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1.
Oecologia ; 193(2): 349-358, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32564187

RESUMEN

Understanding how spring phenology influences early life can provide important insights into drivers of future development and survival. We combined unique, long-term data from a bighorn sheep population and satellite-derived phenology indices to quantify the relative importance of maternal and environmental influences on milk composition and lamb overwinter survival. Based on 216 milk samples from 34 females monitored over 6 years, we found that longer snow-free and vegetation growing seasons increased milk fatty acid, iron and lactose concentrations. Structural equation modelling revealed no causality between milk energy content, lamb weaning mass and lamb overwinter survival. Our results suggest that spring conditions can affect milk energy content, but we did not detect any effect on lamb overwinter survival either directly or indirectly through lamb weaning mass. The effect of green-up date on milk composition and energy content suggests that herbivores living in seasonal environments, such as the bighorn sheep, might rely on a strategy intermediate between 'capital' and 'income' breeding when energy demands are high.


Asunto(s)
Mamíferos , Leche , Animales , Cruzamiento , Femenino , Estaciones del Año , Ovinos , Destete
2.
Genes (Basel) ; 11(6)2020 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-32526937

RESUMEN

The severe respiratory disease COVID-19 was initially reported in Wuhan, China, in December 2019, and spread into many provinces from Wuhan. The corresponding pathogen was soon identified as a novel coronavirus named SARS-CoV-2 (formerly, 2019-nCoV). As of 2 May, 2020, over 3 million COVID-19 cases had been confirmed, and 235,290 deaths had been reported globally, and the numbers are still increasing. It is important to understand the phylogenetic relationship between SARS-CoV-2 and known coronaviruses, and to identify its hosts for preventing the next round of emergency outbreak. In this study, we employ an effective alignment-free approach, the Natural Vector method, to analyze the phylogeny and classify the coronaviruses based on genomic and protein data. Our results show that SARS-CoV-2 is closely related to, but distinct from the SARS-CoV branch. By analyzing the genetic distances from the SARS-CoV-2 strain to the coronaviruses residing in animal hosts, we establish that the most possible transmission path originates from bats to pangolins to humans.


Asunto(s)
Betacoronavirus/genética , Infecciones por Coronavirus/transmisión , Coronavirus/genética , Modelos Biológicos , Neumonía Viral/transmisión , Animales , Betacoronavirus/clasificación , Quirópteros/virología , Coronavirus/clasificación , Infecciones por Coronavirus/virología , Cisteína Endopeptidasas/química , Cisteína Endopeptidasas/genética , Brotes de Enfermedades , Reservorios de Enfermedades , Humanos , Mamíferos/clasificación , Mamíferos/virología , Pandemias , Filogenia , Neumonía Viral/virología , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Proteínas no Estructurales Virales/química , Proteínas no Estructurales Virales/genética
3.
J Environ Manage ; 268: 110423, 2020 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-32510423

RESUMEN

Roads increase wildlife mortality and present a movement barrier for many species. While wildlife passages have been advocated as a solution to many of the problems associated with roads, they are expensive and many roads still have none. However, roads usually have a series of drainage culverts designed to allow water to cross underneath the road, which might also be used by some mammals. This study aims to (1) determine what variables influence the number of successful passages of drainage culverts by mammals, and to (2) parse the effects that these variables have on the entry into and subsequent full passage of drainage culverts by individual mammals, using cameras and animal track stations along a 20 km stretch of autoroute 10 in Southern Quebec (Canada). Overall, 20 species were observed outside of the drainage culverts, but only about half of them were detected making full crossings. While various species were often seen outside, only animals highly tolerant to water, including raccoons (Procyon lotor) and American mink (Neovison vison), were observed fully crossing the structures with regularity, whereas the number of full crossings was small (<8) for all other species. High-water levels and use of polyethylene as a construction material were the strongest deterrents for both the number of successful passages and the probability of entry into the culverts. While several variables (e.g., water level, structure material, moon luminosity, distance to forest) influenced culvert entry, none had an influence on a mammal's probability of complete passage once it had entered. The results imply that ordinary drainage culverts are unsuitable as substitutes for designated wildlife passages for mammals. We recommend the installation of designated wildlife passages and fences, and that in places where wildlife passages are not feasible, dry ledges be installed in existing drainage culverts to better allow small and medium-sized mammals to safely cross under roads while avoiding the water inside of the culverts. To our knowledge, this study is the first to successfully combine trail cameras inside of drainage culverts with track-box data in the adjacent habitat.


