Old males reduce melanin-pigmented traits and increase reproductive outcome under worse environmental conditions in common kestrels

Secondary sexual traits displayed by males and females may have evolved as a signal of individual quality. However, both individual quality and investment on producing or maintaining enhanced sexual traits change as individuals age. At the same time, the costs associated to produce sexual traits might be attenuated or increased if environmental conditions are benign or worse respectively. Accordingly, environmental conditions are expected to shape the association between the expression of sexual traits and their reproductive outcome as individuals age. Nonetheless, little is known about the environmental influence on the co-variation between sexual traits and reproductive outcome throughout the life of individuals. We studied the age-dependency of the number and size of back spots, a melanin-based and sexual trait in adults of common kestrels (Falco tinnunculus). We analysed the age-dependence of reproductive traits and the environmental influence, defined as vole abundance, using a 10-year individual-based dataset. We broke down age-related changes of reproductive traits into within- and between-individual variation to assess their contribution to population-level patterns. Our results showed a within-individual decrease in the number, but not the size, of back spots in males. The size of back spots was positively correlated with food availability in males. Reproductive performance of males increased as they aged, in agreement with the life-history theory but depending of vole abundance. Remarkably, we found that having fewer back spots was positively associated with clutch size only for old individuals under low-food conditions. We suggest that environmental variation may shape the association between the expression of a sexual signal and reproductive outcome. We speculate that the reliability of sexual traits is higher when environmental conditions are poor only for old individuals. Within an evolutionary context, we suggest that the expression of sexual traits might be constrained by environmental conditions at later stages of life.The long-term monitoring of the study population was financed by several projects of the Ministerio de Economía y Competitividad (CGL2004-04479/BOS, CGL2007-61395/BOS, CGL2010-15726/BOS, CGL2013-42451-P) of the Spanish Government.Peer reviewe

Providing longer post-fledging periods increases offspring survival at the expense of future fecundity

All relevant data are deposited at URI: http://hdl.handle.net/10261/169111; DOI: http://dx.doi.org/10.20350/digitalCSIC/8561.The cost of reproduction is a key concept in life-history trade-offs. However, our understanding of the reproductive costs is biased towards measures of reproductive effort obtained before offspring independence. During the post-fledging dependence period (PFDP), it is well known that parents feed and protect their offspring. However, the effort devoted to this reproductive activity has never been considered in the context of of the costs of reproduction. Moreover, the potential fitness benefits and costs for offspring and parents, respectively, of the duration of the PFDP are largely unknown. We estimated the duration of the PFDP over 5 years using wild common kestrels (Falco tinnunculus) and studied its association with survival probability and future parental reproductive performance. Our results show that longer PFDPs increase the survival probability of fledglings, probably due to the benefits obtained from parental care. In addition, we found that providing longer PFDPs was associated with reduced clutch sizes but not the number of fledglings in the subsequent breeding season in males. We suggest that increased parental expenditures on offspring during the PFDP may represent a potential cost of reproduction in breeding males.The long-term monitoring associated to this study was funded by projects CGL2004-04479/BOS, CGL2007-61395/BOS, CGL2010-15726/BOS and CGL2015-70639-P from the Ministerio de Economía y Competitividad.Peer reviewe

Urbanisation impacts plumage colouration in a songbird across Europe: evidence from a correlational, experimental, and meta-analytical approach

1. Urbanisation is accelerating across the globe, transforming landscapes, presenting organisms with novel challenges, shaping phenotypes and impacting fitness. Urban individuals are claimed to have duller carotenoid-based colouration, compared to their non-urban counterparts, the so-called ‘urban dullness’ phenomenon. However, at the intraspecific level, this generalisation is surprisingly inconsistent and often based on comparisons of single urban/non-urban populations or studies from a limited geographical area. 2. Here, we combine correlational, experimental and meta-analytical data on a common songbird, the great tit Parus major, to investigate carotenoid-based plumage colouration in urban and forest populations across Europe. 3. We find that, as predicted, urban individuals are paler than forest individuals, although there are large population-specific differences in the magnitude of the urban-forest contrast in colouration. Using one focal region (Malmö, Sweden), we reveal population-specific processes behind plumage colouration differences, which are unlikely to be the result of genetic or early-life conditions, but instead a consequence of environmental factors acting after fledging. 4. Finally, our meta-analysis indicates that the urban dullness phenomenon is well established in the literature, for great tits, with consistent changes in carotenoid-based plumage traits, particularly carotenoid chroma, in response to anthropogenic disturbances. 5. Overall, our results provide evidence for uniformity in the ‘urban dullness’ phenomenon but also highlight that the magnitude of the effect on colouration depends on local urban characteristics. Future long-term replicated studies, covering a wider range of species and feeding guilds, will be essential to further our understanding of the eco-evolutionary implications of this phenomenon

