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Ann Gibbons, Hadza on the Brink. science 360 (2018), 700–704.
Farmers, tourists, and cattle threaten some of the world’s last hunter-gatherers, long a magnet for researchers.
The Datoga are also moving in, building bomas—mud-walled huts encircled by acacia-thorn fences that contain livestock at night—near water sources. The settlements keep the nonconfrontational Hadza and their prey away from the water. “You can see from Google Earth where Datoga bomas are and how the Hadza—especially the women—adjust their spatial behavior to avoid them,” Wood says.
The tourism has a toxic impact. In the roughly 3 weeks that ecological anthropologist Haruna Yatsuka of Nihon University in Mishima, Japan, was in a tourist camp in Mangola in 2013, 40 tourist parties came from 19 nations. She observed the most destructive impact as soon as the tourists left in midafternoon, when the Hadza used their earnings to buy alcohol. “Everybody drinks: pregnant women, breastfeeding women, the men,” says Monika Abels, a developmental psychologist at Tilburg University in the Netherlands, who compared child development between a tourist camp and Hadza bush camps. Sometimes the drinking starts early in the day, the children don’t get fed, and drunk men beat women, Abels says. The Hadza themselves recognize that trend, and complain about being “tired” in camp, Yatsuka says. Turnover is high, as Hadza go into the bush to recover. Yatsuka is now studying how competition to sell souvenirs affects the Hadza’s egalitarian culture.
Meeting Resistance, Caroline Ash. science 360 (2018), 726–727.
Today, we find ourselves at the nexus of an alarming acceleration of resistance to antibiotics, insecticides, and herbicides. We urgently need to revisit our reliance on chemicals to ensure our future medical and food security.
Shuai Li, Pitch imperfect. science 360 (2018), 678.
Holding the $ 10,000 check felt unreal. It represented almost half of my annual stipend as a graduate student, and I had earned it in just 3 days by pitching my startup idea at the first Idaho Entrepreneur Challenge. Standing at center stage on the top floor of the tallest building in the state capital, facing an audience of prominent businesspeople, politicians, and other young entrepreneurs, I felt like a celebrity. My success was all the more rewarding because, as a nonnative English speaker, I had spent the previous 8 years struggling with a lack of confidence in my ability to communicate.
Barbara A. Wanchisen, There’s no shame in leaving. science 360 (2018), 826.
Surrounded by half-unpacked boxes in my new home, alone in a new city, and just starting to get a feel for a new job, I was plagued by suspicions that I had made the wrong choice. Maybe the naysayers were right. Maybe I was crazy to leave my tenured post in the Midwest, not to mention my friends and colleagues, for a job as the executive director of a small nonprofit organization in Washington, D.C. But I had spent a lifetime in academia, and I was excited to explore this new world.
George Athas, The Tel Dan Inscription, A Reappraisal and a New Interpretation. Journal for the Study of the Old Testament Supplement 360 (London 2003). Dissertation, University of Sydney.
Second, scholars should be warned about preconceptions when it comes to the biblical texts. The historicity of the United Monarchy has been steadily eroded by the lack of supporting evidence from excavations. Yet we must question what it actually is we are looking for in excavations to inform us about the biblical texts concerning David, Solomon and Jerusalem, if indeed it is even a question that should be asked. The extensive conclusions of Jamieson-Drake1 against a Davidic empire signalled the death knell for the United Monarchy. However, it by no means banished the persons of David or Solomon into the ether of mythical characters. Rather, it appears that for too long we have been understanding the term ‘United Monarchy’ from a modern European perspective that inherently requires state entities to possess land and officialdom. However, upon closer inspection of the biblical texts, it becomes clear that the texts themselves do not press for such an understanding. We have, therefore, been misunderstanding the biblical texts or have trained our sights too high. It may well be argued that when it comes to the ‘United Monarchy’ terms such as ‘monarchy’, ‘state’ or ‘empire’ are false or anachronistic at best. It may be the case that a period of ‘United Monarchy’ should be rebadged as the ‘United Quasi-State’ or ‘United Para-State’ or even ‘United Racket’. The answers to such questions must await further research. However, when interpreting archaeological remains and then comparing them with biblical texts, archaeologists and historians alike must be careful not to be comparing the archaeological record with false expectations or misunderstandings. In other words, it is a close and accurate reading of the biblical texts that must work alongside (not in replacement of) the interpretation of artefactual evidence. When it comes to the books of Samuel-Kings, we must look again at what the literature itself is saying.
