Search results for "time allocation"
showing 10 items of 11 documents
Nest guarding behaviour of a temperate wrasse differs between sites off Mediterranean CO2 seeps
2021
Abstract Organisms may respond to changing environmental conditions by adjusting their behaviour (i.e., behavioural plasticity). Ocean acidification (OA), resulting from anthropogenic emissions of carbon dioxide (CO2), is predicted to impair sensory function and behaviour of fish. However, reproductive behaviours, and parental care in particular, and their role in mediating responses to OA are presently overlooked. Here, we assessed whether the nesting male ocellated wrasse Symphodus ocellatus from sites with different CO2 concentrations showed different behaviours during their breeding season. We also investigated potential re-allocation of the time-budget towards different behavioural act…
Genetic variation in the mechanisms of direct mutual interference in a parasitic wasp: consequences in terms of patch-time allocation
2004
Summary 1. Direct mutual interference between insect parasitoids has always been considered to have major consequences for the population dynamics of parasitoid‐host systems. Furthermore, patch time allocation has also always been presented as an important behavioural component that is closely involved in the demographic features of host‐ parasitoid interactions. 2. Based on a detailed analysis of within-patch interactions between Trissolcus basalis (Hymenoptera: Scelionidae) females, the present study aimed to understand accurately how direct mutual interference can influence patch time allocation in this species. 3. The genetic variation in the behavioural mechanisms involved in the inter…
Variation in predation risk and vole feeding behaviour: a field test of the risk allocation hypothesis.
2003
Many prey animals experience temporal variation in the risk of predation and therefore face the problem of allocating their time between antipredator efforts and other activities like feeding and breeding. We investigated time allocation of prey animals that balanced predation risk and feeding opportunities. The predation risk allocation hypothesis predicts that animals should forage more in low- than in high-risk situations and that this difference should increase with an increasing attack ratio (i.e. difference between low- and high-risk situations) and proportion of time spent at high risk. To test these predictions we conducted a field test using bank voles ( Clethrionomys glareolus) as…
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…
Habitat assessment by parasitoids: consequences for population distribution
2006
International audience; The ideal free distribution (IFD) is a stable distribution of competitors among resource patches. For equally efficient competitors, equilibrium is reached when the per capita rate of intake equalizes across patches. The seminal version of the IFD assumes omniscience, but populations may still converge toward the equilibrium provided that competitors 1) accurately assess their environment by learning and 2) remain for an optimal (rate-maximizing) time on each encountered patch. In the companion article (Tentelier C, Desouhant E, Fauvergue X. 2006. Habitat assessment by parasitoids: mechanisms for patch time allocation. Behav Ecol. Forthcoming), it is shown that the p…
Time allocation during Higher education : a study of Brazilian, French and Spanish students
1995
International audience; The results we present enable us to highlight common features and disparities in the way students from the three countries organize their time. While the lecture attendance time varies little from one country to another, it is different for other elements of time use. The Spaniards in particular seem to spend more time on personal work and the Brazilians more often have paid employment. The initial comparison should however be regarded as provisional in that no systematic correlation was made with educational policies in each country. Certainly, the lack of grants system in Brazil is linked to the significant amount of available time spent on salaried work but it wou…
Thermal stress affects patch time allocation by preventing forgetting in a parasitoid wasp
2015
Learning and memory allow animals to adjust their foraging strategies through experience. Despite the known impact of temperature on many aspects of the behavioral ecology of animals, memory retention in the face of realistic thermal stress has seldom been assessed. In the laboratory, we studied the behavioral expression of an egg parasitoid’s (Trissolcus basalis) memory when exposed to thermal stress that could be encountered in nature. We hypothesized that thermal stress would disrupt memory consolidation and/ or modify the optimality of memory retention, thus affecting patch time allocation strategies. Memory consolidation was resilient to 1 h of thermal stress following an unrewarded ex…
Distributed Resource Allocation for Energy Efficiency in OFDMA Multicell Networks with Wireless Power Transfer
2019
In this paper, an energy-efficient resource allocation problem is investigated for the wireless power transfer (WPT)-enabled OFDMA multicell networks. In the considered system, multiple base stations (BSs) with a large number of antennas are responsible to provide WPT in the downlink, and the users can recycle and utilize the received energy for uplink data transmission. The role of BS is to execute WPT; thus, there are no data transmissions in the downlink. A time-division protocol is considered to divide the time of downlink WPT and uplink wireless information transfer into separate time slots. With the objective to improve the energy efficiency, we propose the time, subcarrier, and power…
Energy efficient and distributed resource allocation for wireless powered OFDMA multi-cell networks
2017
In this paper, we investigate the energy efficient resource allocation problem for the wireless powered OFDMA multi-cell networks. In the considered system, the users who have data to transmit in the uplink can only be empowered by the wireless power obtained from multiple base stations (BSs) with a large scale of multiple antennas in the downlink. A time division protocol is considered to divide the time of wireless power transfer (WPT) in the downlink and wireless information transfer (WIT) in the uplink into separate time slot. With the objective to improve the energy efficiency (EE) of the system, we propose the antenna selection, time allocation, subcarrier and power allocation schemes…
The disenchantment of professionals in a new, implemented model of primary health care in Spain: A structural equations model
1992
Abstract A new model of primary health care has been progressively implemented in Spain. Previous research (Peiro and Gonzalez-Roma 1991) suggested that the implementation of this new model has produced a kind of disenchantment—that is, an experience of negative surprise—among health care professionals involved. In the present paper, a structural equations model about the antecedents and consequences of the experience of surprise is tested in a sample of 432 health care professionals working in 44 Primary Health Care Teams (PHCT). The results obtained showed that the number of uncovered functions in the PHCTs, the discrepancy between actual and desired time allocation, and the assessment of…