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1.
Elife ; 102021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34844669

RESUMO

Dinosaur bonebeds with amber content, yet scarce, offer a superior wealth and quality of data on ancient terrestrial ecosystems. However, the preserved palaeodiversity and/or taphonomic characteristics of these exceptional localities had hitherto limited their palaeobiological potential. Here, we describe the amber from the Lower Cretaceous dinosaur bonebed of Ariño (Teruel, Spain) using a multidisciplinary approach. Amber is found in both a root layer with amber strictly in situ and a litter layer mainly composed of aerial pieces unusually rich in bioinclusions, encompassing 11 insect orders, arachnids, and a few plant and vertebrate remains, including a feather. Additional palaeontological data-charophytes, palynomorphs, ostracods- are provided. Ariño arguably represents the most prolific and palaeobiologically diverse locality in which fossiliferous amber and a dinosaur bonebed have been found in association, and the only one known where the vast majority of the palaeontological assemblage suffered no or low-grade pre-burial transport. This has unlocked unprecedentedly complete and reliable palaeoecological data out of two complementary windows of preservation-the bonebed and the amber-from the same site.


Assuntos
Âmbar , Dinossauros , Fósseis , Animais , Biodiversidade , Florestas , Solo , Espanha , Áreas Alagadas
2.
One Health ; 13: 100315, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34485672

RESUMO

West Nile Virus (WNV) has recently emerged as a major public health concern in Europe; its recent expansion also coincided with some remarkable socio-economic and environmental changes, including an economic crisis and some of the warmest temperatures on record. Here we empirically investigate the drivers of this phenomenon at a European wide scale by constructing and analyzing a unique spatial-temporal data-set, that includes data on climate, land-use, the economy, and government spending on environmental related sectors. Drivers and risk factors of WNV were identified by building a conceptual framework, and relationships were tested using a Generalized Additive Model (GAM), which could capture complex non-linear relationships and also account for spatial and temporal auto-correlation. Some of the key risk factors identified in our conceptual framework, such as a higher percentage of wetlands and arable land, climate factors (higher summer rainfall and higher summer temperatures) were positive predictors of WNV infections. Interestingly, winter temperatures of between 2 °C and 6 °C were among some of the strongest predictors of annual WNV infections; one possible explanation for this result is that successful overwintering of infected adult mosquitoes (likely Culex pipiens) is key to the intensity of outbreaks for a given year. Furthermore, lower surface water extent over the summer is also associated with more intense outbreaks, suggesting that drought, which is known to induce positive changes in WNV prevalence in mosquitoes, is also contributing to the upward trend in WNV cases in affected regions. Our indicators representing the economic crisis were also strong predictors of WNV infections, suggesting there is an association between austerity and cuts to key sectors, which could have benefited vector species and the virus during this crucial period. These results, taken in the context of recent winter warming due to climate change, and more frequent droughts, may offer an explanation of why the virus has become so prevalent in Europe.

3.
PLoS One ; 16(1): e0245527, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33513188

RESUMO

The invasive wasp-mimicking Tiger Longicorn Beetle, Xylotrechus chinensis, a potentially lethal pest of mulberry trees (Moraceae: Morus sp.), was first reported in Europe in 2018, although its colonization and establishment were estimated to have occurred during the year 2012 or earlier. In Catalonia the infestation spread from four towns and 44.1 km2 in 2018 to 12 towns and 378.1 km2 in 2020; in the studied town of Barberà del Vallès, infested trees rose from 16.21% in February 2016 to 59.29% in December 2018. Human safety in public parks and avenues is a concern, as beetle infestation increases the risk of falling branches. The main objective of this study was to evaluate how the infestation progresses over time, with and without abamectin treatment, and provide insights into female egg-laying preferences. Such knowledge helps contribute to management efforts to reduce expansion of the range of beetle infestation. Our statistical analysis shows that females prefer laying eggs on larger trees, on the highest part of trunks and on the crown base (this being more preferred than the trunk), and they do so on warmer, SW orientations rather than those facing N, NW and E. Emergence holes and gallery slits predict the spreading of infestations to new trees. An abamectin treatment (trunk injection) carried out at the end of April significantly reduced the number of new infestation. However, for maximum insecticide efficiency, the best time for treating with abamectin would be from mid-July to mid-August, when newly hatched larvae begin feeding on the phloem.