Diego R. Barneche, D. Ross Robertson, Craig R. White & Dustin J. Marshall, Fish reproductive-energy output increases disproportionately with body size. science 360 (2018), 642–645.
Body size determines total reproductive-energy output. Most theories assume reproductive output is a fixed proportion of size, with respect to mass, but formal macroecological tests are lacking. Management based on that assumption risks underestimating the contribution of larger mothers to replenishment, hindering sustainable harvesting. We test this assumption in marine fishes with a phylogenetically controlled meta-analysis of the intraspecific mass scaling of reproductive-energy output. We show that larger mothers reproduce disproportionately more than smaller mothers in not only fecundity but also total reproductive energy. Our results reset much of the theory on how reproduction scales with size and suggest that larger mothers contribute disproportionately to population replenishment. Global change and overharvesting cause fish sizes to decline; our results provide quantitative estimates of how these declines affect fisheries and ecosystem-level productivity.
Jae Hoon Jeong, Dong Kun Lee, Shun-Mei Liu, Streamson C. Chu, Jr., Gary J. Schwartz & Young-Hwan Jo, Activation of temperature-sensitive TRPV1-like receptors in ARC POMC neurons reduces food intake. PLoS Biology 16 (2018), e2004399. <DOI:10.1371/journal.pbio.2004399>.
Proopiomelanocortin (POMC) neurons in the arcuate nucleus of the hypothalamus (ARC) respond to numerous hormonal and neural signals, resulting in changes in food intake. Here, we demonstrate that ARC POMC neurons express capsaicin-sensitive transient receptor potential vanilloid 1 receptor (TRPV1)-like receptors. To show expression of TRPV1-like receptors in ARC POMC neurons, we use single-cell reverse transcription-polymerase chain reaction (RT-PCR), immunohistochemistry, electrophysiology, TRPV1 knockout (KO), and TRPV1-Cre knock-in mice. A small elevation of temperature in the physiological range is enough to depolarize ARC POMC neurons. This depolarization is blocked by the TRPV1 receptor antagonist and by Trpv1 gene knockdown. Capsaicin-induced activation reduces food intake that is abolished by a melanocortin receptor antagonist. To selectively stimulate TRPV1-like receptor-expressing ARC POMC neurons in the ARC, we generate an adeno-associated virus serotype 5 (AAV5) carrying a Cre-dependent channelrhodopsin2 (ChR2)±enhanced yellow fluorescent protein (eYFP) expression cassette under the control of the two neuronal POMC enhancers (nPEs). Optogenetic stimulation of TRPV1-like receptor-expressing POMC neurons decreases food intake. Hypothalamic temperature is rapidly elevated and reaches to approximately 39 C during treadmill running. This elevation is associated with a reduction in food intake. Knockdown of the Trpv1 gene exclusively in ARC POMC neurons blocks the feeding inhibition produced by increased hypothalamic temperature. Taken together, our findings identify a melanocortinergic circuit that links acute elevations in hypothalamic temperature with acute reductions in food intake.
Summary: Intense exercise acutely decreases appetite and subsequent food intake. As exercise is accompanied by increased body temperature, we hypothesized that a rise in body temperature during exercise plays a role in reducing food intake. The hypothalamic neurons are major components of the neural circuits that control feeding in response to hormones and neural signals. Among hypothalamic neurons, those that express proopiomelanocortin (POMC) in the arcuate nucleus of the hypothalamus are important in controlling food intake. In this study, we found that these POMC-expressing neurons express TRPV1-like thermoreceptors that are activated by an increase in temperature within the physiological range in mice. We also showed that an increase in body temperature during exercise is directly sensed by these POMC-expressing neurons through activation of the TRPV1-like receptors. Hence, this study provides a novel perspective on the cellular mechanisms underlying energy balance: body temperature reduces food intake via TRPV1-like receptors in POMC-expressing neurons in the arcuate nucleus of the hypothalamus.
