311 research outputs found
Is there a 'Neutral theory of Anthropology'?
Lansing and Cox open a welcome discussion of the potential for neutral models in anthropologyâit has been almost 50 years since the original neutral models were applied to DNA sequences (e.g., Kimura 1968) and then later to biological phenotypes (e.g., Lande 1976) and cultural data (Cavalli-Sforza and Feldman 1981; Neiman 1995). This long history of research is a gold mine for studies of culture evolution
Predictability in an unpredictable artificial cultural market
In social, economic and cultural situations in which the decisions of
individuals are influenced directly by the decisions of others, there appears
to be an inherently high level of ex ante unpredictability. In cultural markets
such as films, songs and books, well-informed experts routinely make
predictions which turn out to be incorrect.
We examine the extent to which the existence of social influence may,
somewhat paradoxically, increase the extent to which winners can be identified
at a very early stage in the process. Once the process of choice has begun,
only a very small number of decisions may be necessary to give a reasonable
prospect of being able to identify the eventual winner.
We illustrate this by an analysis of the music download experiments of
Salganik et.al. (2006). We derive a rule for early identification of the
eventual winner. Although not perfect, it gives considerable practical success.
We validate the rule by applying it to similar data not used in the process of
constructing the rule
Evaluating reproductive decisions as discrete choices under social influence
Discrete choice, coupled with social influence, plays a significant role in evolutionary studies of human fertility, as investigators explore how and why reproductive decisions are made. We have previously proposed that the relative magnitude of social influence can be compared against the transparency of pay-off, also known as the transparency of a decision, through a heuristic diagram that maps decision-making along two axes. The horizontal axis represents the degree to which an agent makes a decision individually versus one that is socially influenced, and the vertical axis represents the degree to which there is transparency in the pay-offs and risks associated with the decision the agent makes. Having previously parametrized the functions that underlie the diagram, we detail here how our estimation methods can be applied to real-world datasets concerning sexual health and contraception
Genetic stability of pneumococcal isolates during 35 days of human experimental carriage
Background
Pneumococcal carriage is a reservoir for transmission and a precursor to pneumococcal disease. The experimental human pneumococcal carriage model provides a useful tool to aid vaccine licensure through the measurement of vaccine efficacy against carriage (VEcol). Documentation of the genetic stability of the experimental human pneumococcal carriage model is important to further strengthen confidence in its safety and conclusions, enabling it to further facilitate vaccine licensure through providing evidence of VEcol.
Methods
229 isolates were sequenced from 10 volunteers in whom experimental human pneumococcal carriage was established, sampled over a period of 35 days. Multiple isolates from within a single volunteer at a single time provided a deep resolution for detecting variation. HiSeq data from the isolates were mapped against a PacBio reference of the inoculum to call variable sites.
Results
The observed variation between experimental carriage isolates was minimal with the maximum SNP distance between any isolate and the reference being 3 SNPs.
Conclusion
The low-level variation described provides evidence for the stability of the experimental human pneumococcal carriage model over 35 days, which can be reliably and confidently used to measure VEcol and aid future progression of pneumococcal vaccination
Shifting gender relations at Khok Phanom Di, Thailand: Isotopic evidence from the skeletons
The values for isotopes of strontium, carbon, and oxygen in human tooth enamel from the prehistoric site of Khok Phanom Di (ca. 2100â1500 BC) in Thailand shed light on human mobility and marital residence during a crucial period of subsistence change. Khok Phanom Di was a sedentary coastal community that apparently relied on hunting, gathering, and fishing in the midst of a transition to rice agriculture in the interior. The results of the isotope analyses indicate female immigration and then a marked shift to local strontium isotope signatures among females accompanied by a clear increase in the prestige of female burials. A possible explanation is a shift in the pattern of exogamy with a concomitant change in gender relations. Observation of a very similar transition at Ban Chiang, in northeastern Thailand, suggests the possibility of a regionwide social transition. In the case of Khok Phanom Di, the increasing role of females in producing high-quality ceramic vessels may have contributed to the change
Das bandkeramische GrĂ€berfeld vom âViesenhĂ€user Hofâ bei Stuttgart-MĂŒhlhausen: Neue Untersuchungsergebnisse zum Migrationsverhalten im frĂŒhen Neolithikum
Einleitung: Gegenstand des vorliegenden Beitrags ist die Rolle der MobilitĂ€t im Leben der frĂŒhen Ackerbauern
und ViehzĂŒchter in SĂŒdwestdeutschland. Seit Jahrzehnten werden wissenschaftliche Auseinandersetzungen
ĂŒber die Bedeutung von Wanderungsbewegungen bei der Ausbreitung der produzierenden Wirtschaftsweise in Europa zwischen 7000 und 4000 v. Chr. gefĂŒhrt. Dabei gehen traditionelle Ăberlegungen davon aus, dass die ersten Ackerbauern in Mitteleuropa Zuwanderer waren, die ein
âPaketâ neuer Errungenschaften und Ideen mit sich fĂŒhrten, das u. a. Haustiere, dauerhafte Siedlungen, Keramik und den Ackerbau enthielt.1 Neuere Untersuchungen und Ăberlegungen gestehen dagegen der einheimischen Bevölkerung eine maĂgebliche Bedeutung bei der Ăbernahme der neolithischen
Wirtschaftsweise zu.2 Die MobilitĂ€t des Menschen ist aber nicht nur fĂŒr die ErklĂ€rung des Neolithisierungsprozesses, sondern auch fĂŒr das VerstĂ€ndnis der Lebens- und Wirtschaftsweise der Menschen in den mittleren und spĂ€teren Abschnitten der Linearbandkeramik von höchstem
Interesse.
