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Human activities are altering ecosystems and threatening the well-being of wildlife. The study of the stressful effects of human disturbances on animal distribution, physiology and behaviour can provide fundamental insights for wildlife conservation. Here, we assess how two declining birds, the European Roller Coracias garrulus and the European Scops Owl Otus scops, cope with alteration by human activities in farming habitats of the south of Spain. We studied nest distribution, quantified nestling physiology (corticosterone levels in plasma and feathers and body weight close to fledgling) and parental behaviour (feeding rates) of both species along a human alteration gradient. Rollers and Scops Owls used the same type of habitat and their spatial distribution was not determined by individual quality. In Rollers, nestlings raised in scrubland areas had high stress-induced corticosterone levels, possibly due to high predation risk in this habitat. In addition, Rollers and Scops Owls showed opposite relationships with farming activity and human disturbance. Nestling Rollers showed the highest corticosterone levels in feathers, weight and parental feeding rates in areas with intense farming activity. These results suggest that despite the disturbance produced by farming activities, inducing a higher stress in these areas, cultivated areas may, simultaneously, provide parents with a higher abundance of prey which would trigger increased feeding rates and, hence, higher nestling weights. Furthermore, nestling Scops Owls showed the highest stress-induced corticosterone levels in areas close to roads, suggesting that they would be affected by human disturbance due to infrastructures that disturb also at night when Scops Owls are active. Therefore, susceptibility to human disturbance may vary between species, probably due to variation in the daily pattern of human activities and the species’ activity rhythm, buffering or exacerbating the effects, which should be considered in future studies on human alterations and birds.
This research communication addresses the hypothesis that in dual-purpose goats, exposure to 1 h of extra-light given from 16 to 17 h after dawn (pulse of light) in winter stimulates milk yield. One group of goats was maintained under natural short photoperiod (natural day; ND (n = 7)). Another group of lactating females was submitted to an artificial long-day photoperiod consisting of 16 h light and 8 h darkness (long days; LD (n = 7)). A third group of females received one single hour of extra-light 16 h after the fixed dawn (pulse of light; PL (n = 6)). Goats from LD and PL yielded 30% more milk than goats from ND. Mean percentages of fat, protein and lactose contents in milk did not differ between the 3 groups at any stage of lactation, but these components in grams/day were higher in goats from PL than in the others two groups within the first 45 d of lactation. In conclusion, dual-purpose lactating goats that started their lactation during natural short days, the daily exposition to a 1-h pulse of light is sufficient to stimulate milk yield compared to females maintained under natural short photoperiod.
The identification of threats to migratory species of conservation concern and the relevance of protected areas for them is often biased towards breeding areas. The European Roller Coracias garrulus is a long-distance migrant experiencing a pronounced decline throughout its breeding range, which has been attributed to the degradation of open agricultural habitats. However, its conservation status in non-breeding areas in Africa remains unstudied. Land cover change is a major threat affecting migratory birds in their wintering grounds, therefore identifying important areas for their protection at this stage is a priority. Here we used occurrence data during the wintering season and ecological niche models to identify key land cover and areas used by Rollers in Africa. First, we used 33 filtered locations from six satellite-tracked birds breeding in Spain to describe suitable wintering areas for the Spanish population (westernmost part of the Eurasian breeding range). We also used 1,167 occurrence data in southern Africa from open-access databases and bird atlases to characterise the overall wintering range of the species. The Spanish population occupied a relatively small area in the north-western part of southern Africa, and a narrow range of land covers. Open grassland, less steep areas and those with sparse tree cover are correlated with suitability. In all, 18.06% of suitable wintering areas for the Spanish population overlapped with protected areas. The overall population of Rollers occupied a wider area and range of land cover. Tree cover was the most important variable affecting suitability, with areas without tree cover being the least suitable. We found that 9.58% of suitable wintering areas for the overall population overlapped with protected areas. Our results suggest that Rollers from different origins (breeding populations) use separate, but overlapping, wintering areas and may have different habitat requirements, and therefore, population-specific conservation strategies in these areas might be needed to fully protect the species.
Thousands of new asteroids are discovered every year and the rate of discovery is by far larger than the determination rate of their physical properties. In 2015 a group of researchers and students of several Mexican institutions have established an observational program to study asteroids photometrically. The program, named Mexican Asteroid Photometry Campaign, is aiming to derive rotation periods of asteroids based on optical photometric observations. Since then four campaigns have been carried out. The results obtained throughout these campaigns, as well as future work, are presented.
Teaching undergraduate students, mentoring graduate students, and generating publishable research are distinct tasks for many political scientists. This article highlights lessons for merging these activities through experiences from an initiative that sparked a series of collaborative-research projects focused on opinions about crime and punishment in the United States. This article describes three collaborative projects conducted between 2015 and 2017 to demonstrate how to merge undergraduate teaching, graduate training, and producing research. By participating in these projects, students learned about social-scientific research through hands-on experiences designing experiments, collecting and analyzing original data, and reporting empirical findings to a public audience. This approach is an effective way to engage students and generate research that can advance professional goals.