Chris R. Sims, Efficient coding explains the universal law of generalization in human perception. science 360 (2018), 652–656.
Perceptual generalization and discrimination are fundamental cognitive abilities. For example, if a bird eats a poisonous butterfly, it will learn to avoid preying on that species again by generalizing its past experience to new perceptual stimuli. In cognitive science, the “universal law of generalization” seeks to explain this ability and states that generalization between stimuli will follow an exponential function of their distance in “psychological space.” Here, I challenge existing theoretical explanations for the universal law and offer an alternative account based on the principle of efficient coding. I show that the universal law emerges inevitably from any information processing system (whether biological or artificial) that minimizes the cost of perceptual error subject to constraints on the ability to process or transmit information.
Sturt W. Manning, Carol Griggs, Brita Lorentzen, Christopher Bronk Ramsey, David Chivall, A. J. Timothy Jull & Todd E. La, Fluctuating radiocarbon offsets observed in the southern Levant and implications for archaeological chronology debates. PNAS 115 (2018), 6141–6146.
Considerable work has gone into developing high-precision radiocarbon (14C) chronologies for the southern Levant region during the Late Bronze to Iron Age/early Biblical periods ( 1200–600 BC), but there has been little consideration whether the current standard Northern Hemisphere 14C calibration curve (IntCal13) is appropriate for this region. We measured 14C ages of calendar-dated tree rings from AD 1610 to 1940 from southern Jordan to investigate contemporary 14C levels and to compare these with IntCal13. Our data reveal an average offset of 19 14C years, but, more interestingly, this offset seems to vary in importance through time. While relatively small, such an offset has substantial relevance to high-resolution 14C chronologies for the southern Levant, both archaeological and paleoenvironmental. For example, reconsidering two published studies, we find differences, on average, of 60 % between the 95.4 % probability ranges determined from IntCal13 versus those approximately allowing for the observed offset pattern. Such differences affect, and even potentially undermine, several current archaeological and historical positions and controversies.
Keywords: radiocarbon | calibration | radiocarbon offsets | southern Levant | archaeology
Significance: We observe a substantive and fluctuating offset in measured radiocarbon ages between plant material growing in the southern Levant versus the standard Northern Hemisphere radiocarbon calibration dataset derived from trees growing in central and northern Europe and North America. This likely relates to differences in growing seasons with a climate imprint. This finding is significant for, and affects, any radiocarbon application in the southern Levant region and especially for high-resolution archaeological dating—the focus of much recent work and scholarly debate, especially surrounding the timeframe of the earlier Iron Age (earlier Biblical period). Our findings change the basis of this debate; our data point to lower (more recent) ages by variously a few years to several decades.
Joel W. Ager & Alexei A. Lapkin, Chemical storage of renewable energy. science 360 (2018), 707–708.
A stable electrochemical cell selectively produces ethylene from carbon dioxide.
They measured a full-cell energy conversion efficiency, which captures all losses (overpotentials at the cathode and anode and electrical resistance of the electrolyte), of 34 %. This value is lower than the 60 to 80 % achieved for water splitting but is comparable to CO2-reduction cells, which make one-carbon products such as CO or formate and have lower cathode overpotentials. Although the work of Dinh et al. is an important step toward chemical storage of renewable energy, challenges remain. Their reactor, and indeed nearly all CO2-reduction reactors in the literature, makes products which are either entrained in the CO2 stream or dissolved in the electrolyte, leaving product separation as an unsolved challenge.
Cao-Thang Dinh et al., CO2 electroreduction to ethylene via hydroxide-mediated copper catalysis at an abrupt interface. science 360 (2018), 783–787.
