Search results for "stat"
showing 10 items of 29383 documents
Opportunity costs resulting from scramble competition within the choosy sex severely impair mate choosiness.
2016
12 pages; International audience; Studies on mate choice mainly focus on the evolution of signals that would maximize the probability of finding a good-quality partner. Most models of sexual selection rely on the implicit assumption that individuals can freely compare and spot the best mates in a heterogeneous population. Comparatively few studies have investigated the consequences of the mate-sampling process. Several sampling strategies have been studied from theoretical or experimental perspectives. They belong to two families of decision rules: best-of-n strategies (individuals sample n partners before choosing the best one within this pool) or threshold strategies (individuals sequenti…
Extended winters entail long-term costs for insect offspring reared in an overwinter burrow
2018
International audience; Winter imposes an ecological challenge to animals living in colder climates, especially if these adverse conditions coincide with reproduction and offspring rearing. To overcome this challenge, some insects burrow in the soil to protect adults, larvae, or eggs from negative effects of winter. However, whether this protection is effective against any long-term consequences of changes in winter duration is unclear. Here, we investigated the long-term effects of winter length variation on eggs of the European earwig Forficula auricularia. In this insect, females construct and maintain a burrow between late autumn and spring, in which they provide extensive forms of care…
Micromeria rodriguezii (Lamiaceae) en la flora peninsular ibérica
2020
Micromeria rodriguezii es una especie endémica de las Islas Baleares (Mediterráneo occidental). Una población de esta especie se ha encontrado en la provincia de Castellón (España), en el margen de un camino forestal. Se proporciona un estudio de la morfología de las plantas de esta población, así como su estado de conservación en la Comunidad Valenciana. Debido a que esta es la única población ibérica conocida hasta el momento, se debe elaborar un plan de manejo y conservación para garantizar su conservación.
Molecular phylogeny and forms of photosynthesis in tribe Salsoleae (Chenopodiaceae).
2016
Evolution of C3–C4 intermediate and C4 lineages are resolved in Salsoleae (Chenopodiaceae), and a model for structural and biochemical changes for the evolution of the Salsoloid form of C4 is considered.
Low but contrasting neutral genetic differentiation shaped by winter temperature in European great tits.
2016
Gene flow is usually thought to reduce genetic divergence and impede local adaptation by homogenising gene pools between populations. However, evidence for local adaptation and phenotypic differentiation in highly mobile species, experiencing high levels of gene flow, is emerging. Assessing population genetic structure at different spatial scales is thus a crucial step towards understanding mechanisms underlying intraspecific differentiation and diversification. Here, we studied the population genetic structure of a highly mobile species - the great tit Parus major - at different spatial scales. We analysed 884 individuals from 30 sites across Europe including 10 close-by sites (< 50 km), u…
Some like it cold: the glossiphoniid parasites of the Sicilian endemic pond turtle Emys trinacris (Testudines, Emydidae), an example of ‘parasite ine…
2016
The freshwater turtles of the genus Emys and some leech species of the family Glossiphoniidae are the only Palaearctic representatives of primarily Nearctic taxa, which jointly colonized Eurasia and the Maghreb during the Miocene. The strict trophic relationships occurring between the glossiphoniid parasite leech Placobdella costata and its host, the emydid Emys orbicularis, make them a prime example of host–parasite cophylogenetic evolution. In the light of the discovery of the Sicilian cryptic endemic species Emys trinacris, which is the sister species to the widespread Palaearctic E. orbicularis, the possible cophylogenetic divergence of the turtle hosts and their leech parasites was inv…
Experimental approaches for testing if tolerance curves are useful for predicting fitness in fluctuating environments
2017
Most experimental studies on adaptation to stressful environments are performed under conditions that are rather constant and rarely ecologically relevant. Fluctuations in natural environmental conditions are ubiquitous and include for example variation in intensity and duration of temperature, droughts, parasite loads, and availability of nutrients, predators and competitors. The frequency and amplitude of many of these fluctuations are expected to increase with climate change. Tolerance curves are often used to describe fitness components across environmental gradients. Such curves can be obtained by assessing performance in a range of constant environmental conditions. In this perspectiv…
Whole genome sequencing data and de novo draft assemblies for 66 teleost species
2017
Teleost fishes comprise more than half of all vertebrate species, yet genomic data are only available for 0.2% of their diversity. Here, we present whole genome sequencing data for 66 new species of teleosts, vastly expanding the availability of genomic data for this important vertebrate group. We report on de novo assemblies based on low-coverage (9–39×) sequencing and present detailed methodology for all analyses. To facilitate further utilization of this data set, we present statistical analyses of the gene space completeness and verify the expected phylogenetic position of the sequenced genomes in a large mitogenomic context. We further present a nuclear marker set used for phylogenetic…
Energy intake functions and energy budgets of ectotherms and endotherms derived from their ontogenetic growth in body mass and timing of sexual matur…
2017
Abstract Ectothermic and endothermic vertebrates differ not only in their source of body temperature (environment vs. metabolism), but also in growth patterns, in timing of sexual maturation within life, and energy intake functions. Here, we present a mathematical model applicable to ectothermic and endothermic vertebrates. It is designed to test whether differences in the timing of sexual maturation within an animal's life (age at which sexual maturity is reached vs. longevity) together with its ontogenetic gain in body mass (growth curve) can predict the energy intake throughout the animal's life (food intake curve) and can explain differences in energy partitioning (between growth, repro…
Infestation of broad bean (Vicia faba) by the green stink bug (Nezara viridula) decreases shoot abscisic acid contents under well-watered and drought…
2017
The response of broad bean (Vicia faba) plants to water stress alone and in combination with green stink bug (Nezara viridula) infestation was investigated through measurement of: (1) leaf gas exchange; (2) plant hormone titres of abscisic acid (ABA) and its metabolites, and of salicylic acid (SA); and (3) hydrogen peroxide (H2O2) content. Furthermore, we evaluated the effects of experimentally water-stressed broad-bean plants on N. viridula performance in terms of adult host–plant preference, and nymph growth and survival. Water stress significantly reduced both photosynthesis (A) and stomatal conductance (gs), while infestation by the green stink bug had no effects on photosynthesis but s…