Assuntos
Besouros , Controle de Insetos/estatística & dados numéricos , Inseticidas , Espécies Introduzidas , Ivermectina/análogos & derivados , Morus , Animais , Europa (Continente) , Morus/anatomia & histologia , Morus/crescimento & desenvolvimento , Avaliação de Resultados em Cuidados de Saúde
4.
Int J Health Geogr ; 19(1): 44, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-33138827

RESUMO

BACKGROUND: This study examines the impact of climate, socio-economic and demographic factors on the incidence of dengue in regions of the United States and Mexico. We select factors shown to predict dengue at a local level and test whether the association can be generalized to the regional or state level. In addition, we assess how different indicators perform compared to per capita gross domestic product (GDP), an indicator that is commonly used to predict the future distribution of dengue. METHODS: A unique spatial-temporal dataset was created by collating information from a variety of data sources to perform empirical analyses at the regional level. Relevant regions for the analysis were selected based on their receptivity and vulnerability to dengue. A conceptual framework was elaborated to guide variable selection. The relationship between the incidence of dengue and the climate, socio-economic and demographic factors was modelled via a Generalized Additive Model (GAM), which also accounted for the spatial and temporal auto-correlation. RESULTS: The socio-economic indicator (representing household income, education of the labour force, life expectancy at birth, and housing overcrowding), as well as more extensive access to broadband are associated with a drop in the incidence of dengue; by contrast, population growth and inter-regional migration are associated with higher incidence, after taking climate into account. An ageing population is also a predictor of higher incidence, but the relationship is concave and flattens at high rates. The rate of active physicians is associated with higher incidence, most likely because of more accurate reporting. If focusing on Mexico only, results remain broadly similar, however, workforce education was a better predictor of a drop in the incidence of dengue than household income. CONCLUSIONS: Two lessons can be drawn from this study: first, while higher GDP is generally associated with a drop in the incidence of dengue, a more granular analysis reveals that the crucial factors are a rise in education (with fewer jobs in the primary sector) and better access to information or technological infrastructure. Secondly, factors that were shown to have an impact of dengue at the local level are also good predictors at the regional level. These indices may help us better understand factors responsible for the global distribution of dengue and also, given a warming climate, may help us to better predict vulnerable populations on a larger scale.


Assuntos
Dengue , Clima , Dengue/diagnóstico , Dengue/epidemiologia , Humanos , Incidência , México/epidemiologia , Fatores Socioeconômicos , Estados Unidos/epidemiologia
5.
Insects ; 9(2)2018 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-29747428

RESUMO

In this paper, the invasion of a new alien beetle species to Europe, the longhorn Xylotrechus chinensis (Chevrolat) (Cerambycidae), originating from East Asia, is revealed. It has settled in Catalonia (Spain), occupying at present an area of at least 44.1 km², where it has been shown to severely infest (ca. 10 to 45%) and eventually kill mulberry trees in private and public grounds. The main objective of this study was to evaluate its impact and provide new significant insights into its life history, seasonality, reproductive capacity (females produce an average of 83.4 ± 9.02 eggs) and the type of damage produced to mulberries. Such damage was thoroughly described to facilitate inspection by others. At least in laboratory conditions, X. chinensis has not used common grape vines as an alternative hostplant. Both plants, mulberries and grape vines, are important in Catalonia and Spain, the former providing shade and ornament to many streets and avenues, and the latter having great economic significance in Mediterranean wine production areas. Possible control methods to hinder its spread are suggested and one local wasp, Stephanus serrator (Stephanidae), was identified as a likely parasitoid. We believe the risk of this beetle widely spreading in Europe is very real.

6.
PLoS One ; 12(2): e0171166, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28178286

RESUMO

Castniid moths (Lepidoptera: Castniidae) display a butterfly-like reproductive behavior, i.e., they use visual stimuli for mate location and females have apparently lost their pheromone glands in an evolutionary context. In this paper we report for the first time the identification of three new compounds, namely n-octadecyl acetate, (Z)-9-octadecenyl acetate and (E,Z)-2,13-octadecadienyl acetate, in males of the Castniid Palm Borer, Paysandisia archon, which could be involved in its short-range courtship behavior, and also shed light on recent controversies on the sexual behavior of the species. The compounds are produced in a ring-shaped gland of the male terminalia and have occasionally been detected in very minor amounts (ng) in ovipositor extracts of females, but only while mating or just after copulation. We also report that males use the already known (E,Z)-2,13-octadecadienol to mark their territory by rubbing their midlegs against the upper side of nearby leaves, especially palm leaves. This compound, produced in large amounts, is mostly concentrated in the midleg basitarsi and its maximum production is detected on the sexually mature 1-day-old specimens. In addition, analysis of male wings extracts confirms the presence of Z,E and E,E-farnesals, which are mostly produced in the median band of hindwings of 48-53 h-old insects. The biological significance of farnesals in this species is unknown. Our results point out that the chemical communication of P. archon relies mostly on males, which appear to bear all chemical burden in this respect.