I Jornadas Científicas del Museo Nacional de Ciencias Naturales

I Jornadas Científicas del Museo Nacional de Ciencias Naturales, celebradas el 21-22 Febrero 2017, en el Museo Nacional de Ciencias Naturales (Madrid)El objetivo de las I Jornadas Científicas del Museo Nacional de Ciencias Naturales es dar a conocer las diferentes líneas de investigación que están realizando los distintos Departamentos de este Centro, además de dar la oportunidad de conocerse y facilitar la interacción entre todos. Las jornadas constan de 26 charlas (con sus presentaciones) y en principio, son representativas de todos los departamentos de forma equitativa de acuerdo con el número de miembros de cada uno de los participantes. Además dos o tres charlas "plenarias" de interés general. Se da prioridad a participar a los jóvenes investigadores, estudiantes de doctorado o jóvenes postdoctorandos. Participación de miembros de: Departamento de Biogeografía y Cambio Global, Dept. Ecología Evolutiva, Dept. Geología, Dept. Biodiversidad y Biología Evolutiva, Dept. Biogeoquímica y Ecología Microbiana, Dept. Paleobiología.01 Pequeña historia. 02 Programa de las Jornadas. 03 Libro de resumenes. 04 Cartel anunciador. 05 Menus de desayuno y almuerzo. 06 Balance de las Jornadas. 07 AgradecimientosPresentaciones disponibles: Álvarez-Cobelas: "Los científicos hispanos como insectos sociales?".-- Mikel Calle: "Cuando el río suena... agua lleva. Caracterizando la dinámica de los cauces efímeros mediterráneos”.-- María Cristina Casero: “"Aquí no hay quien viva: Microorganismos litobiónticos en el desierto de Atacama".-- Cepeda, Diego; Soler-Hurtado, M. Mar; Lattig, Patricia: "Un océano de gusanos marinos: la importancia de conocer la biodiversidad de anélidos asociados a corales".-- Flores, Omar; Rey, Ana; Curiel Yuste, Jorge; Valladares Ros, Fernando: “Modelización de la descomposición de la hojarasca en climas áridos”.-- Forner, Alicia; Aranda, Ismael; Valladares Ros, Fernando: “Árboles mediterráneos en la cuerda floja: sequías extremas, ¿un crimen con atenuantes?”.-- García-Ángulo, Daniel: “Ojos que no ven… Efecto del cambio climático y del manejo histórico de los encinares en el suelo bajo nuestros pies”.- García Morato, Sara: “Hienas, humanos y micromamíferos”.-- García-Tabernero, Antonio: “Aplicaciones de antropología virtual: colecciones virtuales y paleoneurología”.-- Garrido-Benavent, Isaac: Estudios filogeográficos de dos especies de hongos liquenizados muestran orígenes distintos de la biota liquénica antártica".-- Garrido, Fernando; García-Guinea, Javier; Gómez-González, Miguel A.: Presencia de arsénico en suelos contaminados de la provincia de Madrid.-- Gaspar, Leticia: “Técnicas radiométricas en el estudio de la erosión y la redistribución del suelo”.-- Doadrio, Ignacio; Pardos Blas, José Ramón: Desenredando el género Gambusia (Poeciliidae) en el noreste de México.-- Riesco López, Alberto; Bastir, Markus: Morfología virtual en 3D del Megatherium americanum del MNCNPeer reviewe

Species-specific song responses emerge as a by-product of tuning to the local dialect.

