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2.
R Soc Open Sci ; 7(5): 200327, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32537227

RESUMEN

After laying their eggs and refilling the egg chamber, sea turtles scatter sand extensively around the nest site. This is presumed to camouflage the nest, or optimize local conditions for egg development, but a consensus on its function is lacking. We quantified activity and mapped the movements of hawksbill (Eretmochelys imbricata) and leatherback (Dermochelys coriacea) turtles during sand-scattering. For leatherbacks, we also recorded activity at each sand-scattering position. For hawksbills, we recorded breathing rates during nesting as an indicator of metabolic investment and compared with published values for leatherbacks. Temporal and inferred metabolic investment in sand-scattering was substantial for both species. Neither species remained near the nest while sand-scattering, instead moving to several other positions to scatter sand, changing direction each time, progressively displacing themselves from the nest site. Movement patterns were highly diverse between individuals, but activity at each sand-scattering position changed little between completion of egg chamber refilling and return to the sea. Our findings are inconsistent with sand-scattering being to directly camouflage the nest, or primarily for modifying the nest-proximal environment. Instead, they are consistent with the construction of a series of dispersed decoy nests that may reduce the discovery of nests by predators.

3.
Br J Sociol ; 70(5): 2133-2165, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31004347

RESUMEN

Perception of Western governments' hostility to Islam is one of the indicating features of Islamic fundamentalism and, in some cases, is serving as a pull to join extremist groups. In this paper, using data from two waves of a cross-national survey, we investigate what affects European Muslims' opinions about Western governments. We find that residential segregation is associated with perceived hostility of Western governments to Islam. Further, we find that Muslims living in segregated neighbourhoods and enclaves have a higher probability of believing that Western governments are hostile to Islam. National origins of Muslim immigrants have a significant impact, with people from African countries measuring less perceived hostility than others. We also find that education is associated with perceived hostility of Western governments to Islam in a non-linear way. People with the highest and lowest levels of education tend to be less likely to believe that Western governments are hostile to Islam, relative to people with mid-level education. This non-linear effect is best explained by education's differential effects on perceptions of key world events. During the time between 2011 - before ISIS's announcement of its Caliphate in Iraq and Syria - and 2013, subsequent to that announcement, we see a sharp decrease in perception of Western governments' hostility to Islam, particularly among more educated European Muslims. We make the case that this decrease can be attributed, in some ways, to the emergence of ISIS. We discuss our findings in terms of theoretical and policy implications.


Asunto(s)
Escolaridad , Hostilidad , Islamismo , Segregación Social , Adolescente , Adulto , Anciano , Europa (Continente) , Femenino , Gobierno , Vivienda , Humanos , Islamismo/psicología , Masculino , Persona de Mediana Edad , Prejuicio , Segregación Social/psicología , Adulto Joven
4.
PLoS One ; 12(2): e0170619, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28199338

RESUMEN

The use of environmental DNA (eDNA) to monitor rare and elusive species has great potential for conservation biology. Traditional surveying methods can be time-consuming, labour-intensive, subject to error or can be invasive and potentially damaging to habitat. The Trinidad golden treefrog (Phytotriades auratus) is one such species that would benefit from such an approach. This species inhabits the giant bromeliad (Glomeropitcairnia erectiflora) on two peaks on the Caribbean island of Trinidad. Traditional survey methods for this species have required the destruction of the giant bromeliad, which is the only known habitat of this frog. Here we described the development of an eDNA PCR-based assay that uses water drawn from the water-filled phytotelmata of the giant bromeliad along with the use of a synthetic DNA positive control that can be easily amplified in the bacterium Escherichia coli. The assay can detect to a DNA concentration of 1.4ng. Sampling of 142 bromeliads using this method revealed 9% were positive for P. auratus DNA. These data suggest that eDNA methods also have great potential for revealing the presence of elusive species in arboreal habitats.


Asunto(s)
Anuros/genética , Bromelia , ADN/genética , Especies en Peligro de Extinción , Reacción en Cadena de la Polimerasa/métodos , Animales , Trinidad y Tobago
5.
Laterality ; 22(6): 641-653, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27666522

RESUMEN

There is considerable debate about the pattern and origin of laterality in forelimb emergence and turning behaviour within amphibians, with the latter being poorly investigated in tadpoles around metamorphic climax. Using 6 species of metamorphosing anurans, we investigated the effect of asymmetrical spiracle location, and disturbance at the time of forelimb emergence, on the pattern of forelimb emergence. Turning behaviour was observed to assess whether motor lateralization occurred in non-neobatrachian anurans and was linked to patterns of forelimb emergence. Biases in forelimb emergence differed among species, supporting the hypothesis that asymmetrical spiracle position results in the same asymmetry in forelimb emergence. However, this pattern only occurred when individuals were undisturbed. Therefore, context at the time of the emergence of the forelimbs may be important, and might explain some discrepancies in the literature. Turning biases, unconnected to forelimb emergence, were found in Pipidae and Bombinatoridae, confirming the basal origin of lateralized behaviour among anurans. Turning direction in our metamorphs differed from the leftward bias commonly observed in tadpoles, but may be analogous to the prevalent right-"handedness" among adult anurans. Therefore, the transitions occurring during metamorphosis may affect lateralized behaviour and metamorphosis may be fruitful for understanding the development of lateralization.


