Search results for "GRI"

Eco‐evolutionary dynamics driven by fishing : from single species models to dynamic evolution within complex food webs

2020

Evidence of contemporary evolution across ecological time scales stimulated research on the eco‐evolutionary dynamics of natural populations. Aquatic systems provide a good setting to study eco‐evolutionary dynamics owing to a wealth of long‐term monitoring data and the detected trends in fish life‐history traits across intensively harvested marine and freshwater systems. In the present study, we focus on modelling approaches to simulate eco‐evolutionary dynamics of fishes and their ecosystems. Firstly, we review the development of modelling from single‐species to multispecies approaches. Secondly, we advance the current state‐of‐the‐art methodology by implementing evolution of life‐history…

Variation in the COI gene of the freshwater pearl mussel Margaritifera margaritifera from River Vuokkijoki

2017

The freshwater pearl mussel Margaritifera margaritifera L. is one of the most endangered freshwater mussels in the world. Effective conservation of threatened species requires not only ecological, but also genetic information from the target species and populations. Since low genetic diversity can reduce the ability of a species to adapt to environmental changes, maintaining genetic diversity has been identified as one of the key elements in successful conservation programs. We examined genetic variation of the freshwater pearl mussel from the River Vuokkijoki, Karelia, Russia. We sequenced a fragment of the cytochrome c oxidase subunit I gene (COI) from 22 individuals and compared the data…

Evaluating responses to temperature during pre-metamorphosis and carry-over effects at post-metamorphosis in the wood tiger moth (Arctia plantaginis)

2019

Insect metamorphosis is one of the most recognized processes delimiting transitions between phenotypes. It has been traditionally postulated as an adaptive process decoupling traits between life stages, allowing evolutionary independence of pre- and post-metamorphic phenotypes. However, the degree of autonomy between these life stages varies depending on the species and has not been studied in detail over multiple traits simultaneously. Here, we reared full-sib larvae of the warningly coloured wood tiger moth ( Arctia plantaginis ) in different temperatures and examined their responses for phenotypic (melanization change, number of moults), gene expression (RNA-seq and qPCR of candidate ge…

Broad thermal tolerance is negatively correlated with virulence in an opportunistic bacterial pathogen

2018

Predicting the effects of global increase in temperatures on disease virulence is challenging, especially for environmental opportunistic bacteria, because pathogen fitness may be differentially affected by temperature within and outside host environment. So far, there is very little empirical evidence on the connections between optimal temperature range and virulence in environmentally growing pathogens. Here, we explored whether the virulence of an environmentally growing opportunistic fish pathogen, Flavobacterium columnare, is malleable to evolutionary changes via correlated selection on thermal tolerance. To this end, we experimentally quantified the thermal performance curves (TPCs) f…

2018

BackgroundThe insect cuticle covers the whole body and all appendages and has bi-directionnal selective permeability: it protects against environmental stress and pathogen infection and also helps to reduce water loss. The adult cuticle is often associated with a superficial layer of fatty acid-derived molecules such as waxes and long chain hydrocarbons that prevent rapid dehydration. The waterproofing properties of cuticular hydrocarbons (CHs) depend on their chain length and desaturation number.DrosophilaCH biosynthesis involves an enzymatic pathway including several elongase and desaturase enzymes.MethodsThe link between desiccation resistance and CH profile remains unclear, so we tested…

Foraging behaviour of an egg parasitoid exploiting plant volatiles induced by pentatomids : The role of adaxial and abaxial leaf surfaces

2017

Several phases of herbivorous insect attack including feeding and oviposition are known to induce plant defenses. Plants emit volatiles induced by herbivores to recruit insect parasitoids as an indirect defense strategy. So far, volatiles induced by herbivore walking and their putative role in the foraging behavior of egg parasitoids have not been investigated. In this paper we studied the response of the egg parasitoid Trissolcus basalis toward volatiles emitted by Vicia faba plants as consequence of the walking activity of the host Nezara viridula. Olfactometer bioassays were carried out to evaluate wasp responses to plants in which the abaxial or the adaxial surfaces were subjected to wa…

Implications of size‐selective fisheries on sexual selection

2019

Fisheries often combine high mortality with intensive size‐selectivity and can, thus, be expected to reduce body size and size variability in exploited populations. In many fish species, body size is a sexually selected trait and plays an important role in mate choice and mate competition. Large individuals are often preferred as mates due to the high fecundity and resources they can provide to developing offspring. Large fish are also successful in competition for mates. Fisheries‐induced reductions in size and size variability can potentially disrupt mating systems and lower average reproductive success by decreasing opportunities for sexual selection. By reducing population sizes, fisher…

The current and future state of animal coloration research

2017

Animal colour patterns are a model system for understanding evolution because they are unusually accessible for study and experimental manipulation. This is possible because their functions are readily identifiable. In this final paper of the symposium we provide a diagram of the processes affecting colour patterns and use this to summarize their functions and put the other papers in a broad context. This allows us to identify significant ‘holes’ in the field that only become obvious when we see the processes affecting colour patterns, and their interactions, as a whole. We make suggestions about new directions of research that will enhance our understanding of both the evolution of colour …

Ants medicate to fight disease

2015

Parasites are ubiquitous, and the ability to defend against these is of paramount importance. One way to fight diseases is self-medication, which occurs when an organism consumes biologically active compounds to clear, inhibit, or alleviate disease symptoms. Here, we show for the first time that ants selectively consume harmful substances (reactive oxygen species, ROS) upon exposure to a fungal pathogen, yet avoid these in the absence of infection. This increased intake of ROS, while harmful to healthy ants, leads to higher survival of exposed ants. The fact that ingestion of this substance carries a fitness cost in the absence of pathogens rules out compensatory diet choice as the mechanis…

Acclimation capacity and rate change through life in the zooplankton Daphnia

2020

When a change in the environment occurs, organisms can maintain an optimal phenotypic state via plastic, reversible changes to their phenotypes. These adjustments, when occurring within a generation, are described as the process of acclimation. While acclimation has been studied for more than half a century, global environmental change has stimulated renewed interest in quantifying variation in the rate and capacity with which this process occurs, particularly among ectothermic organisms. Yet, despite the likely ecological importance of acclimation capacity and rate, how these traits change throughout life among members of the same species is largely unstudied. Here we investigate these re…