Learn More
The signaling hypothesis of eggshell coloration in birds is based on the assumption that females of species with blue-green eggs signal their phenotypic quality to their mates through deposition of the antioxidant biliverdin as pigment. Egg pigmentation may be an expression of the condition of females at laying or of genetic linkages between egg color and(More)
Multiple invasions (MIs) or infections, i.e. those by more than 1 parasite in the same erythrocyte, could be the result of parasite density or, alternatively, to parasite-related factors or host-related factors. According to the last possibility, to our knowledge, only 3 laboratory studies of malaria have found an increase in the occurrence of MIs when(More)
Multiple infections, those by more than one parasite in the same erythrocyte, may be adaptive for the malarial parasite as a means to ensure fertility. Alternatively they may simply be the consequence of a non-adaptive process forcing several parasites to compete for resources in one host cell. Avian hosts infected with Haemoproteus were medicated with(More)
There is increasing evidence that sexual selection operates in females and not only in males. However, the function of female signals in intrasexual competition has been little studied in species with conventional sex roles. In the Iberian populations of the pied flycatcher (Ficedula hypoleuca), some females express a white forehead patch, a trait that in(More)
While avian chronic haemoparasite infections induce reproductive costs, infection has not previously been shown to affect survival. Here, we experimentally reduced, through medication, the intensity of infection by Haemoproteus parasites in wild-breeding female blue tits Cyanistes caeruleus. However, this treatment did not reduce the intensity of infection(More)
Mechanisms affecting patterns of vector distribution among host individuals may influence the population and evolutionary dynamics of vectors, hosts and the parasites transmitted. We studied the role of different factors affecting the species composition and abundance of Culicoides found in nests of the blue tit (Cyanistes caeruleus). We identified 1531(More)
Compared to non-flying nest-dwelling ectoparasites, the biology of most species of flying ectoparasites and its potential impact on avian hosts is poorly known and rarely, if ever, reported. In this study we explore for the first time the factors that may affect biting midge (Diptera: Ceratopogonidae) and black fly (Diptera: Simuliidae) abundances in the(More)
Some avian species incorporate aromatic plants to their nests. The "nest protection hypothesis", which posits that volatile secondary compounds contained in these plants may have antiparasite properties, has not received full support. All previous tests of this hypothesis have only considered effects on nest-dwelling ectoparasites, but not on blood-sucking(More)
We have aimed at detecting prelaying maternal effects on nestling antibody defences and growth through experimental food supplementation of female pied flycatchers Ficedula hypoleuca and subsequent exchange of whole clutches with control nests. The levels of immunoglobulins and the mass and size of chicks at 12 days of age were ascertained. This is the(More)
We investigated the physiological and behavioral consequences for prey breeding at different distances from a nesting predator. In a natural setting, Pied Flycatchers (Ficedula hypoleuca) made territory location decisions relative to established Sparrowhawk (Accipiter nisus) nests. From female flycatchers attending nests at different distances from(More)