Search results for "Brood parasite"

The evolution of parental care in insects: the roles of ecology, life history and the social environment

2013

Parental care increases the fitness of offspring at a cost to the parents in terms of residual reproductive success. This trade-off may be affected by ecology, life history and the social environment, which raises the question as to how these factors contribute to the evolution of parental care. Here, previous hypotheses concerning the evolution of parental care in insects are summarized and discussed and the underlying empirical evidence is reviewed. Ecological factors such as harsh environments, ephemeral food sources or predation pressure are broadly accepted as evolutionary drivers of parental care. The most consistent evidence supports a role for natural enemies such as predators, micr…

Avian brood parasitism in a Mediterranean region. hosts and habitat preferences of Common Cuckoos Cuculus canorus

2009

Capsule Cuckoos in Italy support the ‘host preference’ hypothesis. Aims To identify the species parasitized in a Mediterranean area, in Italy; to quantify the frequency of parasitism on each host species; and to determine whether some species and/or habitat types are parasitized more than expected from a homogeneous distribution. Methods Nest records dating from 1865 were compiled from literature, nest card programmes, and personal communication with ornithologists working in the region. Comparisons of parasitism frequencies were made among and within habitats for all cuckoo hosts. Results The most frequently parasitized hosts were Great Reed Warbler, European Robin, Marsh Warbler, Redstart…

Use of social over personal information enhances nest defense against avian brood parasitism

2011

Interactions with conspecifics influence the behavioral repertoire of an organism, as they apply to foraging techniques, song acquisition, habitat selection, and mate choice. Few workers have studied the role of social interactions in molding defense responses, especially the defense of the nest. We tested the effect of social interaction on nest defense of the reed warbler (Acrocephalus scirpaceus), one of the main hosts of the brood-parasitic common cuckoo (Cuculus canorus) in Europe. This parasite reduces its host’s breeding success; therefore, any response that prevents successful parasitism should be selected. Because of their high nesting density and consistent cuckoo-specific respons…

Collective defence portfolios of ant hosts shift with social parasite pressure

2014

Host defences become increasingly costly as parasites breach successive lines of defence. Because selection favours hosts that successfully resist parasitism at the lowest possible cost, escalating coevolutionary arms races are likely to drive host defence portfolios towards ever more expensive strategies. We investigated the interplay between host defence portfolios and social parasite pressure by comparing 17 populations of two Temnothorax ant species. When successful, collective aggression not only prevents parasitation but also spares host colonies the cost of searching for and moving to a new nest site. However, once parasites breach the host's nest defence, host colonies should resor…

2021

Because of its parasitic habits, reproduction costs of the common cuckoo (Cuculus canorus) are mostly spent in pre-laying activities. Female costs are limited to searching host nests and laying eggs, whereas, males spend time in performing intense vocal displays, possibly with territorial purpose. This last aspect, together with a sexual plumage dimorphism, points to both intra- and inter-sexual selections operating within this species. One element triggering sexual selection is a differential fitness accrued by different phenotypes. Before analyzing possible sexual selection mechanisms operating in cuckoos, it is therefore necessary to verify whether there is a variability among male secon…

Data from: Collective defence portfolios of ant hosts shift with social parasite pressure

2014

Host defences become increasingly costly as parasites breach successive lines of defence. Because selection favours hosts that successfully resist parasitism at the lowest possible cost, escalating coevolutionary arms races are likely to drive host defence portfolios towards ever more expensive strategies. We investigated the interplay between host defence portfolios and social parasite pressure by comparing 17 populations of two Temnothorax ant species. When successful, collective aggression not only prevents parasitation but also spares host colonies the cost of searching for and moving to a new nest site. However, once parasites breach the host's nest defence, host colonies should resort…