Search results for "SEL"
showing 10 items of 14031 documents
The probable function of abdominal contractions and liquid drops during the emergence of Zygoptera and Anisoptera (Odonata)
2016
The transition between larval and adult stage in amphibious insects is called emergence. During emergence abdominal contractions and excretion of liquid drops can be observed in several insect orders. Since the function of these processes is not yet known in odonates, this study examines the probable function of abdominal contractions and excretion of liquid drops in Zygoptera and Anisoptera. By subdividing the emergence into 12 successive stages and counting abdominal contractions as well as the excreted liquid drops during these stages we set up a systematic data collection. In all investigated individuals, both processes began in the middle of the entire emergence. We found that abdomina…
The cost-effectiveness of using raptor nest sites to identify areas with high species richness of other taxa
2016
Abstract Given the limited resources available for conservation, it is important that the areas to preserve are selected in a cost effective manner. However, the cost effectiveness of the surrogate species strategy (the use of information on one or more species to identify areas of value for other species for which there is no, or more limited, available information) has seldom been evaluated. In this study, we investigate the opportunity cost of setting aside breeding sites of two forest raptor species (the surrogate species) by evaluating their individual and combined contribution to preserve diversity of polypores (wood-decaying fungi) and birds against the contributions of previously es…
Age, condition and dominance-related sexual ornament size before and during the breeding season in the black grouse Lyrurus tetrix
2018
Male ornaments function as honest cues of male quality in many species and are subject to intra- and intersexual selection. These ornaments are generally studied during peak expression, however their size outside the breeding season may determine ultimate ornament size and costliness, and as such reproductive success. We investigated whether male black grouse Lyrurus tetrix eye comb size was related to age, condition and measures of male dominance before and during the breeding season. Total combined eye comb size began to increase ~70 d before the start of the breeding season. Adult males (aged ≥ 2 yr old) had consistently larger eye combs than younger males (1 yr old) both before and duri…
Modelling binary mixtures of herbicides in populations resistant to one of the components: evaluation for resistance management
2008
BACKGROUND: Herbicide mixtures are commonly proposed to delay the selection of herbicide resistance in susceptible populations (called the SM strategy). However, in practice, herbicide mixtures are often used when resistance to one of the two active ingredients has already been detected in the targeted population (called the RM strategy). It is doubtful whether such a practice can select against resistance, as the corresponding selection pressure is still exerted. As a consequence, the effect of mixtures on the evolution of an already detected resistance to one of the herbicides in the combination remains largely unexplored. In the present work, a simple model was developed to explore furth…
The mechanistic basis of demographic Allee effects: The search for mates
2017
In Focus: Berec, L., Kremer, A.M., Bernhauverova, V., & Drake, J.M. (2017). Density-dependent selection on mate-finding Allee effects. Journal of Animal Ecology, 87, 24-35. https://doi.org/10.1111/1365-2656.12662 In Focus: Shaw, A.K., Kokko, H., & Neubert, M.G. (2017). Details of mate finding drive dynamics of sex structured invasions. Journal of Animal Ecology, 87, 36-46. https://doi.org/10.1111/1365-2656.12658 Lowered population growth ability at low abundances is called the demographic Allee effect. The difficulty of finding mates in a sparse population is the best documented pathway through which a demographic Allee effect might arise. The articles in focus here aim to establish the mec…
Individual level consistency and correlations of fish spatial behaviour assessed from aquatic animal telemetry
2017
The potential for populations to undergo adaptive evolution depends on individual variation in traits under selection and how multiple traits are correlated. While fitness relates to the performance of animals in the wild, most of the research on evolutionary potential of behavioural traits has used captive or mesocosm settings, especially with aquatic organisms. We investigated the individual level consistency (personalities) and correlations (behavioural syndromes) of fitness-related behavioural traits displayed by a harvested marine fish in the natural environment, and the potential of such individual level behaviour to constrain adaptive evolution. For this, we acoustically tracked 303 …
Density dependence of infanticide and recognition of pup sex in male bank voles
2010
[Infanticide — the killing of conspecific young — is a common phenomenon in many invertebrate and vertebrate species, particularly common in rodents. It can increase juvenile mortality and, thus, affect population growth. Male infanticide is explained by adaptive hypotheses based on sexual selection. Removing future competitors for mating opportunities would require recognition of pup sex and directing infanticide against male pups. We studied whether the sex of a pup and population density affect male bank voles' ( Myodes glareolus ) aggressive behaviour towards conspecific pups. Population density increased aggressiveness. Against our predictions, male bank voles from high density populat…
An electrochemical analysis suggests role of gynodioecy in adaptation to stress in Cortaderia selloana
2018
Cortaderia selloana is an invasive, gynodioecious species prevalent in Mediterranean area which contains both female and hermaphrodite specimens in the wild population. Using voltammetric data we show that the female and hermaphrodite specimens exhibit differential electrochemical response. Cortaderia selloana leaves from two different provenances in the Valencia Mediterranean area, Sueca and Cullera (Comunitat Valenciana, Spain), in the surroundings of the Albufera Natural Park, a peculiar ecosystem containing unspoilt dune beaches and forests, were studied to determine correlation of flower morphology with the plant's ability to adapt to stress conditions. Our data suggests that gynodioec…
Harvesting changes mating behaviour in European lobster
2018
Removing individuals from a wild population can affect the availability of prospective mates and the outcome of competitive interactions, with subsequent effects on mating patterns and sexual selection. Consequently, the rate of harvest‐induced evolution is predicted to be strongly dependent on the strength and dynamics of sexual selection, yet there is limited empirical knowledge on the interplay between selective harvesting and the mating systems of exploited species. In this study, we used genetic parentage assignment to compare mating patterns of the highly valued and overexploited European lobster (Homarus gammarus) in a designated lobster reserve and nearby fished area in southern Nor…
Exploring individual and population eco-evolutionary feedbacks under the coupled effects of fishing and predation
2020
Intensive fishing that selects for large and old individuals can have pervasive effects on traits directly associated with the fecundity and survival of the target species. The observed reduction in fish body size can result in earlier sexual maturity at a smaller body size, leading to a lower individual reproductive output and population productivity in the long term. In addition, increased predation can induce similar responses in age and size at maturity due to the release of intraspecific competition and the lower population density. Thus, the combined impact of fisheries and predation is more difficult to predict due to their competition for fish, ultimately limiting and directing the …