Cao-Thang Dinh, Thomas Burdyny, Md Golam Kibria, Ali Seifitokaldani, Christine M. Gabardo, F. Pelayo García de Arquer, Amirreza Kiani, Jonathan P. Edwards, Phil De Luna, Oleksandr S. Bushuyev, Chengqin Zou, Rafael Quintero-Bermudez, Yuanjie Pang, David Sinton & Edward H. Sargent
Carbon dioxide (CO2) electroreduction could provide a useful source of ethylene, but low conversion efficiency, low production rates, and low catalyst stability limit current systems. Here we report that a copper electrocatalyst at an abrupt reaction interface in an alkaline electrolyte reduces CO2 to ethylene with 70 % faradaic efficiency at a potential of -0.55 volts versus a reversible hydrogen electrode (RHE). Hydroxide ions on or near the copper surface lower the CO2 reduction and carbon monoxide (CO)–CO coupling activation energy barriers; as a result, onset of ethylene evolution at -0.165 volts versus an RHE in 10 molar potassium hydroxide occurs almost simultaneously with CO production. Operational stability was enhanced via the introduction of a polymer-based gas diffusion layer that sandwiches the reaction interface between separate hydrophobic and conductive supports, providing constant ethylene selectivity for an initial 150 operating hours.
Christian Robin, Le Yémen entre judaïsme et christianisme. (Online 1998). <http://www.clio.fr/BIBLIOTHEQUE/le_yemen_entre_judaisme_et_christianisme.asp> (2018-06-13).
Elizabeth S. Jeffers et al., Plant controls on Late Quaternary whole ecosystem structure and function. Ecology Letters 21 (2018), 814–825.
Elizabeth S. Jeffers, Nicki J. Whitehouse, Adrian Lister, Gill Plunkett, Phil Barratt, Emma Smyth, Philip Lamb, Michael W. Dee, Stephen J. Brooks, Katherine J. Willis, Cynthia A. Froyd Jenny E. Watson & Michael B. Bonsall
Plants and animals influence biomass production and nutrient cycling in terrestrial ecosystems; however, their relative importance remains unclear. We assessed the extent to which megaherbivore species controlled plant community composition and nutrient cycling, relative to other factors during and after the Late Quaternary extinction event in Britain and Ireland, when twothirds of the region’s mega-herbivore species went extinct. Warmer temperatures, plant–soil and plant–plant interactions, and reduced burning contributed to the expansion of woody plants and declining nitrogen availability in our five study ecosystems. Shrub biomass was consistently one of the strongest predictors of ecosystem change, equalling or exceeding the effects of other biotic and abiotic factors. In contrast, there was relatively little evidence for mega-herbivore control on plant community composition and nitrogen availability. The ability of plants to determine the fate of terrestrial ecosystems during periods of global environmental change may therefore be greater than previously thought.
Keywords: Climate change | landscape burning | megafauna extinction | nutrient cycling | plant community composition | plant–plant interactions | plant–soil interactions.
Summary: In conclusion, our results do not support the prevailing notion that the loss of mega-herbivore species caused the expansion of woody plants (Zimov et al. 2012; Bakker et al. 2016) and declining ecosystem fertility (Doughty et al. 2016) in terrestrial ecosystems at the end of the last glacial period. Instead, our findings indicate a relatively high level of plant control on ecosystem structure and function, an effect which has heretofore been largely overlooked as a direct driver of Late Quaternary ecosystem change (Willis et al. 1997; Jeffers et al. 2011b, 2015b). We suggest that interactions among plant growth forms and plant–soil feedbacks may have been more important than trophic interactions in determining changes in terrestrial nitrogen availability and above-ground plant biomass in northern European ecosystems as the Earth transitioned out of the last glacial period. Overall, our results indicate that the mega-herbivores remaining in these ecosystems were not able to stem the expansion of woody plants at the onset of post-glacial warming. Instead, it appears likely that plants strongly influenced the fate of the once extensive steppe-tundra biome in northwestern Europe.
Jeremy D. Shakun et al., Minimal East Antarctic Ice Sheet retreat onto land during the past eight million years. nature 558 (2018), 284–287.