Asunto(s)
Animales Salvajes , Mamíferos , Animales , Canadá , Ecosistema , Quebec
4.
Nature ; 581(7809): 421-427, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32461642

RESUMEN

The fossil record of mammaliaforms (mammals and their closest relatives) of the Mesozoic era from the southern supercontinent Gondwana is far less extensive than that from its northern counterpart, Laurasia1,2. Among Mesozoic mammaliaforms, Gondwanatheria is one of the most poorly known clades, previously represented by only a single cranium and isolated jaws and teeth1-5. As a result, the anatomy, palaeobiology and phylogenetic relationships of gondwanatherians remain unclear. Here we report the discovery of an articulated and very well-preserved skeleton of a gondwanatherian of the latest age (72.1-66 million years ago) of the Cretaceous period from Madagascar that we assign to a new genus and species, Adalatherium hui. To our knowledge, the specimen is the most complete skeleton of a Gondwanan Mesozoic mammaliaform that has been found, and includes the only postcranial material and ascending ramus of the dentary known for any gondwanatherian. A phylogenetic analysis including the new taxon recovers Gondwanatheria as the sister group to Multituberculata. The skeleton, which represents one of the largest of the Gondwanan Mesozoic mammaliaforms, is particularly notable for exhibiting many unique features in combination with features that are convergent on those of therian mammals. This uniqueness is consistent with a lineage history for A. hui of isolation on Madagascar for more than 20 million years.


Asunto(s)
Fósiles , Islas , Mamíferos/anatomía & histología , Mamíferos/clasificación , Filogenia , Esqueleto/anatomía & histología , Animales , Dentición , Madagascar , Cráneo/anatomía & histología
5.
Parasitol Res ; 119(7): 2093-2104, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32462294

RESUMEN

We studied patterns of ectoparasite species turnover and pairwise ectoparasite-host interactions across space and time in fleas and mites harboured by small mammals using a novel metric, zeta diversity (similarity between multiple communities). We asked whether the zeta diversity of parasites and their interactions with hosts follow a similar spatial or temporal trend. We found substantial differences in some (zeta decline and retention rate) but not in other (zeta decay) spatial patterns of zeta diversity between species and interactions, whereas the differences between the patterns of the temporal species versus interaction zeta diversity occurred to a much lesser extent. In particular, the parametric form of zeta decline suggested that the distribution of ectoparasite species across localities is driven mainly by niche-based processes, whereas the spatial distribution of flea-host and mite-host interactions is predominantly stochastic. We also found much stronger variation in the number of shared species and interactions over space than over time. Parasite community composition, in terms of species, appeared to be much more temporally stable than that in terms of parasite-host interactions. The parametric form of temporal zeta decline indicated that both parasite communities and parasite-host networks are assembled over time via niche-based processes.


Asunto(s)
Infestaciones por Pulgas/parasitología , Interacciones Huésped-Parásitos/fisiología , Mamíferos/parasitología , Infestaciones por Ácaros/parasitología , Distribución Animal , Animales , Infestaciones por Pulgas/epidemiología , Especificidad del Huésped , Infestaciones por Ácaros/epidemiología , Ácaros , Siphonaptera , Factores de Tiempo
6.
Sci Total Environ ; 734: 139473, 2020 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-32464394

RESUMEN

Understanding spatiotemporal patterns of species distributions and their determinants is paramount in ecology. Here, we explore the relationship between the diversity of surviving mammals and two of the main alimentary resources (araucaria seeds and feijoa fruits) across the Araucaria Forest (FOM) in South America. First, we investigated the influence of landscape and environment on the species distribution and pulse of forest productivity. Then, we evaluated how these spatiotemporal pulses in resource availability influence the mammalian diversity. We analyzed the data via diversity descriptors, Morisita index and multiple regressions. Our findings highlighted that climate, tree density, and other environmental variables explained the pulses of productivity. Mammalian diversity of first-order consumers mammals-all those immediately feeding on seeds and fruits-was partially related to resource pulses. Our results revealed that the pulses of forest resources can influence mammal diversity over the years, including delayed responses and asynchronous oscillations. The integrity of vegetal elements of the FOM is key to maintain several mammal-mediated ecological processes. Maintaining the viability of tree populations, encouraging the sustainable use of non-timber resources, and promoting the conservation of the mammalian fauna, which is undergoing an unprecedented diversity crisis worldwide, can help to preserve the remaining ecological processes.


