Discover the most talked about and latest scientific content & concepts.

Concept: History


Ancient DNA research is revealing a human history far more complex than that inferred from parsimonious models based on modern DNA. Here, we review some of the key events in the peopling of the world in the light of the findings of work on ancient DNA.

Concepts: DNA, Species, Science, World, History, Prehistory, Ancient history, Occam's razor


The concept of “scientific culture” varies historically, and the examination of its continuities and transformations can help us understand the relationship between the scientific community and society. The views on the role of science in society go far beyond the advancement of a particular form of knowledge and its possible or promising fruit. They involve values, postures and practices to be disseminated and reveal expectations of social and cultural advancement. This article discusses four expressive visions of different moments in Brazilian history. The formulations of four influential authors in scientific and educational policies of the country at different times are presented and analyzed: Miguel Ozorio de Almeida, Anísio Teixeira, Maurício Rocha e Silva and Carlos Vogt.

Concepts: Scientific method, Sociology, Science, Culture, Anthropology, History, 1980 births, Association football defenders


The importance of the Grimaldi complex of caves and rock shelters is twofold: scientific and historical. Scientifically, it is one of the major Upper Paleolithic sites, considering the variety of mobiliary and parietal art, the number of single and multiple burials and associated grave goods, and the abundant lithic and fauna remains. Historically, the documentation of activity that took place in this site starting from the second half of the 19 th century and the studies carried out on the materials that have been recovered in the decades between 1870s-1910s, provide instructive examples of methods and goals of Paleolithic archeology and anthropology of the epoch. This paper combines the scientific and the historic interest of the site through a chronicle of the events that took place during the period of the most sensational discoveries, i.e. beginning with the identification in 1872 of the first Upper Paleolithic burial and ending with the results of the excavations carried out in 1901 at Grotte des Enfants published in four volumes a few years later. The paper discusses early interpretations and modern views on the different findings and documents changes in perspectives and goals of paleoanthropological research in over a century, raising some of the major issues of contemporary Upper Paleolithic studies.

Concepts: Science, Anthropology, Social sciences, History, Paleolithic, Stone Age, Burial, Upper Paleolithic


How did human societies evolve from small groups, integrated by face-to-face cooperation, to huge anonymous societies of today, typically organized as states? Why is there so much variation in the ability of different human populations to construct viable states? Existing theories are usually formulated as verbal models and, as a result, do not yield sharply defined, quantitative predictions that could be unambiguously tested with data. Here we develop a cultural evolutionary model that predicts where and when the largest-scale complex societies arose in human history. The central premise of the model, which we test, is that costly institutions that enabled large human groups to function without splitting up evolved as a result of intense competition between societies-primarily warfare. Warfare intensity, in turn, depended on the spread of historically attested military technologies (e.g., chariots and cavalry) and on geographic factors (e.g., rugged landscape). The model was simulated within a realistic landscape of the Afroeurasian landmass and its predictions were tested against a large dataset documenting the spatiotemporal distribution of historical large-scale societies in Afroeurasia between 1,500 BCE and 1,500 CE. The model-predicted pattern of spread of large-scale societies was very similar to the observed one. Overall, the model explained 65% of variance in the data. An alternative model, omitting the effect of diffusing military technologies, explained only 16% of variance. Our results support theories that emphasize the role of institutions in state-building and suggest a possible explanation why a long history of statehood is positively correlated with political stability, institutional quality, and income per capita.

Concepts: Scientific method, Evolution, Sociology, Science, History, Society, Institution, Civilization


Periodization theory has, over the past seven decades, emerged as the preeminent training planning paradigm. The philosophical underpinnings of periodization theory can be traced back to the integration of diverse shaping influences, whereby coaching beliefs and traditions were blended with historically available scientific insights and contextualized against pervading social planning models. Since then, many dimensions of elite preparation have evolved significantly, as driven by a combination of coaching innovations and science-led advances in training theory, techniques, and technologies. These advances have been incorporated into the fabric of the pre-existing periodization planning framework, yet the philosophical assumptions underpinning periodization remain largely unchallenged and unchanged. One particularly influential academic sphere of study, the science of stress, particularly the work of Hans Selye, is repeatedly cited by theorists as a central pillar upon which periodization theory is founded. A fundamental assumption emanating from the early stress research is that physical stress is primarily a biologically mediated phenomenon: a presumption translated to athletic performance contexts as evidence that mechanical training stress directly regulates the magnitude of subsequent ‘fitness’ adaptations. Interestingly, however, since periodization theory first emerged, the science of stress has evolved extensively from its historical roots. This raises a fundamental question: if the original scientific platform upon which periodization theory was founded has disintegrated, should we critically re-evaluate conventional perspectives through an updated conceptual lens? Realigning periodization philosophy with contemporary stress theory thus presents us with an opportunity to recalibrate training planning models with both contemporary scientific insight and progressive coaching practice.

