Paleospecies as cognitive construct: The meme of “Homo floresiensis”

Creation and subsequent abandonment of a number of earlier species considered human ancestors: Eoanthropus dawsoni, Hesperopithecus haroldcooki, Homo gardarensis and Ramapithecus punjabicus is presented using cases from the history of science. This review indicates that the fossil evidence for these species has been questionable from the beginning but that mental images – memes – they invoked were attractive to students of human evolution and as such persisted even if not confirmed by further finds, with new research still being disputed. Against this background the status of the recent construction of the hominin species “Homo floresiensis” is discussed showing that despite dubious interpretations of the objective data and a relatively long time of non-confirmation due to paucity of newly discovered skeletal remains, the “species” still exists in minds of scholars and in the scientific literature extending into textbooks

MODELLING AND PROGNOSIS OF COMPETITIVE PERFORMANCES IN ELITE SWIMMING

The study demonstrates that the performance of an elite female swimmer in the finals of the 200 m backstroke at the Olympic Games 2000 in Sydney can be predicted by means of the nonlinear mathematical method of a neural back-propagation network. The analysis included the performance output data of 19 competitions prior to the Olympics within a time period of 95 successive weeks and the training input data of the last four weeks prior to each competition. The training data were divided into two phases: (1) a two-week taper cycle, and (2) an earlier two-week high load cycle. The trained neural network was not only able to model the 19 competitive performances, but also to predict the performance in the semi final of the Olympic Games in Sydney on the basis of the two sets of training data during the preparation before that specific competition

Evolution of modern humans is a result of self-amplifying feedbacks beginning in the Miocene and continuing without interruption until now

Humans are a part of the complex system of life. This consists of a multitude of feedbacks among all parts of living systems. In the case of human origins, many feedbacks became positive rather than homeostatic, thus producing self-amplifying effects in basic morphological and behavioural characteristics of emerging humans: erect bipedalism, social structure, tool-making, food procurement and environmental management, symbolic communication, sexuality, extended childhood, and mental capacities. These, plus many other human characteristics, changed gradually, though at varying rates, over the last 6 million years, producing directional variation in extant morphological and behavioural characteristics of what are considered modern humans. The change through time and geographic space of those characteristics is an ongoing dynamic process, thus it is futile to pose essentialist questions about the precise date and place of the modern human origins. Modernity is a process, not an endpoint

Imaging ancient and mummified specimens: dual-energy CT with effective atomic number imaging of two ancient Egyptian cat mummies

In mummified animals and humans, soft tissues like skin and muscle become more dense over time due to dehydration. At the same time, bone becomes less dense as marrow is replaced by air. This is a problem for the radiological examination of ancient specimens, as currently used methods such as single-energy CT and MRI rely on density and water content to produce tissue contrast in an image. Dual energy CT with effective atomic number imaging overcomes this problem, as the elemental constituents and consequently effective atomic number of a specimen remain relatively constant over time. This case study of two ancient Egyptian cat mummies demonstrates that effective atomic number imaging can differentiate desiccated soft tissues from low-density bone in ancient remains. Effective atomic number imaging has the potential for superior tissue contrast resolution when compared to single energy CT and can be used to provide new paleoradiological perspectives.James M. Bewes, Antony Morphett, F. Donald Pate, Maciej Henneberg, Andrew J. Low, Lars Kruse, Barry Craig, Aphrodite Hindson, Eleanor Adam

New perspectives on evolutionary medicine: the relevance of microevolution for human health and disease

Evolutionary medicine (EM) is a growing field focusing on the evolutionary basis of human diseases and their changes through time. To date, the majority of EM studies have used pure theories of hominin macroevolution to explain the present-day state of human health. Here, we propose a different approach by addressing more empirical and health-oriented research concerning past, current and future microevolutionary changes of human structure, functions and pathologies. Studying generation-to-generation changes of human morphology that occurred in historical times, and still occur in present-day populations under the forces of evolution, helps to explain medical conditions and warns clinicians that their current practices may influence future humans. Also, analyzing historic tissue specimens such as mummies is crucial in order to address the molecular evolution of pathogens, of the human genome, and their coadaptations.Frank Jakobus Rühli and Maciej Henneber

Energetic particle transport in optimized stellarators

Nine stellarator configurations, three quasiaxisymmetric, three quasihelically symmetric and three non-quasisymmetric are scaled to ARIES-CS size and analyzed for energetic particle content. The best performing configurations with regard to energetic particle confinement also perform the best on the neoclassical {\Gamma}c metric, which attempts to align contours of the second adiabatic invariant with flux surfaces. Quasisymmetric configurations that simultaneously perform well on {\Gamma}c and quasisymmetry have the best overall confinement, with collisional losses under 3%, approaching the performance of ITER with ferritic inserts.Comment: 18 pages, 10 figures, 1 Tabl