Asunto(s)
Biodiversidad , Mamíferos , Animales , Brasil , Bosques , Árboles
7.
Science ; 368(6493)2020 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-32439765

RESUMEN

The social environment, both in early life and adulthood, is one of the strongest predictors of morbidity and mortality risk in humans. Evidence from long-term studies of other social mammals indicates that this relationship is similar across many species. In addition, experimental studies show that social interactions can causally alter animal physiology, disease risk, and life span itself. These findings highlight the importance of the social environment to health and mortality as well as Darwinian fitness-outcomes of interest to social scientists and biologists alike. They thus emphasize the utility of cross-species analysis for understanding the predictors of, and mechanisms underlying, social gradients in health.


Asunto(s)
Longevidad/fisiología , Mamíferos/fisiología , Determinantes Sociales de la Salud , Animales , Aptitud Genética , Humanos , Longevidad/genética , Mamíferos/genética , Medio Social
9.
Ecol Lett ; 23(6): 1024-1033, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32249475

RESUMEN

Recent studies demonstrate that by focusing on traits linked to fundamental plant life-history trade-offs, ecologists can begin to predict plant community structure at global scales. Yet, consumers can strongly affect plant communities, and means for linking consumer effects to key plant traits and community assembly processes are lacking. We conducted a global literature review and meta-analysis to evaluate whether seed size, a trait representing fundamental life-history trade-offs in plant offspring investment, could predict post-dispersal seed predator effects on seed removal and plant recruitment. Seed size predicted small mammal seed removal rates and their impacts on plant recruitment consistent with optimal foraging theory, with intermediate seed sizes most strongly impacted globally - for both native and exotic plants. However, differences in seed size distributions among ecosystems conditioned seed predation patterns, with relatively large-seeded species most strongly affected in grasslands (smallest seeds), and relatively small-seeded species most strongly affected in tropical forests (largest seeds). Such size-dependent seed predation has profound implications for coexistence among plants because it may enhance or weaken opposing life-history trade-offs in an ecosystem-specific manner. Our results suggest that seed size may serve as a key life-history trait that can integrate consumer effects to improve understandings of plant coexistence.


Asunto(s)
Ecosistema , Dispersión de Semillas , Animales , Mamíferos , Plantas , Conducta Predatoria , Semillas
10.
Zootaxa ; 4743(4): zootaxa.4743.4.2, 2020 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-32230310

RESUMEN

The Danish naturalist Peter Wilhelm Lund (1801-1880), regarded as the father of Brazilian palaeontology and archaeology, is known mainly for his work with fossil mammals of Quaternary age from the limestone caves of the Lagoa Santa region in the state of Minas Gerais, southeastern Brazil. However, during one decade of fieldwork (1835-1844), he also collected a large number of remains of other animal groups from these caves. Birds were well represented and, following assessment by the Danish ornithologist Oluf Winge (1855-1889), most of the specimens collected by Lund belong to species still living in the area. Here we present an overview of the bird remains (fossil and recent), found by Lund and others in the region, we update their taxonomic attributions, and comment on the history of the material, making information previously published only in Danish available in English.


Asunto(s)
Aves , Fósiles , Animales , Cuevas , Masculino , Mamíferos
11.
J Environ Manage ; 262: 110313, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32250796

RESUMEN

In an attempt to improve cost-effectiveness, it has become increasingly popular to adapt wildlife crossing structures to enable people to also use them for safe passage across roads. However, the required needs of humans and wildlife may conflict, resulting in a structure that does not actually provide the perceived improvement in cost-effectiveness, but instead a reduction in conservation benefits. For example, lighting within crossing structures for human safety at night may reduce use of the structure by nocturnal wildlife, thus contributing to barrier and mortality effects of roads rather than mitigating them. In this study, we experimentally evaluated the impact of artificial light at night on the rate of use of wildlife crossing structures, specifically underpasses, by ten insectivorous bat species groups in south-eastern Australia. We monitored bat activity before, during and after artificially lighting the underpasses. We found that bats tended to avoided lit underpasses, and only one species consistently showed attraction to the light. Artificial light at night in underpasses hypothetically increases the vulnerability of bats to road-mortality or to the barrier effect of roads. The most likely outcomes of lighting underpasses were 1. an increase in crossing rate above the freeway and a decrease under the underpasses, or 2. a reduction in crossing rate both above freeways and under the underpasses, when structures were lit. Our results corroborate those of studies on terrestrial mammals, and thus we recommend that underpasses intended to facilitate the movement of wildlife across roads should not be lit.


