Search results for "competition"
showing 10 items of 1409 documents
Commitment and choice of partner in a negotiation with a deadline
2002
This paper analyses the effects of partially revocable endogenous commitments of a seller in a negotiation with a deadline. In particular, we examine when commitment is a source of strength, a source of inefficiency and when it does not affect the bargaining outcome at all. We show that when commitment possesses a minimum amount of irrevocability this crucially determines the bargaining outcome. In the bilateral bargaining case, commitment becomes a source of inefficiency since it causes a deadline effect. In the choice of partner framework, however, the deadline effect disappears and there is an immediate agreement and, moreover, commitment becomes a source of strength since it increases t…
RESEARCH PAPER: Multiple Sexual Ornamentation Signals Male Quality and Predicts Female Preference in Minnows
2010
Sexual ornamentation often consists of multiple components. Different sexual signals may indicate different aspects of mate quality or reflect quality in different time scales. On the other hand, same signals can have a dual function and are used both in male–male competition and courtship. Many fish species are capable of rapidly altering their colouration (ephemeral colour changes), but this capability is usually ignored in sexual selection studies. Here, we used experimentally manipulated social environments to study the ephemeral colour changes in multicomponent sexual signals of male minnows (Phoxinus phoxinus) during male–male competition and female choice. We found that the dominant …
Intraguild interactions between egg parasitoids: window of opportunity and fitness costs for a facultative hyperparasitoid.
2013
We investigated intraguild interactions between two egg parasitoids of Nezara viridula (L.) (Heteroptera: Pentatomidae), Ooencyrtus telenomicida (Vassiliev) (Hymenoptera: Encyrtidae) and Trissolcus basalis (Wollaston) (Hymenoptera: Platygastridae), as the former has the potential to be a facultative hyperparasitoid of the latter. We assessed the suitability of N. viridula eggs for the development of O. telenomicida as a function of egg age when they were unparasitized, or had been attacked by T. basalis at different times prior to exposure to O. telenomicida females. Ooencyrtus telenomicida can exploit healthy N. viridula host eggs up to 5 days of age, just prior to the emergence of N. viri…
Intestinal distribution and fecundity of two species ofDiplostomumparasites in definitive hosts
2005
This paper investigated the intestinal distribution and fecundity of 2 species ofDiplostomumparasites,D. spathaceumandD. pseudospathaceum, in 2 species of definitive hosts, herring gull (Larus argentatus) and common gull (L. canus), using both empirical field data and experimental infections. At the level of individual hosts, the parasite species occupied different parts within the intestine, but the fecundity of the worms, measured as the number of eggs in the uterus, did not differ between the parasite species except in wild common gulls. Interestingly, egg numbers in individual hosts were positively correlated between the parasite species suggesting that some birds provided better resour…
Intraguild interactions between two egg parasitoids of a true bug in semi-field and field conditions.
2014
International audience; Research on interspecific competitive interactions among insect parasitoids has often been characterized by laboratory studies in which host insects are exposed to female parasitoids of different species in various sequences and combinations. In the last years, an increasing number of studies have investigated interspecific interactions under field and semi-field conditions although just a few number of works focused on egg parasitoids. In this work, we undertook a two-year study to investigate interspecific interactions between Trissolcus basalis (Wollaston) (Hymenoptera: Platygastridae) and Ooencyrtus telenomicida (Vassiliev) (Hymenoptera: Encyrtidae), two egg para…
“Red wins”, “black wins” and “blue loses” effects are in the eye of beholder, but they are culturally universal: A cross-cultural analysis of the inf…
2014
Abstract Although many studies have demonstrated an influence of uniform colors on sports performance, there are still more questions than answers regarding this issue. In our study, participants from Poland (N = 147) and China (N = 143) watched a two-minute video of a semi-professional boxing match. The participants viewed six different versions of the same fight - the original was modified to change the colors of the boxers’ trunks (red vs. blue, blue vs. red, blue vs. black, black vs. blue, red vs. black, and black vs. red). We experimentally confirmed that “black wins” and “red wins” effects exist, but in a way that caused an erroneous perception of the number of blows landed by boxers …
Care Poverty Within the Home Space: Exploring the Emotional Experiences of Unmet Care Needs
2021
Older adults face inequalities in care. The concept of care poverty has been developed to point out how unmet care needs are not just an individual issue but a phenomenon linked to social and economic disadvantage and societal inequality. In this paper, we approach the question of care poverty by focusing on its intertwinement with emotions and the home space. We analyze how the presence, or more commonly absence, of care shapes interviewees’ descriptions of emotional experiences tied to the home space. Our data consists of 12 semi-structured interviews conducted in 2019 and 2020 with customers of outreach work for older adults in Finland. These customers typically face a situation that can…
The leisure construction in adolescents and this influence for development of criminal careers
2013
La construcción de actividades de ocio incide directamente en el desarrollo evolutivo de los adolescentes, capacitándolos para una sana socialización en sus espacios cotidianos. La complejidad que plantea el diseño de actividades y programas de ocio requiere el esfuerzo común de los diferentes agentes; así, tanto las administraciones públicas, como los padres, profesionales, los propios adolescentes y las entidades gestoras de estos programas han de coordinar sus esfuerzos en pro de desarrollar equilibradamente los espacios con las propuestas para el ocio. De estas actividades, las encaminadas hacia el recreo supervisado permiten crecer en positivo, pero la alarma aparece cuando los espacio…
Data from: Experimental contact zones reveal causes and targets of sexual selection in hybridizing lizards
2017
Divergence in sexually selected traits in allopatry should affect the degree and direction of hybridization. However, few studies have established the causes and targets of sexual selection during secondary contact. Common wall lizards (Podarcis muralis) from north-central Italy have highly exaggerated male sexual traits compared to populations in Western Europe. Using experimental populations, we show that this creates asymmetries in male dominance, spatial habitat use and reproductive success upon secondary contact. Hybridization occurred almost exclusively between males of the Italian lineage and females of the Western European lineage. We provide evidence to suggest stronger ongoing sel…
Data from: When earwig mothers do not care to share: parent-offspring competition and the evolution of family life
2018
1. Kin competition often reduces – and sometimes entirely negates – the benefits of cooperation among relatives, and hence is often regarded as central process in social evolution. Surprisingly, however, our understanding of the role of kin competition in the evolution of family life remains fragmentary, despite the close scrutiny it received in studies on sibling rivarly. This is because much less attention has been given to local competition between parents and their offspring, and its potential impact on the early evolution of parental care and family life. 2. Here, we examined mother-offspring competition over food access in the European earwig Forficula auricularia, an insect with facu…