Jeremy D. Shakun, Lee B. Corbett, Paul R. Bierman, Kristen Underwood, Donna M. Rizzo, Susan R. Zimmerman, Marc W. Caffee, Tim Naish, Nicholas R. Golledge & Carling C. Hay
The East Antarctic Ice Sheet (EAIS) is the largest potential contributor to sea-level rise. However, efforts to predict the future evolution of the EAIS are hindered by uncertainty in how it responded to past warm periods, for example, during the Pliocene epoch (5.3 to 2.6 million years ago), when atmospheric carbon dioxide concentrations were last higher than 400 parts per million. Geological evidence indicates that some marine-based portions of the EAIS and the West Antarctic Ice Sheet retreated during parts of the Pliocene1,2, but it remains unclear whether ice grounded above sea level also experienced retreat. This uncertainty persists because global sea-level estimates for the Pliocene have large uncertainties and cannot be used to rule out substantial terrestrial ice loss3, and also because direct geological evidence bearing on past ice retreat on land is lacking. Here we show that land-based sectors of the EAIS that drain into the Ross Sea have been stable throughout the past eight million years. We base this conclusion on the extremely low concentrations of cosmogenic 10Be and 26Al isotopes found in quartz sand extracted from a land-proximal marine sediment core. This sediment had been eroded from the continent, and its low levels of cosmogenic nuclides indicate that it experienced only minimal exposure to cosmic radiation, suggesting that the sediment source regions were covered in ice. These findings indicate that atmospheric warming during the past eight million years was insufficient to cause widespread or long-lasting meltback of the EAIS margin onto land. We suggest that variations in Antarctic ice volume in response to the range of global temperatures experienced over this period—up to 2–3 degrees Celsius above preindustrial temperatures4, corresponding to future scenarios involving carbon dioxide concentrations of between 400 and 500 parts per million—were instead driven mostly by the retreat of marine ice margins, in agreement with the latest models5,6.
Klaus-G. Hinzen et al., Reassessing the Mycenaean Earthquake Hypothesis, Results of the HERACLES Project from Tiryns and Midea, Greece. Bulletin of the Seismological Society of America 108 (2018), 1046–1070.
Klaus-G. Hinzen, Joseph Maran, Hector Hinojosa-Prieto,* Ursula Damm-Meinhardt, Sharon K. Reamer, Jana Tzislakis, Kilian Kemna, Gregor Schweppe, Claus Fleischer, and Katie Demakopoulou
Observations at Mycenaean archaeological sites of tilted and curved walls, broken pottery, and human skeletons led to the hypothesis that these sites in the Argolid, Peloponnese, Greece, were destroyed in large earthquakes between the late palatial (thirteenth century B.C.E.) and postpalatial (1200–1050 B.C.E.) periods. In particular, the destruction of Mycenaean palaces around 1200/1190 B.C.E. has often been attributed to a devastating earthquake. To test the Mycenaean earthquake hypothesis, this project focuses on the Argive citadels of Tiryns and Midea. With active and passive seismic measurements complemented by a gravimetric survey, we explored seismic site effects at these locations and calculated synthetic seismograms for potential earthquake sources to estimate intensities of ground motions inside and outside the citadels. The field work and results were supplemented by analysis of the individual damage descriptions and observations from the archaeological literature on which the hypothesis is based. Because of poor construction techniques and the associated site effects, the buildings in the Lower Town surrounding the citadel of Tiryns were more vulnerable than the structures within the Cyclopean palace walls, but evidence of an earthquake destruction stratum in the Lower Town has not yet been found. Although some of the observations from the two investigated citadels could be explained by seismic loading, alternative nonseismic causes could equally explain most observed damage. In some cases, the structural damage was clearly not caused by earthquakes. Simulated ground motions show that severe earthquake damage at Tiryns and Midea can be expected from activation of local faults in the Argive basin; however, palaeoseismic studies for such activity in and since the Late Bronze Age (LBA) are lacking. Our results indicate that the hypothesis of a destructive earthquake in Tiryns and Midea, which may have contributed to the end of the LBA Mycenaean palatial period, is unlikely.
Michael Price, Finding the first horse tamers. science 360 (2018), 587.
Genes suggest that Central Asian hunter-gatherers, not famed Yamnaya herders, first domesticated horses.
The team found no Yamnaya DNA in the three Botai individuals, suggesting the two groups hadn’t mixed. That implies the Botai domesticated horses on their own, says Willerslev, first hunting the animals, then managing herds for food, and finally using them for other purposes. “It’s an extremely important achievement from a group of people we all think of as being pretty simple,” he says. The Yamnaya used horses to migrate far and wide. Yet Willerslev’s team found little Yamnaya DNA in Central and South Asia. They saw no trace of it in ancient people from Anatolia in modern Turkey, where Hittite, an early branch of PIE, was likely spoken. That suggests Hittite likely didn’t evolve from a language brought by the Yamnaya. “What we see does not support a classical way of looking at the steppe hypothesis,” Willerslev says.