Asunto(s)
Quirópteros , Animales , Animales Salvajes , Humanos , Iluminación , Mamíferos , Australia del Sur
12.
Oecologia ; 192(4): 1057-1071, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32248505

RESUMEN

We studied compositional turnover in communities of fleas and mites harboured by small mammals using zeta diversity metric (similarity between multiple communities) and asked whether the patterns of zeta diversity decline with an increase in the number of communities differ between taxa and hierarchical scales [infracommunities (parasite assemblages on individual hosts), component communities (parasite assemblages harboured by host populations), and compound communities (all parasite species in a locality)]. The average number of shared species declined with an increasing number of communities (zeta order). It attained zero at higher orders in infracommunities of both taxa with the shape of the zeta decline being best fitted by the negative exponential function, and the retention rate curves being modal. In contrast, zeta diversity values for compound communities of mites and fleas did not attain zero at higher zeta orders, and the form of the zeta decline was best fitted by the power-law function, whereas the retention rate curves were asymptotic. In component communities, the form of zeta decline was best fitted by either exponential or power-law function in dependence of whether communities were considered within a host across localities or across hosts within a locality and whether ubiquitous species were taken into account. Our main conclusions are that (a) the rules governing compositional turnover in parasite communities for the lowest and the highest hierarchical scales are taxon-invariant but scale-dependent and (b) species composition of infracommunities is mainly driven by stochastic assembly processed, whereas that of compound communities is mainly driven by niche-based processes.


Asunto(s)
Infestaciones por Pulgas , Ácaros , Parásitos , Siphonaptera , Animales , Interacciones Huésped-Parásitos , Mamíferos
13.
Nature ; 580(7801): 87-92, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32238927

RESUMEN

Southern Ocean ecosystems are under pressure from resource exploitation and climate change1,2. Mitigation requires the identification and protection of Areas of Ecological Significance (AESs), which have so far not been determined at the ocean-basin scale. Here, using assemblage-level tracking of marine predators, we identify AESs for this globally important region and assess current threats and protection levels. Integration of more than 4,000 tracks from 17 bird and mammal species reveals AESs around sub-Antarctic islands in the Atlantic and Indian Oceans and over the Antarctic continental shelf. Fishing pressure is disproportionately concentrated inside AESs, and climate change over the next century is predicted to impose pressure on these areas, particularly around the Antarctic continent. At present, 7.1% of the ocean south of 40°S is under formal protection, including 29% of the total AESs. The establishment and regular revision of networks of protection that encompass AESs are needed to provide long-term mitigation of growing pressures on Southern Ocean ecosystems.


Asunto(s)
Sistemas de Identificación Animal , Organismos Acuáticos/fisiología , Cambio Climático/estadística & datos numéricos , Conservación de los Recursos Naturales/métodos , Ecosistema , Océanos y Mares , Conducta Predatoria , Animales , Regiones Antárticas , Biodiversidad , Aves , Peces , Cadena Alimentaria , Cubierta de Hielo , Mamíferos , Dinámica Poblacional
14.
PLoS One ; 15(3): e0230192, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32226036

