Search results for " research"
showing 10 items of 14115 documents
Predators' consumption of unpalatable prey does not vary as a function of bitter taste perception
2020
Many prey species contain defensive chemicals that are described as tasting bitter. Bitter taste perception is, therefore, assumed to be important when predators are learning about prey defenses. However, it is not known how individuals differ in their response to bitter taste, and how this influences their foraging decisions. We conducted taste perception assays in which wild-caught great tits (Parus major) were given water with increasing concentrations of bitter-tasting chloroquine diphosphate until they showed an aversive response to bitter taste. This response threshold was found to vary considerably among individuals, ranging from chloroquine concentrations of 0.01 mmol/L to 8 mmol/L.…
Mediterranean identities - environment, society, culture
2017
The Mediterranean Sea, one of the most complex marine ecosystems, is inhabited by a rich and diverse biota which is disproportionate to its dimensions. It is cur‐ rently affected by different pressures, mainly driven by human activities such as cli‐ mate change and bioinvasions. This Sea, also due to its geographic position (wedged between the temperate climate of central Europe and the arid climate of northern Africa), seems to be one of the regions most susceptible to global climate change. The increased rates of introduction and spread of marine alien species may represent a supplementary stress factor to Mediterranean marine native biota already challenged by climatic abnormalities. The…
Ecological response hides behind the species abundance distribution : Community response to low-intensity disturbance in managed grasslands
2017
Land-use and management are disturbance factors that have diverse effects on community composition and structure. In traditional rural grasslands, such as meadows and pastures, low-intensity management is maintained to enhance biodiversity. Maintenance of road verges, in turn, creates habitat, which may complement traditional rural grasslands. To evaluate the effect of low-intensity disturbance on insect communities, we characterized species abundance distributions (SAD) for Carabidae, Formicidae, and Heteroptera in three grassland types, which differed in management: meadows, pastures, and road verges. The shape of SAD was estimated with three parameters: abundance decay rate, dominance, a…
Light availability and land‐use history drive biodiversity and functional changes in forest herb layer communities
2020
International audience; A central challenge of today's ecological research is predicting how ecosystems will develop under future global change. Accurate predictions are complicated by (a) simultaneous effects of different drivers, such as climate change, nitrogen deposition and management changes; and (b) legacy effects from previous land use. We tested whether herb layer biodiversity (i.e. richness, Shannon diversity and evenness) and functional (i.e. herb cover, specific leaf area [SLA] and plant height) responses to environmental change drivers depended on land-use history. We used resurvey data from 192 plots across nineteen European temperate forest regions, with large spatial variabi…
Reproductive timing and individual fitness
2002
Estimation of individual fitness – i.e. description of the extent to which an individual's genes are represented in future generations – is a feature central to most evolutionary studies. Lifetime reproductive success (LRS) is a commonly used estimate of individual fitness, but because it is rate-insensitive (i.e. timing of reproductive events is not incorporated), it may give a biased estimate of fitness when reproductive timing is an important component of fitness. A review of all empirical studies which have used a recently derived, rate-sensitive estimate of individual fitness, λind revealed that λind ranks the fitness of phenotypes differently from LRS, and that this difference may lea…
Gray plumage color is more cryptic than brown in snowy landscapes in a resident color polymorphic bird
2020
Abstract Camouflage may promote fitness of given phenotypes in different environments. The tawny owl (Strix aluco) is a color polymorphic species with a gray and brown morph resident in the Western Palearctic. A strong selection pressure against the brown morph during snowy and cold winters has been documented earlier, but the selection mechanisms remain unresolved. Here, we hypothesize that selection favors the gray morph because it is better camouflaged against predators and mobbers in snowy conditions compared to the brown one. We conducted an online citizen science experiment where volunteers were asked to locate a gray or a brown tawny owl specimen from pictures taken in snowy and snow…
An Updated Checklist of the Sicilian Native Edible Plants: Preserving the Traditional Ecological Knowledge of Century-Old Agro-Pastoral Landscapes
2020
The traditional use of native wild food plants (NWFP) may represent a valuable supplementary food source for the present and future generations. In Sicily, the use of wild plants in the human diet dates back to very ancient times and still plays an important role in some rural communities. Moreover, in this regard, the natural and cultural inheritance of this island is wealthy and diversified for several reasons. First, Sicily hosts a rich vascular flora, with 3,000 native and 350 endemic plants. Second, due to its central position in the Mediterranean, the island has acted as a veritable melting pot for the ethnobotanical knowledge of the rural communities of the entire basin. We reviewed …
Hyperparasitoids exploit herbivore-induced plant volatiles during host location to assess host quality and non-host identity
2019
Although consumers often rely on chemical information to optimize their foraging strategies, it is poorly understood how top carnivores above the third trophic level find resources in heterogeneous environments. Hyperparasitoids are a common group of organisms in the fourth trophic level that lay their eggs in or on the body of other parasitoid hosts. Such top carnivores use herbivore-induced plant volatiles (HIPVs) to find caterpillars containing parasitoid host larvae. Hyperparasitoids forage in complex environments where hosts of different quality may be present alongside non-host parasitoid species, each of which can develop in multiple herbivore species. Because both the identity of th…
Whistle variation in Mediterranean common bottlenose dolphin: The role of geographical, anthropogenic, social, and behavioral factors.
2020
Abstract The studies on the variation of acoustic communication in different species have provided insight that genetics, geographic isolation, and adaptation to ecological and social conditions play important roles in the variability of acoustic signals. The dolphin whistles are communication signals that can vary significantly among and within populations. Although it is known that they are influenced by different environmental and social variables, the factors influencing the variation between populations have received scant attention. In the present study, we investigated the factors associated with the acoustic variability in the whistles of common bottlenose dolphin (Tursiops truncatu…
Value of information in multiple criteria decision making: an application to forest conservation
2019
Abstract Developing environmental conservation plans involves assessing trade-offs between the benefits and costs of conservation. The benefits of conservation can be established with ecological inventories or estimated based on previously collected information. Conducting ecological inventories can be costly, and the additional information may not justify these costs. To clarify the value of these inventories, we investigate the multiple criteria value of information associated with the acquisition of improved ecological data. This information can be useful when informing the decision maker to acquire better information. We extend the concept of the value of information to a multiple crite…