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Morales J.,CSIC - National Museum of Natural Sciences | Ruuskanen S.,University of Turku | Laaksonen T.,University of Turku | Eeva T.,University of Turku | And 17 more authors.
Journal of Avian Biology | Year: 2013

The expression and impact of maternal effects may vary greatly between populations and environments. However, little is known about large-scale geographical patterns of variation in maternal deposition to eggs. In birds, as in other oviparous animals, the outermost maternal component of an egg is the shell, which protects the embryo, provides essential mineral resources and allows its interaction with the environment in the form of gas exchange. In this study, we explored variation of eggshell traits (mass, thickness, pore density and pigmentation) across 15 pied flycatcher populations at a large geographic scale. We found significant between-population variation in all eggshell traits, except in pore density, suggesting spatial variation in their adaptive benefits or in the females' physiological limitations during egg laying. Between- population variation in shell structure was not due to geographic location (latitude and longitude) or habitat type. However, eggshells were thicker in populations that experienced higher ambient temperature during egg laying. This could be a result of maternal resource allocation to the shell being constrained under low temperatures or of an adaptation to reduce egg water loss under high temperatures. We also found that eggshell colour intensity was positively associated with biliverdin pigment concentration, shell thickness and pore density. To conclude, our findings reveal large- scale between-population variation of eggshell traits, although we found little environmental dependency in their expression. Our findings call for further studies that explore other environmental factors (e.g. calcium availability and pollution levels) and social factors like sexual selection intensity that may account for differences in shell structure between populations. © 2013 The Authors. Journal of Avian Biology © 2013 Nordic Society Oikos.

Sanchez-Fernandez D.,Museo Nacional de Ciencias Naturales CSIC | Lobo J.M.,Museo Nacional de Ciencias Naturales CSIC | Abellan P.,University of Murcia | Abellan P.,University of Aarhus | Millan A.,University of Murcia
Biological Journal of the Linnean Society | Year: 2011

Historically, there has been considerable disagreement between researchers about the criteria used to discriminate among species. Decisions based on traditional morphological and genetic data alone can be potentially problematic, especially if the hypotheses are contradictory. Today, taxonomy is integrating new methods from different disciplines that study species' limits and evolution; this diverse range of evidence aids researchers in the recognition of species. Differences in niche characteristics could become a new and useful criterion in helping to decide the status of conflicting taxonomical entities. Ochthebius glaber (family Hydraenidae) is an endangered water beetle typical from southeast Iberian hypersaline streams that shows three clear discrete genetic units within its distribution range. However, there is no evidence to date that these lineages of O. glaber exhibit any adaptive morphological or ecological divergence. Using a modelling approach directed to generate niche representation from distributional data, we found a significant environmental niche divergence for allopatric lineages of O. glaber that followed an aridity gradient. Although we can not conclude firmly at present that the separate populations of O. glaber studied represent separate, reproductively isolated species, the present study complements and supports previous phylogeographic analyses through the inclusion of measures of another form of evolutionary change; in this case, ecological diversification. Despite the existence of some methodological limitations, also discussed in the present study, we emphasize the importance of recent conceptual advances that allow taxonomy to improve species delimitation practices through the integration of theory and methods from disciplines that study the origin and evolution of species. © 2011 The Linnean Society of London.

Calabuig G.,Institute Investigacion en Recursos Cinegeticos IREC CSIC | Ortego J.,Museo Nacional de Ciencias Naturales CSIC | Aparicio J.M.,Institute Investigacion en Recursos Cinegeticos IREC CSIC | Cordero P.J.,Institute Investigacion en Recursos Cinegeticos IREC CSIC
Animal Behaviour | Year: 2010

