reconstructions. GSL varied by ±8 cm over the pre-Industrial Common Era, with a notable decline over 1000–1400 CE coinciding with 0.2 °C of global cooling. The 20th century rise was extremely likely faster than during any of the 27 previous centuries. Semiempirical modeling indicates that, without global warming, GSL in the 20th century very likely would have risen by between 3 cm and +7 cm, rather than the 14 cm observed. Semiempirical 21st century projections largely reconcile differences between Intergovernmental Panel on Climate Change projections and semiempirical models.
Bengang Li et al., The contribution of China’s emissions to global climate forcing. nature 531 (2016), 357–361.
n531-0357-Supplement1.pdf, n531-0357-Supplement2.zip
Bengang Li, Thomas Gasser, Philippe Ciais, Shilong Piao, Shu Tao, Yves Balkanski, Didier Hauglustaine, Juan-Pablo Boisier, Zhuo Chen, Mengtian Huang, Laurent Zhaoxin Li, Yue Li, Hongyan Liu, Junfeng Liu, Shushi Peng, Zehao Shen, Zhenzhong Sun, Rong Wang, Tao Wang, Guodong Yin, Yi Yin, Hui Zeng, Zhenzhong Zeng & Feng Zhou
Knowledge of the contribution that individual countries have made to global radiative forcing is important to the implementation of the agreement on “common but differentiated responsibilities” reached by the United Nations Framework Convention on Climate Change. Over the past three decades, China has experienced rapid economic development1, accompanied by increased emission of greenhouse gases, ozone precursors and aerosols2,3, but the magnitude of the associated radiative forcing has remained unclear. Here we use a global coupled biogeochemistry–climate model4,5 and a chemistry and transport model6 to quantify China’s present-day contribution to global radiative forcing due to well-mixed greenhouse gases, short-lived atmospheric climate forcers and land-use-induced regional surface albedo changes. We find that China contributes 10 % ± 4 % of the current global radiative forcing. China’s relative contribution to the positive (warming) component of global radiative forcing, mainly induced by well-mixed greenhouse gases and black carbon aerosols, is 12 % ± 2 %. Its relative contribution to the negative (cooling) component is 15 % ± 6 %, dominated by the effect of sulfate and nitrate aerosols. China’s strongest contributions are 0.16 ± 0.02 watts per square metre for CO2 from fossil fuel burning, 0.13 ± 0.05 watts per square metre for CH4, -0.11 ± 0.05 watts per square metre for sulfate aerosols, and 0.09 ± 0.06 watts per square metre for black carbon aerosols. China’s eventual goal of improving air quality will result in changes in radiative forcing in the coming years: a reduction of sulfur dioxide emissions would drive a faster future warming, unless offset by larger reductions of radiative forcing from well-mixed greenhouse gases and black carbon.
Maxime Derex & Robert Boyd, Partial connectivity increases cultural accumulation within groups. PNAS 113 (2016), 2982–2987.
Complex technologies used in most human societies are beyond the inventive capacities of individuals. Instead, they result from a cumulative process in which innovations are gradually added to existing cultural traits across many generations. Recent work suggests that a population’s ability to develop complex technologies is positively affected by its size and connectedness. Here, we present a simple computer-based experiment that compares the accumulation of innovations by fully and partially connected groups of the same size in a complex fitness landscape. We find that the propensity to learn from successful individuals drastically reduces cultural diversity within fully connected groups. In comparison, partially connected groups produce more diverse solutions, and this diversity allows them to develop complex solutions that are never produced in fully connected groups. These results suggest that explanations of ancestral patterns of cultural complexity may need to consider levels of population fragmentation and interaction patterns between partially isolated groups.