Assessing plant diversity and composition in grasslands across spatial scales: the standardised EDGG sampling methodology

This paper presents the details of the EDGG sampling methodology and its underlying rationales. The methodology has been applied during EDGG Research Expeditions and EDGG Field Workshops since 2009, and has been subsequently adopted by various other researchers. The core of the sampling are the EDGG Biodiversity Plots, which are 100‐m2 squares comprising, in two opposite corners, nested‐plot series of 0.0001, 0.001, 0.01, 0.1, 1 and 10 m2 square plots, in which all terricolous vascular plants, bryophytes and lichens are recorded using the shoot presence method. In the 10‐m2 plots, species cover is also estimated as a percentage and various environmental and structural parameters are recorded. Usually the EDGG Biodiversity Plots are complemented by the sampling of additional 10 m2 normal plots with the same parameters as the 10‐m2 corners of the first, allowing coverage of a greater environmental diversity and the achievement of higher statistical power in the subsequent analyses for this important grain size. The EDGG sampling methodology has been refined over the years, while its core has turned out to generate high‐quality, standardised data in an effective manner, which facilitates a multitude of analyses. In this paper we provide the current versions of our guidelines, field forms and data entry spreadsheets, as open‐access Online Resources to facilitate the easy implementation of this methodology by other researchers. We also discuss potential future additions and modifications to the approach, among which the most promising are the use of stratified‐random methods to a priori localise the plots and ideas to sample invertebrate taxa on the same plots and grain sizes, such as grasshoppers (Orthoptera) and vegetation‐dwelling spiders (Araneae). As with any other method, the EDGG sampling methodology is not ideal for every single purpose, but with its continuous improvements and its flexibility, it is a good multi‐ purpose approach. A particularly advantageous element, lacking in most other sampling schemes, including classical phytosociogical sampling, is the multi‐scale and multi‐taxon approach, which provides data that allow for deeper understanding of the generalities and idiosyncrasies of biodiversity patterns and their underlying drivers across scales and taxa

Fracture Risk and Use of Angiotensin-Converting Enzyme Inhibitors or Angiotensin II Receptor Blockers

Medications used to treat hypertension may affect fracture risk. This study investigated fracture risk for users of angiotensin converting enzyme inhibitors (ACEI) or angiotensin II receptor blockers (ARB). Participants (899 men, median age 70.3 yr (59.9-79.1), range 50.0-96.6 yr; 574 women, median age 65.5 yr (58.1-75.4), range 50.1-94.6 yr) were from the Geelong Osteoporosis Study. Medication use was self-reported and incident fractures were ascertained using radiological reports. Bone mineral density (BMD) was measured at the femoral neck. Participants were divided into four groups: (1) non-users without hypertension, (2) non-users with hypertension, (3) ACEI users and (4) ARB users. Dosage was calculated using the defined daily dose (DDD) criteria. Participants were followed from date of visit to first fracture, death or 31 December 2016, whichever occurred first. Cox proportional hazards models were used for analyses. At least one incident fracture was sustained by 156 men and 135 women over a median(IQR) of 11.5(6.2-13.2) and 10.9(6.3-11.6) years of follow-up, respectively. In unadjusted analyses, compared to non-users without hypertension, men in all three other groups had a higher risk of fracture (Hazard Ratio (HR, 95%CI) 1.54, 1.00-2.37; 1.90, 1.18-3.05; 2.15, 1.26-3.66), for non-users with hypertension, ACEI and ARB users, respectively). Following adjustment for age, prior fracture and BMD, these associations became non-significant. A dose effect for ARB use was observed; men using lower doses had a higher risk of fracture than non-users without hypertension, in both unadjusted (2.66, 1.34-5.29) and adjusted (2.03, 1.01-4.08) analyses, but this association was not observed at higher doses. For women, unadjusted analyses showed a higher risk for ACEI users compared to non-users without hypertension (1.74, 1.07-2.83). This was explained after adjustment for age, alcohol consumption, prior fracture and BMD (1.28, 0.74-2.22). No other differences were observed. In men, lower dose (0 < DDD ≤ 1) ARB use was associated with an increased risk of fracture. ACEI or ARB use was not associated with increased risk of incident fracture in women. These findings may be important for antihypertensive treatment decisions in individuals with a high risk of fracture. Keywords: Angiotensin II receptor blockers; Angiotensin converting enzyme inhibitors; Fracture risk