Peter Brown, Ransom Of The Soul, Afterlife and wealth in early western christianity. (Cambridge 2018).
Marking a departure in our understanding of Christian views of the afterlife from 250 to 650 CE, The Ransom of the Soul explores a revolutionary shift in thinking about the fate of the soul that occurred around the time of Rome’s fall. Peter Brown describes how this shift transformed the Church’s institutional relationship to money and set the stage for its domination of medieval society in the West.
[An] extraordinary new book—Prodigiously original—an astonishing performance for a historian who has already been so prolific and influential—Peter Brown’s subtle and incisive tracking of the role of money in Christian attitudes toward the afterlife not only breaks down traditional geographical and chronological boundaries across more than four centuries. It provides wholly new perspectives on Christianity itself, its evolution, and, above all, its discontinuities. It demonstrates why the Middle Ages, when they finally arrived, were so very different from late antiquity.
G. W. Bowersock, New York Review of Books
Fred M. Donner, Hagarism: The Making of the Islamic World. Middle East Studies Association Bulletin 40 (2006), 197–199.
Hagarism: The Making of the Islamic World, by Patricia Crone and Michael Cook. Cambridge: Cambridge University Press, 1977.
Crone and Cook’s basic argument was a methodological one and, essentially, They started by reminding us of something everyone already knew: that the generally accepted picture of Islam’s origins was based not on contemporary documents, but on various narrative sources that had been compiled by Muslims years, sometimes years, after the events they described. The usual justification for accepting these later as evidence was that they were accurate accounts of “what had actually happened” time of Islam’s genesis, but Crone and Cook pointed out that a long tradition of Western scholarship, going back at least to the mid-nineteenth century, had increasingly cast on this assumption (the works of Goldziher, Schacht, Noth, and many others were in particular). The authors therefore proposed that, since the narrative materials problematic, scholars should leave them aside and, at least as a heuristic exercise, see what could be said about Islam’s origins by relying solely on contemporary, contemporary, evidence.
Not everything that Crone and Cook proposed in Hagarism was, of course, right. Or even fair: for example, the authors sometimes seem willing to accept non-Muslim literary sources without the kind of unsparing criticism they used to justify their rejection of the whole corpus of Arabic-Islamic sources. Neither was Hagarism an easy read: its arguments were sometimes labyrinthine, and the authors’ ideas were often incomprehensible to those who lacked strong specialist training (and even to many who had it). But, despite its shortcomings, the basic methodological point of Hagarism—that historians of Islamic origins need to behave truly as historians, and subject their sources to rigorous criticism—was positive, valuable, and long overdue in a field that was so hidebound that it often resisted looking at the real evidence.
Ilkka Lindstedt, The Religious and Spiritual Life of the Jews of Medina. Studia Orientalia Electronica 4 (2016), 150–154. <http://journal.fi/store/article/view/58354>.
Haggai Mazuz. The Religious and Spiritual Life of the Jews of Medina. (The Brill Reference Library of Judaism 38) Leiden: Brill, 2014. ISBN 978-90-04-25062-8. xvi + 132 pp.
Unfortunately, to me the study reads like an apologetic attempt to prove the “orthodoxy” of Medinese Jews. It furthermore fails because the principal evidence used in the study, Islamic-era Arabic literature, is, in the main, unreliable and unusable for studying the question of the religious nature and identity of the Jewish inhabitants in Medina. The book’s premises, then, are problematic. Furthermore, awareness of the newest research on pre- and early Islamic Arabia is not displayed in it. Because of my own background, I will comment on the book largely from the point of view of Islamic studies, even though there would probably be much to take issue with from the perspective of Jewish studies too. One would, for example, have hoped a discussion on the position of the Talmud in the sixth–seventh century Near East more generally.
This book can be recommended for researchers wishing to learn how Medinese Jews were portrayed in Muslim religious and historical literature. The Arabic texts are indeed handled skillfully, as far as they go. There are also thought-provoking comparisons between Muslim and Jewish texts. Unfortunately, the study, although short, is not really worthwhile reading for a student or scholar interested in actual historical details of Medinese or Arabian Jews or their late antique context.
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