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1.
Zootaxa ; 3682: 432-40, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-25243298

RESUMEN

Hydrolutos gransabanensis, a new species of Lutosini (Orthoptera: Anostostomatidae) from the cave Cueva El Tigre (Santa Elena de Uairén, SE Venezuela) is described and figured for both sexes. This is the first record of Hydrolutos species out of tepui systems. The genus is recently known by 6 apterous species from Venezuelan Guayana region.


Asunto(s)
Ortópteros/anatomía & histología , Ortópteros/clasificación , Animales , Ambiente , Femenino , Masculino , Especificidad de la Especie , Venezuela
2.
Plant Signal Behav ; 18(1): 2163065, 2023 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-36635990

RESUMEN

Flower angle is crucially important for accurate pollination and flower protection against abiotic factors. Evolutionary factors shaping floral traits are particularly strong for bilaterally symmetric flowers because these flowers require more pollination accuracy than radially symmetrical flowers. We experimentally investigated the flower angle in the snowdrop's (Galanthus nivalis) radially symmetrical, early-blooming downward flowers. Bumblebees were able to gather significantly more pollen grains from downward flowers than from upward flowers, but female traits (fertility in the field) seem unaffected by flower angle. Similar experiments with radially symmetrical, later flowering Lesser celandine (Ficaria verna) upward flowers showed no differences in bees' abilities to gather pollen in upward vs downward-facing flowers. The downward angle of snowdrop flowers is an adaptation that increases the ability of insects to collect more pollen grains under unfavorable early spring weather conditions when pollinators are scarce.


Asunto(s)
Chelidonium , Animales , Galanthus , Insectos , Polinización , Polen , Flores
3.
Sci Rep ; 13(1): 4969, 2023 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-37041216

RESUMEN

People vary both in their embrace of their society's traditions, and in their perception of hazards as salient and necessitating a response. Over evolutionary time, traditions have offered avenues for addressing hazards, plausibly resulting in linkages between orientations toward tradition and orientations toward danger. Emerging research documents connections between traditionalism and threat responsivity, including pathogen-avoidance motivations. Additionally, because hazard-mitigating behaviors can conflict with competing priorities, associations between traditionalism and pathogen avoidance may hinge on contextually contingent tradeoffs. The COVID-19 pandemic provides a real-world test of the posited relationship between traditionalism and hazard avoidance. Across 27 societies (N = 7844), we find that, in a majority of countries, individuals' endorsement of tradition positively correlates with their adherence to costly COVID-19-avoidance behaviors; accounting for some of the conflicts that arise between public health precautions and other objectives further strengthens this evidence that traditionalism is associated with greater attention to hazards.


Asunto(s)
COVID-19 , Humanos , Pandemias , Motivación , Salud Pública
4.
Insects ; 13(8)2022 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-35893025

RESUMEN

Strong winds, fire, and subsequent forest management impact arthropod communities. We monitored the diversity and changes in the community structure of forest thrips assemblages in the context of secondary succession and anthropogenic impact. There were eight study plots that were affected to varying degrees by the mentioned disturbances that were selected in the Central European spruce (Picea abies (L.) Karst.) forests in Slovakia. The soil photoeclectors were used to obtain thrips in the study plots during two vegetation seasons. The thrips assemblages and their attributes were analyzed by non-metric multidimensional scaling (NMDS). The significant changes in community structure, composition, stratification, species richness, and diversity of thrips assemblages that were caused by natural- (wind) and human-induced disturbance (forestry and fire) were observed in our research. Our analyses revealed a clear relationship between different thrips assemblages and impacted environment. Moreover, our results indicate that silvicolous thrips species may be useful for indicating changes and disturbances in forest ecological systems.

5.
Plant Signal Behav ; 15(11): 1807153, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-32799622

RESUMEN

Flower shapes, colors, sizes and fragrances are shaped mostly for pollinator attraction. Flower phenotypes are, however, subjected to conflicting selection directed by both pollinators and non-pollinating agents. We investigated flower attractiveness to a model pollinator in the snowdrop (Galanthus nivalis L.) under laboratory conditions. Naïve bumblebees (Bombus terrestris L.) showed strong, innate preferences for experimentally altered upward positioned flowers, suggesting that the natural, downward orientation did not evolve to attract pollinators. Experimentally treated green marks on inner tepals decreased pollinator attraction compared with flowers expressing intact marks, suggesting that green marks serve to guide/attract pollinators. Attractiveness of green marks was significantly compromised by flower orientation; green marks were attractive only for untreated downward-oriented flowers, but they did not improve the attractiveness of upward-oriented flowers. Our results suggest that downward flowers in snowdrop evolved under conflicting selection directed by biotic and abiotic factors, and that green marks on inner tepals could evolve later to enhance flower attractiveness.