Keywords: cultural evolution | innovation | population size | social network | technological trajectory
Significance: The remarkable ecological success of the human species has been attributed to our capacity to overcome environmental challenges through the development of complex technologies. Complex technologies are typically beyond the inventive capacities of individuals and result from a population process by which innovations are gradually added to existing cultural traits across many generations. Recent work suggests that a population’s ability to develop technologies is positively affected by its size and connectedness. Here, we present an experiment demonstrating that partially connected groups produce more diverse and complex cultural traits than fully connected groups. This result suggests that changes in patterns of interaction between human groups may have created propitious conditions for the emergence of complex cultural repertoires in our evolutionary past.
Svend Hansen, Krieg in der Bronzezeit. In: Harald Meller & Michael Schefzik (Hrsg.), Krieg – Eine Archäologische Spurensuche, Begleitband zur Sonderausstellung im Landesmuseum für Vorgeschichte Halle (Saale), 6. November 2015 bis 22. Mai 2016. (Halle 2015), 205–212.
Ehre und Ruhm gehörten, so dürfen wir unterstellen, zum kulturellen Code der Mächtigen in der Bronzezeit. Die Ideologie des Heldischen ist aber nicht erst im 2o. Jh. infrage gestellt, sondern schon früh kritisiert worden, sicher auch weit bevor es die ersten Texte belegen. C. Alexander (2oo9) hat die “Ilias” einer postheroischen Lektüre unterzogen und dabei aufgedeckt, wie illusionslos die heroische Sicht des Krieges auch im Epos in Zweifel gezogen und letztlich dessen totale Sinnlosigkeit sichtbar gemacht wurde. Deshalb stand der griechische Dichter Archilochos im 7. Jh.v.Chr. wohl keineswegs im gesellschaftlichen Abseits, wenn er in einem Gedicht bekannte, wenig heldenhaft seinen Schutzschild im Dickicht verloren, aber dafür sein Leben gerettet zu haben.
Die Archäologie der Bronzezeit verfügt über einen Fundus von Quellen, die auf den verschiedensten Ebenen einen Einblick in die Realität der Gewalt dieser Zeit vermitteln. Damit leistet sie auch einen Beitrag zu den bedrückend aktuellen Fragen des Krieges und der Gewalt. Allein die prähistorische Archäologie vermag die Geschichte der letzten 1o ooo Jahre zu schreiben, mit einem natürlich eingeschränkten Quellenmaterial, wie dies für jede historische Wissenschaft charakteristisch ist. In den letzten Jahren sind für die Gewaltgeschichte bedeutende Funde auf methodisch höchstem Niveau untersucht worden. Das Ziel ist, eine möglichst genaue historische Verortung kriegerischer Gewalt und eine Abschätzung ihrer Dimensionen zu leisten und somit einen Beitrag zu einer Betrachtung zu liefern, die Gewalt als ein soziales und politisches, also nicht nur individuelles Phänomen versteht.
Konstantinos Tsetsos, Rani Moran, James Moreland, Nick Chater, Marius Usher & Christopher Summerfield, Economic irrationality is optimal during noisy decision making. PNAS 113 (2016), 3102–3107.
According to normative theories, reward-maximizing agents should have consistent preferences. Thus, when faced with alternatives A, B, and C, an individual preferring A to B and B to C should prefer A to C. However, it has been widely argued that humans can incur losses by violating this axiom of transitivity, despite strong evolutionary pressure for reward-maximizing choices. Here, adopting a biologically plausible computational framework, we show that intransitive (and thus economically irrational) choices paradoxically improve accuracy (and subsequent economic rewards) when decision formation is corrupted by internal neural noise. Over three experiments, we show that humans accumulate evidence over time using a “selective integration” policy that discards information about alternatives with momentarily lower value. This policy predicts violations of the axiom of transitivity when three equally valued alternatives differ circularly in their number of winning samples. We confirm this prediction in a fourth experiment reporting significant violations of weak stochastic transitivity in human observers. Crucially, we show that relying on selective integration protects choices against “late” noise that otherwise corrupts decision formation beyond the sensory stage. Indeed, we report that individuals with higher late noise relied more strongly on selective integration. These findings suggest that violations of rational choice theory reflect adaptive computations that have evolved in response to irreducible noise during neural information processing.