RESUMEN

While movement patterns of grazing ungulates are strongly dependent on forage quality their use of nutrient hotspots such as termite mounds or grazing lawns has rarely been quantified, especially in savanna ecosystems where soil-nutrient quality is low. Additionally, few experiments have been conducted to determine the role of termite mound- and grazing lawn-derived soils in improving forage quality in the field. We studied wild ungulate grazing activities around ten termite mounds, six grazing lawns and their respective control sites in a Miombo system of Issa Valley, western Tanzania, in the same system. We used indirect observations (i.e., dung, tracks) to identify seasonal and spatial variations in habitat use of various wild mammalian grazers. Grazer visitation rates were nine and three times higher on termite mounds and grazing lawns, respectively, compared to control sites. During the rainy season, termite mounds were more frequently used than grazing lawns while the latter were used more often during the dry season. In an additional pot experiment with soils derived from different areas, we found that Cynodon dactylon in termite mound-derived soils had twice as high Nitrogen and Phosphorous contents and biomass compared to grasses planted in grazing lawn soils and control site soils. We highlight that both termite mounds and grazing lawns play a significant role in influencing seasonal nutrient dynamics, forage nutrient quality, habitat selectivity, and, hence, grazing activities and movement patterns of wild ungulate grazers in savannas. We conclude that termite mounds and grazing lawns are important for habitat heterogeneity in otherwise nutrient-poor savanna systems.


Asunto(s)
Cynodon/química , Nutrientes/química , Poaceae/química , Animales , Biomasa , Ecosistema , Conducta Alimentaria/fisiología , Pradera , Isópteros/química , Mamíferos , Nitrógeno/química , Fósforo/química , Plantas/química , Estaciones del Año , Suelo/química , Tanzanía
16.
Ecotoxicol Environ Saf ; 196: 110487, 2020 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-32229327

RESUMEN

Despite numerous investigations into AgNP-induced toxicity, little has been taken into consideration the potential health impacts of aged AgNPs in comparison to fresh AgNPs. In the current study, we scrutinized the potential effects of aged AgNPs in animals. We first found that AgNPs underwent morphological transformations after natural ageing in aqueous solution upon exposure to air and sunlight for 9 days, as characterized by significant aggregation with increase of particle size approximately by 2 fold. Meanwhile, dissolved Ag ions from aged AgNPs increased by 33% compared to fresh AgNPs. Strikingly, the acute exposure results showed that aged AgNPs induced lower toxicity in mice relative to fresh AgNPs. Aged AgNPs caused milder local inflammation in the peritoneal cavity of mice, as evidenced by 63% reduction of tumor necrosis factor α (TNF-α) than that induced by fresh AgNPs. The deposition mass of aged AgNPs in the liver, spleen, lung and kidney was diminished by 69%, 39%, 83% and 40%, respectively, compared to the distribution profiles in response to fresh AgNPs. Whereby, milder splenic hyperemia was observed, and no significant hepatoxicity was found. Additionally, aged AgNPs provoked milder increase of periphery leukocytes and malondialdehyde (MDA) in mice in comparison to fresh AgNPs. Taken together, this study unraveled that the ageing process elicited remarkable alterations to physicochemical properties and toxic effects as well. This study would provide new insights into the potential health impacts of AgNPs under transformation-determined exposure scenarios.


Asunto(s)
Nanopartículas del Metal/química , Nanopartículas del Metal/toxicidad , Plata/química , Plata/toxicidad , Animales , Mamíferos , Nanopartículas del Metal/efectos de la radiación , Ratones , Tamaño de la Partícula , Plata/metabolismo , Plata/efectos de la radiación , Luz Solar , Distribución Tisular , Pruebas de Toxicidad Aguda , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/efectos de la radiación , Contaminantes Químicos del Agua/toxicidad
17.
Nat Chem Biol ; 16(4): 379-382, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32198493

RESUMEN

Tyrosine sulfation is an important post-translational modification found in higher eukaryotes. Here we report an engineered tyrosyl-tRNA synthetase/tRNA pair that co-translationally incorporates O-sulfotyrosine in response to UAG codons in Escherichia coli and mammalian cells. This platform enables recombinant expression of eukaryotic proteins homogeneously sulfated at chosen sites, which was demonstrated by expressing human heparin cofactor II in mammalian cells in different states of sulfation.


Asunto(s)
Ingeniería de Proteínas/métodos , Somatomedinas/química , Tirosina/análogos & derivados , Animales , Codón de Terminación/metabolismo , Escherichia coli/metabolismo , Código Genético , Cofactor II de Heparina/metabolismo , Humanos , Mamíferos , Procesamiento Proteico-Postraduccional , Proteínas/química , Tirosina/química , Tirosina-ARNt Ligasa/metabolismo
18.
PLoS One ; 15(3): e0230209, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32160257