The toxicity of water–ethanol extracts of garlic (Allium sativum), ginger (Zingiber officinale), basil (Ocimum basilicum), bitter chaparro (Castela tortuousa), onion (Allium cepa) and papaya (Carica papaya) against adults, eggs and oncomiracidia of Neobenedenia spp. parasites was examined. Parasites were exposed to continuous immersion and treated as follows: extracts were tested at three dilutions: 1:10, 1:50 and 1:100 made with filtered seawater (35 g l–1); ethanol (70%) was evaluated at the same dilutions of 1:10 (7% ethanol), 1:50 (1.4% ethanol) and 1:100 (0.07% ethanol) and a seawater (35 g l–1) control. The antiparasitic effect was measured on: (1) adult survival, egg production and time to detachment from the culture vessel; (2) egg development and cumulative egg hatching; and (3) oncomiracidia survival. All three dilutions of ginger and dilutions 1:100 and 1:50 of basil extract reduced adult survival in vitro, time to detachment from the surface of the culture vessel, egg production and oncomiracidia survival. Bitter chaparro extract reduced adult egg production and oncomiracidia survival. Hatching success was significantly reduced (P < 0.05) in basil extract (1:100) to 86.6% compared to the seawater control (100%). Dilutions 1:10 of ginger and basil exhibited the highest impact on the biological parameters of Neobenedenia sp. Our study demonstrates that water–ethanol extracts of ginger, basil and bitter chaparro are toxic against Neobenedenia sp. life stages.
Animal health surveillance enables the detection and control of animal diseases including zoonoses. Under the EU-FP7 project RISKSUR, a survey was conducted in 11 EU Member States and Switzerland to describe active surveillance components in 2011 managed by the public or private sector and identify gaps and opportunities. Information was collected about hazard, target population, geographical focus, legal obligation, management, surveillance design, risk-based sampling, and multi-hazard surveillance. Two countries were excluded due to incompleteness of data. Most of the 664 components targeted cattle (26·7%), pigs (17·5%) or poultry (16·0%). The most common surveillance objectives were demonstrating freedom from disease (43·8%) and case detection (26·8%). Over half of components applied risk-based sampling (57·1%), but mainly focused on a single population stratum (targeted risk-based) rather than differentiating between risk levels of different strata (stratified risk-based). About a third of components were multi-hazard (37·3%). Both risk-based sampling and multi-hazard surveillance were used more frequently in privately funded components. The study identified several gaps (e.g. lack of systematic documentation, inconsistent application of terminology) and opportunities (e.g. stratified risk-based sampling). The greater flexibility provided by the new EU Animal Health Law means that systematic evaluation of surveillance alternatives will be required to optimize cost-effectiveness.
Control of fire was a hallmark of developing human cognition and an essential technology for the colonisation of cooler latitudes. In Europe, the earliest evidence comes from recent work at the site of Cueva Negra del Estrecho del Río Quípar in south-eastern Spain. Charred and calcined bone and thermally altered chert were recovered from a deep, 0.8-million-year-old sedimentary deposit. A combination of analyses indicated that these had been heated to 400–600°C, compatible with burning. Inspection of the sediment and hydroxyapatite also suggests combustion and degradation of the bone. The results provide new insight into Early Palaeolithic use of fire and its significance for human evolution.
We discuss the mechanism of cluster formation in hierarchically collapsing molecular clouds. Recent evidence, both observational and numerical, suggests that molecular clouds (MCs) may be undergoing global, hierarchical gravitational collapse. The “hierarchical” regime consists of small-scale collapses within larger-scale ones. The latter implies that the star formation rate increases systematically during the early stages of evolution, and occurs via filamentary flows onto “hubs” of higher density, mass, and velocity dispersion, and culminates a few Myr after than the small-scale collapses have started to form stars. In turn, the small-scale collapses occur in clumps embedded in the filaments, and are themselves falling into the larger potential well of the still-ongoing large-scale collapse. The stars formed in the early, small-scale collapses share the infall motion of their parent clumps towards the larger potential trough, so that the filaments feed both gaseous and stellar material to the hubs. This leads to the presence of older stars in a region where new protostars are still forming, to a scale-free or fractal structure of the clusters, in which each unit is composed of smaller-scale ones, and to the eventual merging of the subunits, explaining the observed structural features of open clusters.
International Astronomical Union was formed after the First World War although it became truly international only after the Second World War. Its Commission 41 on History of Astronomy (C41) was set up in 1948 and in a few years established itself as an active and influential unit. It has the distinction of being a joint Commission, the other partner being International Union of History and Philosophy of Science and Technology (IUHPS). Since IAU is an internationally respected body of professional astronomers, its support for history of astronomy enhances the credibility of the discipline in the eyes of scientists as well as science establishments of individual countries. C41 is committed to advancing objective and rigorous world history of astronomy taking into account all its aspects.