Concepts: Scientific method, Natural selection, Truth, Epistemology, Dimension, Science, History, Eustress


The latest Intergovernmental Panel on Climate Change Assessment Report widened the equilibrium climate sensitivity (ECS) range from 2° to 4.5°C to an updated range of 1.5° to 4.5°C in order to account for the lack of consensus between estimates based on models and historical observations. The historical ECS estimates range from 1.5° to 3°C and are derived assuming a linear radiative response to warming. A Bayesian methodology applied to 24 models, however, documents curvature in the radiative response to warming from an evolving contribution of interannual to centennial modes of radiative response. Centennial modes display stronger amplifying feedbacks and ultimately contribute 28 to 68% (90% credible interval) of equilibrium warming, yet they comprise only 1 to 7% of current warming. Accounting for these unresolved centennial contributions brings historical records into agreement with model-derived ECS estimates.

Concepts: Scientific method, Mode, Ecology, Climate change, History, Intergovernmental Panel on Climate Change, Contributions, Gregorian chant


The Mongol invasion of Eastern Europe, and especially its sudden withdrawal from Hungary in 1242 CE, has generated much speculation and an array of controversial theories. None of them, however, considered multifaceted environmental drivers and the coupled analysis of historical reports and natural archives. Here we investigate annually resolved, absolutely dated and spatially explicit paleoclimatic evidence between 1230 and 1250 CE. Documentary sources and tree-ring chronologies reveal warm and dry summers from 1238-1241, followed by cold and wet conditions in early-1242. Marshy terrain across the Hungarian plain most likely reduced pastureland and decreased mobility, as well as the military effectiveness of the Mongol cavalry, while despoliation and depopulation ostensibly contributed to widespread famine. These circumstances arguably contributed to the determination of the Mongols to abandon Hungary and return to Russia. While overcoming deterministic and reductionist arguments, our ‘environmental hypothesis’ demonstrates the importance of minor climatic fluctuations on major historical events.

Concepts: Greek loanwords, History, Military, Hungary, Mongol Empire, Romania, Mongols, Genghis Khan


The potential decline of dementia, seen in light of the rise and fall of other major diseases, raises a tantalizing prospect: Can we control our burden of disease? The history of the debate on CAD decline carries important lessons for emerging reports of dementia’s decline.

Concepts: Disease, History


Do human societies from around the world exhibit similarities in the way that they are structured, and show commonalities in the ways that they have evolved? These are long-standing questions that have proven difficult to answer. To test between competing hypotheses, we constructed a massive repository of historical and archaeological information known as “Seshat: Global History Databank.” We systematically coded data on 414 societies from 30 regions around the world spanning the last 10,000 years. We were able to capture information on 51 variables reflecting nine characteristics of human societies, such as social scale, economy, features of governance, and information systems. Our analyses revealed that these different characteristics show strong relationships with each other and that a single principal component captures around three-quarters of the observed variation. Furthermore, we found that different characteristics of social complexity are highly predictable across different world regions. These results suggest that key aspects of social organization are functionally related and do indeed coevolve in predictable ways. Our findings highlight the power of the sciences and humanities working together to rigorously test hypotheses about general rules that may have shaped human history.

Concepts: Scientific method, Sociology, Science, Anthropology, Social sciences, History, Society, Humanities


Recent public debate and the scientific literature have frequently cited a “pause” or “hiatus” in global warming. Yet, multiple sources of evidence show that climate change continues unabated, raising questions about the status of the “hiatus”. To examine whether the notion of a “hiatus” is justified by the available data, we first document that there are multiple definitions of the “hiatus” in the literature, with its presumed onset spanning a decade. For each of these definitions we compare the associated temperature trend against trends of equivalent length in the entire record of modern global warming. The analysis shows that the “hiatus” trends are encompassed within the overall distribution of observed trends. We next assess the magnitude and significance of all possible trends up to 25 years duration looking backwards from each year over the past 30 years. At every year during the past 30 years, the immediately preceding warming trend was always significant when 17 years (or more) were included in the calculation, alleged “hiatus” periods notwithstanding. If current definitions of the “pause” used in the literature are applied to the historical record, then the climate system “paused” for more than 1/3 of the period during which temperatures rose 0.6 K.

Concepts: Climate, Weather, Science, Climate change, History, Solar variation, Global warming