Asunto(s)
Anuros/fisiología , Miembro Anterior , Lateralidad Funcional , Metamorfosis Biológica , Actividad Motora , Animales , Anuros/crecimiento & desarrollo , Conducta Animal , Reacción de Fuga , Miembro Anterior/crecimiento & desarrollo , Miembro Anterior/fisiología , Modelos Lineales , Actividad Motora/fisiología , Especificidad de la Especie
6.
Trends Ecol Evol ; 32(1): 1-3, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27884485

RESUMEN

This paper describes a process of 'open' interdisciplinary scholarship. Researchers from across the University of Oklahoma blogged about a recent paper by ecologist Erle Ellis, and met in person to discuss posts. They then hosted Ellis for a seminar on questions that emerged, and for a public panel discussion.


Asunto(s)
Blogging , Comunicación Interdisciplinaria , Humanos , Investigadores
7.
J Therm Biol ; 51: 15-22, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25965013

RESUMEN

Leatherback turtles (Dermochelys coriacea) are the largest species of marine turtle and the fourth most massive extant reptile. In temperate waters they maintain body temperatures higher than surrounding seawater through a combination of insulation, physiological, and behavioural adaptations. Nesting involves physical activity in addition to contact with warm sand and air, potentially presenting thermal challenges in the absence of the cooling effect of water, and data are lacking with which to understand their nesting thermal biology. Using non-contact methods (thermal imaging and infrared thermometry) to avoid any stress-related effects, we investigated core and surface temperature during nesting. The mean±SE core temperature was 31.4±0.05°C (newly emerged eggs) and was not correlated with environmental conditions on the nesting beach. Core temperature of leatherbacks was greater than that of hawksbill turtles (Eretmochelys imbricata) nesting at a nearby colony, 30.0±0.13°C. Body surface temperatures of leatherbacks showed regional variation, the lateral and dorsal regions of the head were warmest while the carapace was the coolest surface. Surface temperature increased during the early nesting phases, then levelled off or decreased during later phases with the rates of change varying between body regions. Body region, behavioural phase of nesting and air temperature were found to be the best predictors of surface temperature. Regional variation in surface temperature were likely due to alterations in blood supply, and temporal changes in local muscular activity of flippers during the different phases of nesting. Heat exchange from the upper surface of the turtle was dominated by radiative heat loss from all body regions and small convective heat gains to the carapace and front flippers.


Asunto(s)
Regulación de la Temperatura Corporal , Tortugas/fisiología , Adaptación Fisiológica , Animales , Ambiente , Femenino , Comportamiento de Nidificación , Temperatura
8.
Mem Cognit ; 39(8): 1401-8, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21584854

RESUMEN

When people learn an environment, they appear to establish a principle orientation just as they would determine the "top" of a novel object. Evidence for reference orientations has largely come from observations of orientation dependence in pointing judgments: Participants are most accurate when asked to recall the space from a particular orientation. However, these investigations have used highly constrained encoding in both time-scale and navigational goals, leaving open the possibility that larger spaces experienced during navigational learning depend on a different organizational scheme. To test this possibility, we asked undergraduates to perform judgments of relative direction on familiar landmarks around their well-learned campus. Participants showed clear evidence for a single reference orientation, generally aligned along salient axes defined by the buildings and paths. This result argues that representing space involves the establishment of a reference orientation, a requirement that endures over repeated exposures and extensive experience.


Asunto(s)
Memoria a Largo Plazo/fisiología , Recuerdo Mental/fisiología , Orientación/fisiología , Percepción Espacial/fisiología , Adulto , Humanos , Juicio/fisiología , Adulto Joven
9.
BMC Health Serv Res ; 5(1): 29, 2005 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-15829013

RESUMEN

BACKGROUND: It is estimated that approximately half of emergency department (ED) usage in the U.S. and other developed countries is for non-urgent conditions and that this usage is related to availability, social, and economic factors. We examined pediatric ED usage in a U.S. state with respect to income, health insurance status, types of medical conditions, and whether introduction of managed care affected utilization by Medicaid children. METHODS: Emergency department usage rates were calculated from 1996 through 1998 using Utah ED data for children with commercial health insurance, Medicaid, for uninsured children, and by income group estimating neighborhood household income from Zip code of residence. We analyzed usage following the July 1996 transition of Utah Medicaid to managed care. RESULTS: Children with Medicaid had approximately 50% greater ED utilization rates than children with commercial health insurance or uninsured children. The majority of usage for Medicaid and uninsured children was for non-traumatic conditions. Only 35% of total ED usage was for non-emergent or non-urgent conditions and this was related to both Medicaid and low household income. Children lacking health insurance were more likely to be discharged against medical advice (OR = 2.36, 95% C.I. 1.88-2.96). There was no reduction in Medicaid ED usage following the transition to managed care. CONCLUSION: Usage of ED services is related to both health insurance status and income. Children lacking health insurance and Medicaid children have excessive usage for conditions which could be treated in a primary care setting. That managed care does not reduce Medicaid ED usage is consistent with findings of other studies.


Asunto(s)
Servicio de Urgencia en Hospital/estadística & datos numéricos , Mal Uso de los Servicios de Salud/estadística & datos numéricos , Programas Controlados de Atención en Salud/estadística & datos numéricos , Medicaid/estadística & datos numéricos , Adolescente , Niño , Preescolar , Servicio de Urgencia en Hospital/economía , Mal Uso de los Servicios de Salud/economía , Humanos , Renta/clasificación , Lactante , Recién Nacido , Seguro de Salud/estadística & datos numéricos , Pacientes no Asegurados/estadística & datos numéricos , Morbilidad , Características de la Residencia , Factores Socioeconómicos , Utah
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