Die bisherige Forschungsdiskussion basierte in diesem Zusammenhang ĂŒberwiegend auf indirekten Argumenten, d. h. auf Artefakten, die auch getauscht oder gestohlen worden sein konnten, aber nicht auf den Ăberresten der potenziellen Zuwanderer selbst, die in Form von Knochen und ZĂ€hnen erhalten sind.
Die vorliegende Studie bedient sich der direkten Analyse menschlicher Skelettreste der bandkeramischen GrĂ€ber vom âViesenhĂ€user Hofâ, Stuttgart-MĂŒhlhausen, mittels anthropologischer Untersuchungen und Strontiumisotopenanalysen. Nachfolgend werden der Fundplatz in seinem archĂ€ologischen Kontext der Linearbandkeramik sowie die Ergebnisse der anthropologischen Untersuchungen
und Strontiumisotopenanalysen vorgestellt und dann die Rolle der MobilitĂ€t im Leben der frĂŒhen Ackerbauern und ViehzĂŒchter sowie fĂŒr die Ausbreitung der neolithischen Wirtschaftsweise diskutiert.
Stuttgart-MĂŒhlhausen ist eines der Ă€ltesten bandkeramischen GrĂ€berfelder, die bislang fĂŒr derartige Untersuchungen zur VerfĂŒgung standen
Updated guidelines for gene nomenclature in wheat
The last decade has seen a proliferation in genomic resources for wheat, including reference- and pan-genome assemblies with gene annotations, which provide new opportunities to detect, characterise, and describe genes that influence traits of interest. The expansion of genetic information has supported growth of the wheat research community and catalysed strong interest in the genes that control agronomically important traits, such as yield, pathogen resistance, grain quality, and abiotic stress tolerance. To accommodate these developments, we present an updated set of guidelines for gene nomenclature in wheat. These guidelines can be used to describe loci identified based on morphological or phenotypic features or to name genes based on sequence information, such as similarity to genes characterised in other species or the biochemical properties of the encoded protein. The updated guidelines provide a flexible system that is not overly prescriptive but provides structure and a common framework for naming genes in wheat, which may be extended to related cereal species. We propose these guidelines be used henceforth by the wheat research community to facilitate integration of data from independent studies and allow broader and more efficient use of text and data mining approaches, which will ultimately help further accelerate wheat research and breeding.EEA PergaminoFil: Boden, S. A. University of Adelaide. Waite Research Institute. School of Agriculture, Food and Wine; AustraliaFil: McIntosh, R .A. University of Sydney. School of Life and Environmental Sciences. Plant Breeding Institute; AustraliaFil: Uauy, C. Norwich Research Park. John Innes Centre; Reino UnidoFil: Krattinger, S. G. King Abdullah University of Science and Technology. Biological and Environmental Science and Engineering Division. Plant Science Program; Arabia SauditaFil: Krattinger, S. G. The Wheat Initiative; AlemaniaFil: Dubcovsky, J. University of California. Department of Plant Science; Estados UnidosFil: Dubcovsky, J. The Wheat Initiative; AlemaniaFil: Rogers, W.J. Universidad Nacional del Centro de La Provincia de Buenos Aires. Facultad de AgronomĂa (CIISAS, CIC-BIOLAB AZUL, CONICET-INBIOTEC, CRESCA). Departamento de BiologĂa Aplicada; ArgentinaFil: Rogers, W.J. The Wheat Initiative; AlemaniaFIL: Xia, X. C. Chinese Academy of Agricultural Sciences. National Wheat Improvement Centre. Institute of Crop Science; ChinaFil: Badaeva, E. D. Russian Academy of Sciences. N.I. Vavilov Institute of General Genetics; RusiaFil: Bentley, A. R. International Maize and Wheat Improvement Center (CIMMYT); MĂ©xicoFil: Bentley, A. R. The Wheat Initiative; AlemaniaFil: Brown-Guedira, G. North Carolina State University. USDA-ARS Plant Science Research; Estados UnidosFil: Brown-Guedira, G. The Wheat Initiative; AlemaniaFil: GonzĂĄlez, Fernanda G. Instituto Nacional de TecnologĂa Agropecuaria (INTA). EstaciĂłn Experimental Agropecuaria Pergamino. SecciĂłn EcofisiologĂa; ArgentinaFil: GonzĂĄlez, Fernanda G. Centro de Investigaciones y Transferencia del Noroeste de la Provincia de Buenos Aires (CITNOBA, CONICET-UNNOBA-UNSADA); ArgentinaFil: GonzĂĄlez, Fernanda G. The Wheat Initiative; AlemaniaFil: Zhang, Y. Fudan University. School of Life Sciences. Institute of Plant Biology. Collaborative Innovation Center of Genetics and Development. State Key Laboratory of Genetic Engineering; Chin
Snow petrel stomach-oil deposits as a new biological archive of Antarctic sea ice
Where snow petrels forage is predominantly a function of sea ice. They spit stomach oil in defence, and accumulated deposits at nesting sites are providing new opportunities to reconstruct their diet, and, in turn, the sea-ice environment over past millennia
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