Keywords: decision making | irrationality | choice optimality | selective integration | evidence accumulation
Significance: Healthy individuals appear to display inconsistent preferences, preferring A over B, B over C, and C over A. Inconsistent, intransitive preferences of this form are hallmark manifestations of irrational choice behavior and breach the very assumptions of economic theory. Nevertheless, the neurocognitive mechanisms that mediate the formation of intransitive preferences remain elusive. We show that intransitivity arises from a bottleneck mechanism that blocks the processing of momentarily less valuable information. Although this algorithm is by classical definitions suboptimal (permitting the loss of information), we theoretically and empirically demonstrate that it leads to better decisions when accuracy can be compromised by neural noise beyond the sensory stage. Thus, contrary to common belief, choice irrationality is a by-product of purposeful neural computations.
David Killick & Thomas Fenn, Archaeometallurgy, The Study of Preindustrial Mining and Metallurgy. Annual Review of Anthropology 41 (2012), 559–575.
Archaeometallurgy is an interdisciplinary and international field of study that examines all aspects of the production, use, and consumption of metals from 8000 BCE to the present, although this review is restricted to mining and metallurgy in preindustrial societies. Most of this literature was not written with an anthropological readership in mind, but many of its central themes are relevant to some current debates in anthropology. Since the 1970s, archaeometallurgists have been concerned explicitly with the materiality of metals and also with the highly variable value of precious metals across time and space. Exacting criteria have been developed for distinguishing past technology transfers from independent inventions. Archaeometallurgists have also done important work on the social construction of technology in precapitalist economies. In short, archaeometallurgy offers much that is of interest to anthropologists who study the growth and spread of knowledge, and of systems of value, before the capitalist era.
Keywords: technology | innovation | materiality | production | exchange | archaeology
Yair Sapir & Avraham Faust, Utilizing Mole-Rat Activity for Archaeological Survey, A Case Study and a Proposal. Advances in Archaeological Practice 4 (2016), 55–70.
Identifying previously unknown sites is a fundamental goal of the archaeological inquiry. In this article, after reporting the results of our work at Tel ‘Eton (Israel), we propose a new method that can increase the effectiveness of surveys. As part of a study of site formation processes, molehills (mole-rat back-dirt hills) were systematically sifted at Tel ‘Eton and its surroundings. It was apparent that the number and size of sherds in molehills on the mound greatly exceeded those found in its surroundings. The incidental identiication of many sherds in molehills northwest of the mound, therefore, led us to suspect that this area was settled. This was tested by transecting the area. The inds, along with discoveries in the wadis cutting the plain, support this suggestion and allowed us to detect the lower city’s boundary. An examination of the site’s environments, moreover, enabled us to identify additional anomalies, like the co-occurrence of concentrations of sherds, red-soiled molehills, and slags, which might indicate an extra-mural workshop. Consequently, we suggest that a systematic examination of rodents’ back-dirt mounds can be an effective method—faster, cheaper, and more eficient than pedestrian surveys or shovel tests—of discovering unknown sites even in regions with good visibility.
Fred Langer, Ein anderer Jesus. Geo 2016 , iv, 52–65.
Was die Bibel verschweigt. Eine verschollene Stadt. Eine verbotene Sehrift. Eine Kirche der Frauen.
Ostern, der Mythos von Kreuzigung und Auferstehung – so stellt es geschrieben. Aber da war noch sehr viel mehr. An den Ursprüngen des Christentums blühte eine spirituelle Welt von faszinierender Vielfalt. Es lohnt sich, diese längst versunkene Kultur der Glaubensfreiheit neu zu entdecken. Gerade jetzt in Zeiten wachsender religiöser Intoleranz.
\cjRL{mrdky qmr.t – ’dwwyn smw’l}, \cjRL{+sArA+siym; mlwn ’.tymwlwgy ‘mmy ‘bry–’ngly}, Roots: a Hebrew–English Word-List by Mordechai Kamrat & Edwin Samuel. (Jerusalem 31972).
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