Search results for "Passeriformes"
showing 10 items of 43 documents
Social transmission in the wild can reduce predation pressure on novel prey signals
2021
Funder: Suomen Kulttuurirahasto (Finnish Cultural Foundation); doi: https://doi.org/10.13039/501100003125
GENETIC AND ENVIRONMENTAL VARIATION IN ANTIBODY AND T-CELL MEDIATED RESPONSES IN THE GREAT TIT
2006
Host parasite coevolution assumes pathogen specific genetic variation in host immune defense. Also, if immune function plays a role in the evolution of life history, allocation to immune function should be heritable. We conducted a cross-fostering experiment to test the relative importance of genetic and environmental sources of variation in T-cell mediated inflammatory response and antigen specific antibody responses in the great tits Parus major. Cell mediated response was measured during the nestling period and antibody response against two novel antigens was measured in two-month-old juveniles raised in a laboratory. We found no effect of nest of origin, but a strong effect of rearing e…
The use of blue tit eggs as a biomonitoring tool for organohalogenated pollutants in the European environment
2010
In the present study, large scale geographical variation in the occurrence of organohalogenated pollutants (OHPs) was investigated throughout Europe using eggs of a terrestrial resident passerine species, the blue tit (Cyanistes caeruleus). Blue tit eggs from 10 sampling locations, involving suburban, rural and remote areas, in 7 European countries were collected and analysed. Sum polychlorinated biphenyl (PCB) levels ranged from 150 ng/g lipid weight (lw) to 2003 ng/g lw. Sum polybrominated diphenyl ethers (PBDEs) ranged from 3.95 ng/g lw to 114 ng/g lw. As expected, PCB and PBDE concentrations were significantly higher in the sampled suburban locations compared to the rural and remote loc…
Effects of migratory status and habitat on the prevalence and intensity of infection by haemoparasites in passerines in eastern Spain
2013
Efectos del estatus migratorio y del tipo de habitat sobre la prevalencia y la intensidad de la infeccion por hemoparasitos en paseriformes en el este de Espana La peninsula iberica es un sitio idoneo para estudiar los efectos de la condicion migratoria en la prevalencia de hemoparasitos en comunidades de aves, dado que convergen poblaciones residentes locales con especies migratorias y abundantes poblaciones de vectores. En este trabajo examinamos la incidencia de hemoparasitos presentes en aves de tres localidades de la region mediterranea (este de Espana), con respecto del estatus migratorio. Examinamos 333 frotis sanguineos de 11 especies, y encontramos una prevalencia global del 9,6%. …
Brominated flame retardants and organochlorines in the European environment using great tit eggs as a biomonitoring tool
2009
Large-scale studies are essential to assess the emission patterns and spatial distribution of organohalogenated pollutants (OHPs) in the environment. Bird eggs have several advantages compared to other environmental media which have previously been used to map the distribution of OHPs. In this study, large-scale geographical variation in the occurrence of OHPs, such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and organochlorine pesticides (OCPs), was investigated throughout Europe using eggs of a terrestrial residential passerine species, the great tit (Parus major). Great tit eggs from 22 sampling sites, involving urban, rural and remote areas, in 14 Europea…
Carry-over effects of conditions at the wintering grounds on breeding plumage signals in a migratory bird : roles of phenotypic plasticity and select…
2016
To understand the consequences of ever-changing environment on the dynamics of phenotypic traits, distinguishing between selection processes and individual plasticity is crucial. We examined individual consistency/plasticity in several male secondary sexual traits expressed during the breeding season (white wing and forehead patch size, UV reflectance of white wing patch and dorsal melanin coloration) in a migratory pied flycatcher (Ficedula hypoleuca) population over an 11-year period. Furthermore, we studied carry-over effects of three environmental variables (NAO, a climatic index; NDVI, a vegetation index; and rainfall) at the wintering grounds (during prebreeding moult) on the expressi…
Testosterone and oxidative stress: the oxidation handicap hypothesis
2007
Secondary sexual traits (SST) are usually thought to have evolved as honest signals of individual quality during mate choice. Honesty of SST is guaranteed by the cost of producing/maintaining them. In males, the expression of many SST is testosterone-dependent. The immunocompetence handicap hypothesis has been proposed as a possible mechanism ensuring honesty of SST on the basis that testosterone, in addition to its effect on sexual signals, also has an immunosuppressive effect. The immunocompetence handicap hypothesis has received mixed support. However, the cost of testosterone-based signalling is not limited to immunosuppression and might involve other physiological functions such as the…
Sex-specific differences in offspring personalities across the laying order in magpies Pica pica
2013
Maternal effects provide an important mechanism for mothers to create variation in offspring personality, and to potentially influence offspring life history strategies e.g. creating more/less dispersive phenotypes. However, within-clutch maternal effects often vary and hence there is potential for within-clutch variation in personality. We studied the effects of hatching order on explorative and neophobic behaviour of the magpies Pica pica in relation to sex using novel environment and novel object experiments. Hatching order did affect explorative behaviour in magpie, but did so in opposite directions for either sex. First-hatched females were more explorative and had a tendency to be les…
Translocation as a novel approach to study effects of a new breeding habitat on reproductive output in wild birds
2011
Environmental conditions under which species reproduce have major consequences on breeding success and subsequent fitness. Therefore breeding habitat choice is ultimately important. Studies rarely address the potential fitness pay-offs of alternative natural breeding habitats by experimental translocation. Here we present a new tool to study fitness consequences of free living birds in different habitats. We translocated a migratory passerine, the pied flycatcher (Ficedula hypoleuca), to a novel site, where pairs were subjected to a short stay (2-4 days) in a nest box-equipped aviary before being released. We show that it is technically possible to retain birds in the new area for breeding,…
New behavioural trait adopted or rejected by observing heterospecific tutor fitness
2010
Animals can acquire behaviours from others, including heterospecifics, but should be discriminating in when and whom to copy. Successful individuals should be preferred as tutors, while adopting traits of poorly performing individuals should be actively avoided. Thus far it is unknown if such adaptive strategies are involved when individuals copy other species. Furthermore, rejection of traits based on tutor characteristics (negative bias) has not been shown in any non-human animal. Here we test whether a choice between two new, neutral behavioural alternatives—breeding-sites with alternative geometric symbols—is affected by observing the choice and fitness of a heterospecific tutor. A fiel…