Assuntos
Comunicação Animal , Mariposas , Comportamento Sexual Animal , Animais , Comportamento Animal , Feminino , Masculino , Oviposição , Reprodução , Atrativos Sexuais , Asas de Animais
7.
Parasit Vectors ; 7: 223, 2014 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-24884950

RESUMO

BACKGROUND: Biting midges of the genus Culicoides (Diptera: Ceratopogonidae) are biological vectors of internationally important arboviruses. To understand the role of Culicoides in the transmission of these viruses, it is essential to correctly identify the species involved. Within the western Palaearctic region, the main suspected vector species, C. obsoletus, C. scoticus, C. dewulfi and C. chiopterus, have similar wing patterns, which makes it difficult to separate and identify them correctly. METHODS: In this study, designed as an inter-laboratory ring trial with twelve partners from Europe and North Africa, we assess four PCR-based assays which are used routinely to differentiate the four species of Culicoides listed above. The assays based on mitochondrial or ribosomal DNA or microarray hybridisation were tested using aliquots of Culicoides DNA (extracted using commercial kits), crude lysates of ground specimens and whole Culicoides (265 individuals), and non-Culicoides Ceratopogonidae (13 individuals) collected from across Europe. RESULTS: A total of 800 molecular assays were implemented. The in-house assays functioned effectively, although specificity and sensitivity varied according to the molecular marker and DNA extraction method used. The Obsoletus group specificity was overall high (95-99%) while the sensitivity varied greatly (59.6-100%). DNA extraction methods impacted the sensitivity of the assays as well as the type of sample used as template for the DNA extraction. CONCLUSIONS: The results are discussed in terms of current use of species diagnostic assays and the future development of molecular tools for the rapid differentiation of cryptic Culicoides species.


Assuntos
Ceratopogonidae/genética , DNA/genética , Reação em Cadeia da Polimerase/métodos , Animais , Ceratopogonidae/classificação , Ceratopogonidae/fisiologia , Feminino , Masculino , Sensibilidade e Especificidade , Especificidade da Espécie
8.
PLoS One ; 7(1): e29282, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22238600

RESUMO

BACKGROUND: In the course of evolution butterflies and moths developed two different reproductive behaviors. Whereas butterflies rely on visual stimuli for mate location, moths use the 'female calling plus male seduction' system, in which females release long-range sex pheromones to attract conspecific males. There are few exceptions from this pattern but in all cases known female moths possess sex pheromone glands which apparently have been lost in female butterflies. In the day-flying moth family Castniidae ("butterfly-moths"), which includes some important crop pests, no pheromones have been found so far. METHODOLOGY/PRINCIPAL FINDINGS: Using a multidisciplinary approach we described the steps involved in the courtship of P. archon, showing that visual cues are the only ones used for mate location; showed that the morphology and fine structure of the antennae of this moth are strikingly similar to those of butterflies, with male sensilla apparently not suited to detect female-released long range pheromones; showed that its females lack pheromone-producing glands, and identified three compounds as putative male sex pheromone (MSP) components of P. archon, released from the proximal halves of male forewings and hindwings. CONCLUSIONS/SIGNIFICANCE: This study provides evidence for the first time in Lepidoptera that females of a moth do not produce any pheromone to attract males, and that mate location is achieved only visually by patrolling males, which may release a pheromone at short distance, putatively a mixture of Z,E-farnesal, E,E-farnesal, and (E,Z)-2,13-octadecadienol. The outlined behavior, long thought to be unique to butterflies, is likely to be widespread in Castniidae implying a novel, unparalleled butterfly-like reproductive behavior in moths. This will also have practical implications in applied entomology since it signifies that the monitoring/control of castniid pests should not be based on the use of female-produced pheromones, as it is usually done in many moths.


Assuntos
Comportamento Animal/fisiologia , Borboletas/fisiologia , Evolução Molecular , Mariposas/genética , Mariposas/fisiologia , Atrativos Sexuais/genética , Animais , Borboletas/genética , Corte , Feminino , Deleção de Genes , Masculino , Modelos Biológicos , Filogenia , Reprodução/genética , Reprodução/fisiologia , Atrativos Sexuais/metabolismo , Comportamento Sexual Animal/fisiologia
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