The exploratory activity of individuals aimed at collecting information about potential future breeding sites is known as prospecting. We studied prospecting behaviour in the colonial lesser kestrel, Falco naumanni, using detailed information from radiomarked individuals, whose breeding attempts we terminated at the chick stage, and intensive videotape recording of nests. Half of the radiomarked individuals actively prospected nests in both their own and foreign colonies and they visited colonies up to 7400 m away from their own breeding colony. The presence and number of prospectors arriving at a given nest were influenced by parameters at both the colony and the nest scale. Prospector visits per nest increased with colony productivity and decreased with colony size. The latter does not necessarily mean that prospectors avoid large colonies but rather may be consequence of a dilution effect in colonies where more potential nests can be prospected. The number of prospectors attracted per nest was positively associated with colony connectivity, indicating that both high spatial colony isolation and a small number of breeding pairs in nearby colonies reduced the arrival of prospectors at a given nest. Finally, prospector visits per nest increased and then decreased with parental feeding rates, indicating this parental activity can attract prospectors up to a certain threshold at which nest owners visit their nests frequently enough to keep prospectors away. Overall, this study suggests that prospecting is the mechanism of acquiring public information that could ultimately determine breeding dispersal decisions and the growth and dynamics observed in breeding aggregations. © 2009 The Association for the Study of Animal Behaviour.

Calabuig G.,Institute Investigacion en Recursos Cinegeticos IREC CSIC | Ortego J.,Museo Nacional de Ciencias Naturales CSIC | Cordero P.J.,Institute Investigacion en Recursos Cinegeticos IREC CSIC | Aparicio J.M.,Institute Investigacion en Recursos Cinegeticos IREC CSIC
Animal Behaviour | Year: 2010

Understanding the process of colonization of new habitat patches is critical to clarify the proximate mechanisms involved in the distribution of a species and particularly in the formation of breeding aggregations. We studied the process of colony foundation in a long-term monitored population of lesser kestrels, Falco naumanni. For this purpose, we first analysed which habitat/demographic features influence the occupation of empty habitat patches experimentally supplied with nestboxes. Second, we studied the individual characteristics of founders and the reproductive consequences of occupation of new breeding patches in comparison with individuals settled in already established colonies. We found that the probability of occupation of experimental breeding patches increased with the relative cover of cereal crops. Regardless of sex, founders and individuals that settled in pre-existing colonies did not differ in body condition or age. However, there was a higher proportion of unringed kestrels in new than in pre-existing colonies, suggesting that founders are mostly immigrants from distant populations. Founders and nonfounders had similar breeding success, but the former had a lower parasitic burden of feather lice, indicating that occupying new breeding patches could reduce parasite pressure and/or transmission. Our results suggest habitat characteristics influence settlement decisions in the absence of pre-existing social cues, but do not support the idea that founders are suboptimal individuals unable to gain access to previously established colonies. © 2010 The Association for the Study of Animal Behaviour.

Ortego J.,Museo Nacional de Ciencias Naturales CSIC | Ortego J.,Institute Investigacion en Recursos Cinegeticos IREC | Garcia-Navas V.,University of Castilla - La Mancha | Ferrer E.S.,University of Castilla - La Mancha | And 2 more authors.
Animal Behaviour | Year: 2011

The study of the genetic consequences of dispersal is a central topic in evolutionary, conservation and behavioural research. However, few studies have simultaneously considered dispersal movements from marked individuals and contemporary patterns of gene flow. We analysed the link between dispersal behaviour and gene flow in four populations of blue tits with different degrees of connectivity. For this purpose, we monitored four breeding patches and used genotypic and capture-mark-recapture data to study the genetic consequences of dispersal at different spatial scales. Data on natal dispersal movements revealed that both males and females dispersed less than expected under a random pattern of settlement at the two large spatial scales considered: the whole study area and the two main localities. However, natal dispersal distance was lower than expected under random settlement within natal patches in males whereas an opposite pattern was found for females. Accordingly, microsatellite data revealed limited gene flow between the localities studied and an isolation-by-distance pattern of genetic structure that was particularly strong at the large spatial scale (i.e. considering geographically distant breeding patches). Finally, the strong male philopatry was reflected by a stronger genetic structure and a lower admixed ancestry in this sex. Overall, we found evidence that restricted dispersal and fragmentation may have both contributed to reduce interpopulation gene flow at different spatial scales in a forest species and that there is concordance between genetic studies and those based on capture-mark-recapture. © 2011 The Association for the Study of Animal Behaviour.

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