RESUMEN

Agricultural frontier expansion into the Amazon over the last four decades has created million hectares of fragmented forests. While many species undergo local extinctions within remaining forest patches, this may be compensated by native species from neighbouring open-habitat areas potentially invading these patches, particularly as forest habitats become increasingly degraded. Here, we examine the effects of habitat loss, fragmentation and degradation on small mammal assemblages in a southern Amazonian deforestation frontier, while accounting for species-specific degree of forest-dependency. We surveyed small mammals at three continuous forest sites and 19 forest patches of different sizes and degrees of isolation. We further sampled matrix habitats adjacent to forest patches, which allowed us to classify each species according to forest-dependency and generate a community-averaged forest-dependency index for each site. Based on 21,568 trap-nights, we recorded 970 small mammals representing 20 species: 12 forest-dependents, 5 matrix-tolerants and 3 open-habitat specialists. Across the gradient of forest patch size, small mammal assemblages failed to show the typical species-area relationship, but this relationship held true when either species abundance or composition was considered. Species composition was further mediated by community-averaged forest-dependency, so that smaller forest patches were occupied by a lower proportion of forest-dependent rodents and marsupials. Both species richness and abundance increased in less isolated fragments surrounded by structurally simplified matrix habitats (e.g. active or abandoned cattle pastures). While shorter distances between forest patches may favour small mammal abundances, forest area and matrix complexity dictated which species could persist within forest fragments according to their degree of forest-dependency. Small mammal local extinctions in small forest patches within Amazonian deforestation frontiers are therefore likely offset by the incursion of open-habitat species. To preclude the dominance of those species, and consequent losses of native species and associated ecosystem functions, management actions should limit or reduce areas dedicated to pasture, additionally maintaining more structurally complex matrix habitats across fragmented landscapes.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales/tendencias , Mamíferos , Animales , Brasil , Ecosistema , Especies en Peligro de Extinción/tendencias , Bosques , Dinámica Poblacional , Bosque Lluvioso , Ríos , Especificidad de la Especie , Árboles
19.
Nat Ecol Evol ; 4(4): 639-651, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32203472

RESUMEN

Amniotes, such as mammals and reptiles, have vision and other senses represented in the pallium, whereas anamniotes, such as amphibians, fish and cyclostomes (including lampreys), which diverged much earlier, were historically thought to process olfactory information predominantly or even exclusively in the pallium. Here, we show that there is a separate visual area with retinotopic representation, and that somatosensory information from the head and trunk is represented in an adjacent area in the lamprey pallial cortex (lateral pallium). These cortical sensory areas flank a non-primary-sensory motor area. Both vision and somatosensation are relayed via the thalamus. These findings suggest that the basic sensorimotor representation of the mammalian neocortex, as well as the sensory thalamocortical relay, had already evolved in the last common ancestor of cyclostomes and gnathostomes around 560 million years ago.


Asunto(s)
Evolución Biológica , Vertebrados , Animales , Lampreas , Mamíferos , Reptiles
20.
PLoS One ; 15(3): e0230509, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32218604

RESUMEN

Vegetative parts of bilberry (Vaccinium myrtillus) are important forage for many boreal forest mammal, bird and insect species. Plant palatability to insects is affected by concentration of nutrients and defense compounds in plants. We expected that palatability of bilberry leaves to insect herbivores is influenced by light availability and soil productivity (both affecting nitrogen concentration and constitutive carbon-based defense compound concentration) and herbivory by mammals (affecting nitrogen concentration and induced carbon-based defense compound concentration). We studied bilberry leaf herbivory under different light availability, soil productivity and mammalian herbivory pressure in small sampling units (1m x 1m) in boreal forest in Norway. We used generalized linear mixed models and generalized additive mixed models to model insect herbivory on bilberry leaves as a function of shade, soil productivity and mammalian herbivory. Observed insect herbivory on bilberry leaves increased with increasing shade levels. Predicted insect herbivory increased with increasing previous mammalian herbivory at high shade levels and this response was magnified at higher soil productivity levels. At low to intermediate shade levels, this response was only present under high soil productivity levels. Our results indicate that light availability is more important for variation in bilberry leaf palatability than soil nutrient conditions.


Asunto(s)
Herbivoria/fisiología , Insectos/fisiología , Mamíferos/fisiología , Modelos Biológicos , Hojas de la Planta/crecimiento & desarrollo , Suelo , Luz Solar , Vaccinium myrtillus/crecimiento & desarrollo , Animales
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