Asunto(s)
Flores/metabolismo , Flores/fisiología , Galanthus/metabolismo , Galanthus/fisiología , Polinización/fisiología , Evolución Biológica , Odorantes
6.
Zootaxa ; 4066(4): 485-92, 2016 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-27395849

RESUMEN

Hydrolutos piaroa, a new species of Lutosini (Orthoptera: Anostostomatidae) from Tobogán de la Selva (Puerto Ayacucho region, SW Venezuela) is described and figured. Inhabiting aquatic environment it represents an unusual orthopteran with sternal and pleural area covered by fine microtrichia, forming a plastron. This is the first known Hydrolutos species sampled in lowland streams of Venezuelan Guayana.


Asunto(s)
Ortópteros/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Ecosistema , Femenino , Masculino , Tamaño de los Órganos , Ortópteros/anatomía & histología , Ortópteros/crecimiento & desarrollo , Ríos , Venezuela
7.
Behav Processes ; 107: 42-6, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25101561

RESUMEN

Self-grooming is a common behavioural strategy used by various animals to reduce parasite loads. We experimentally tested the adaptive significance of self-grooming model in a sample of Slovak participants. Propensity to self-grooming was activated by visual presence of parasites with verbal information about health risks caused by parasites suggesting that the programmed grooming model works in humans. People who think of themselves as more vulnerable to disease transmission reported higher frequency of self-grooming suggesting that there is a link between the immune system and parasite avoidance behaviour. Considering that the emotion of disgust plays a role in activation of parasite avoidance behaviour, we suggested that knowledge of disgusting stimuli (parasites) would be better retained than knowledge of non-disgusting (hormones), and, thus, non-life-threatening stimuli. As expected, knowledge on parasites tested immediately after the experiment was significantly better than knowledge on hormones suggesting that survival-relevant information is better retained than survival-irrelevant data. However, scores on memory tests did not seem to be influenced by the individual's immune system. Overall, this study showed that self-grooming in humans is functional when disease threat is salient. Human memory systems are tuned to information relevant to survival providing further evidence that human cognition is shaped by natural selection.


Asunto(s)
Susceptibilidad a Enfermedades/psicología , Conocimientos, Actitudes y Práctica en Salud , Higiene , Enfermedades Parasitarias/psicología , Adulto , Animales , Femenino , Humanos , Masculino , Memoria/fisiología , Persona de Mediana Edad , Enfermedades Parasitarias/prevención & control , Adulto Joven
8.
Anthropol Anz ; 70(2): 121-35, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23980387

RESUMEN

Human body morphology is thought to be correlated with sexual behaviour and sociosexuality (defined as an increased willingness to engage in sex without commitment) influences the perception of certain cues of physical attractiveness. Based on a sample of Slovak university students, we investigated relationships between 1) male and female mating success and reported body morphology (body mass index, BMI and waist-to-hip ratio, WHR) and 2) mate preference characteristics and mating success. Both males and females reported a similar number of long-term sexual partners and frequency of engaging in extra-pair copulation (EPC). The mating success of both sexes was positively mediated by self-perceived attractiveness. However, female BMI was inversely associated with mating success whereas increasing BMI was positively associated with male mating success (the total number of lifetime sexual partners) as well as with the likelihood of engaging in EPC. Unrestricted sociosexuality positively correlated with direct and indirect benefits from mating and negatively with the religious/political background of a potential mate and with the desire for a home/ children. These results confirm the hypothesis that human body morphology is associated with sexual behaviour and that cues of direct/indirect benefits in a potential mate positively correlate with sociosexuality.


Asunto(s)
Imagen Corporal , Índice de Masa Corporal , Matrimonio , Conducta Sexual , Adolescente , Adulto , Antropología Física , Femenino , Humanos , Masculino , Eslovaquia , Estadísticas no Paramétricas , Adulto Joven
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