Search results for "Aging"
showing 10 items of 10496 documents
Can video playback provide social information for foraging blue tits?
2017
Video playback is becoming a common method for manipulating social stimuli in experiments. Parid tits are one of the most commonly studied groups of wild birds. However, it is not yet clear if tits respond to video playback or how their behavioural responses should be measured. Behaviours may also differ depending on what they observe demonstrators encountering. Here we present blue tits (Cyanistes caeruleus) videos of demonstrators discovering palatable or aversive prey (injected with bittertasting Bitrex) from coloured feeding cups. First we quantify variation in demonstrators’ responses to the prey items: aversive prey provoked high rates of beak wiping and head shaking. We then show tha…
Leading role of the sea urchin Arbacia lixula in maintaining the barren state in southwestern Mediterranean
2011
Sympatric sea urchin species are usually considered to belong to the same grazer guild. Nevertheless, their role in community dynamics may vary due to species-specific morphological traits, feeding preferences and foraging behavior. In the Mediterranean Sea, the two species Paracentrotus lividus and Arbacia lixula co-occur in barren areas. Whereas P. lividus is usually considered responsible for creating a barren ground, the roles of the two sea urchin species in its maintenance are currently unclear. The relative and combined effects of P. lividus and A. lixula on maintaining the benthic community in the barren state were tested experimentally, using orthogonal exclusion of the two species…
Quantitative Genetics of the Aging of Reproductive Traits in the Houbara Bustard
2015
International audience; Do all traits within an organism age for the same reason? Evolutionary theories of aging share a common assumption: the strength of natural selection declines with age. A corollary is that additive genetic variance should increase with age. However, not all senescent traits display such increases suggesting that other mechanisms may be at play. Using longitudinal data collected from more than 5400 houbara bustards (Chlamydotis undulata) with an exhaustive recorded pedigree, we investigated the genetics of aging in one female reproductive trait (egg production) and three male reproductive traits (courtship display rate, ejaculate size and sperm viability), that displa…
Response to: The metabolic cost of whistling is low but measurable in dolphins
2020
Costs of sound production have been investigated only sparsely in cetaceans, despite recent efforts to understand how increasing anthropogenic noise affects these animals that rely extensively on sound for communication and foraging. Theoretical estimates suggest that metabolic costs of whistling
Non-consumptive effects between predators depend on the foraging mode of intraguild prey.
2020
Predator non-consumptive effects (NCE) are a suite of phenotypic responses of prey to avoid predation that cascade down food webs and can have a stronger impact than predation itself. However, the role of NCE in intraguild interactions remains understudied. Thus, multi-species experiments based on species traits are needed to improve our understanding of the impact of NCE on community structure. We investigated NCE of ants on 17 spider species as intraguild prey (8 cursorial and 9 sedentary) to test the influence of spider hunting mode on the strength of NCE. Sedentary spiders select a habitat patch and wait for prey, whereas cursorial spiders roam around searching for prey. Because activel…
Octopamine increases individual and collective foraging in a neotropical stingless bee
2020
The biogenic amine octopamine (OA) is a key modulator of individual and social behaviours in honeybees, but its role in the other group of highly eusocial bees, the stingless bees, remains largely unknown. In honeybees, OA mediates reward perception and affects a wide range of reward-seeking behaviours. Thus, we tested the hypothesis that OA increases individual foraging effort and collective food source exploitation in the neotropical stingless bee Plebeia droryana . OA treatment caused a significant increase in the number of bees at artificial sucrose feeders and a 1.73-times higher individual foraging frequency. This effect can be explained by OA lowering the sucrose response threshold …
Improving the analysis of biogeochemical patterns associated with internal waves in the strait of Gibraltar using remote sensing images
2018
High Amplitude Internal Waves (HAIWs) are physical processes observed in the Strait of Gibraltar (the narrow channel between the Atlantic Ocean and the Mediterranean Sea). These internal waves are generated over the Camarinal Sill (western side of the strait) during the tidal outflow (toward the Atlantic Ocean) when critical hydraulic conditions are established. HAIWs remain over the sill for up to 4 h until the outflow slackens, being then released (mostly) towards the Mediterranean Sea. These have been previously observed using Synthetic Aperture Radar (SAR), which captures variations in surface water roughness. However, in this work we use high resolution optical remote sensing, with the…
The effect of maze complexity on maze-solving time in a desert ant
2019
One neglected aspect of research on foraging behavior is that of the effect of obstacles that increase habitat complexity on foraging efficiency. Here, we explored how long it takes individually foraging desert ant workers (Cataglyphis niger) to reach a food reward in a maze, and examined whether maze complexity affects maze-solving time (the time elapsed till the first worker reached the food reward). The test mazes differed in their complexity level, or the relative number of correct paths leading to the food reward, vs. wrong paths leading to dead-ends. Maze-solving time steeply increased with maze complexity, but was unaffected by colony size, despite the positive correlation between co…
Testing the habituation assumption underlying models of parasitoid foraging behavior
2016
BackgroundHabituation, a form of non-associative learning, has several well-defined characteristics that apply to a wide range of physiological and behavioral responses in many organisms. In classic patch time allocation models, habituation is considered to be a major mechanistic component of parasitoid behavioral strategies. However, parasitoid behavioral responses to host cues have not previously been tested for the known, specific characteristics of habituation.MethodsIn the laboratory, we tested whether the foraging behavior of the egg parasitoidTrissolcus basalisshows specific characteristics of habituation in response to consecutive encounters with patches of host (Nezara viridula) ch…
The response of an egg parasitoid to substrate-borne semiochemicals is affected by previous experience
2016
AbstractAnimals can adjust their behaviour according to previous experience gained during foraging. In parasitoids, experience plays a key role in host location, a hierarchical process in which air-borne and substrate-borne semiochemicals are used to find hosts. In nature, chemical traces deposited by herbivore hosts when walking on the plant are adsorbed by leaf surfaces and perceived as substrate-borne semiochemicals by parasitoids. Chemical traces left on cabbage leaves by adults of the harlequin bug (Murgantia histrionica) induce an innate arrestment response in the egg parasitoid Trissolcus brochymenae characterized by an intense searching behaviour on host-contaminated areas. Here we …