Oscine birds preferentially respond to certain sounds over others from an early age, which focuses subsequent learning onto sexually relevant songs.1-3 Songs vary both across species and, due to cultural evolution, among populations of the same species. As a result, early song responses are expected to be shaped by selection both to avoid the fitness costs of cross-species learning4 and to promote learning of population-typical songs.5 These sources of selection are not mutually exclusive but can result in distinct geographic patterns of song responses in juvenile birds: if the risks of interspecific mating are the main driver of early song discrimination, then discrimination should be strongest where closely related species co-occur.4 In contrast, if early discrimination primarily facilitates learning local songs, then it should be tuned to songs typical of the local dialect.5-7 Here, we experimentally assess the drivers of song discrimination in nestling pied flycatchers (Ficedula hypoleuca). We first demonstrate that early discrimination against the songs of the closely related collared flycatcher (F.albicollis) is not strongly affected by co-occurrence. Second, across six European populations, we show that nestlings' early song responses are tuned to their local song dialect and that responses to the songs of collared flycatchers are similarly weak as to those of other conspecific dialects. Taken together, these findings provide clear experimental support for the hypothesis that cultural evolution, in conjunction with associated learning predispositions, drives the emergence of pre-mating reproductive barriers.We thank the European Research Council (ERC, grant 851753) and Swedish Research Council (VR, grant 2019-03952) for grants to D.W. We thank the Ministerio de Ciencia e Innovación, Agencia Estatal de Investigación (MCIN/AEI//10.13039/501100011033) for grants to J.M. (FJCI-2017–34109), A.C. (IJC2018-035011-I and PID2019-109303GB-I00), and J.M.-P. (PID2019-104835GB-I00). We thank Mario Gallego-Abenza and Joana Fernandes for help with field work and analysis of the acoustic data

Plumage colouration and personality in early‐life: sexual differences in signalling

Several studies have shown that melanin‐based traits play a crucial role in social contexts as they are associated with dominance, personality and social behaviour. However, most of these studies have focused on adults, and the role of these traits in juveniles remains scarcely explored. Here, we explore the association between two melanin‐based traits and nestling personality in Common Kestrels Falco tinnunculus. Our results show that female nestlings with blacker plumages displayed bolder personalities, providing evidence of sex‐dependent phenotypic integration of these two traits in males and females. We consider that this differential integration may arise from different selection pressures acting on males and females on plumage colouration during adulthood and that nestling colouration can act as a status signal within the juvenile age‐class.The study was financed by the Spanish Ministerio de Economía y Competitividad (Project: CGL2013-42451-P). DLI is supported by a postdoctoral contract of the REMEDINAL3-CM program of Comunidad Autónoma de Madrid (REF: S2013/MAE-2719)Peer reviewe

Providing longer post-fledging periods increases offspring survival at the expense of future fecundity [dataset]

[Access and reuse conditions] This database and its components are subject to a Creative Commons Attribution International licence 4.0.The cost of reproduction is a key concept in life-history trade-offs. However, our understanding of the reproductive costs is biased towards measures of reproductive effort obtained before offspring independence. During the post-fledging dependence period (PFDP) is well known that parents feed and protect their offspring. However, the effort devoted to this reproductive activity has never been considered under the scheme of the costs of reproduction, and the potential fitness benefits and costs, for offspring and parents respectively, of the duration of PFDP remain barely known. We estimated the duration of the PFDP during 5 years using wild common kestrels (Falco tinnunculus) and studied its association with survival probability and future parental reproductive performance. Our results show that longer PFDPs increased the survival probability of fledglings, probably due to the benefits obtained by parental care. Also, we found that providing longer PFDPs was associated with reduced clutch sizes but not number of fledglings the subsequent breeding season in males. We suggest that increased parental expenditure on offspring during the PFDP may represent a potential cost of reproduction in breeding males.The long-term monitoring associated to this study was funded by projects CGL2004- 04479/BOS, CGL2007-61395/BOS, CGL2010-15726/BOS and CGL2015-70639-P from the Ministerio de Economía y CompetitividadPeer reviewe

Female plumage coloration signals status to conspecifics

Intrasexual competition in female birds is a widespread phenomenon but remains scarcely explored. Females compete for limited resources and the expression of signals that indicate their social status will be favoured by natural selection, generating a dominance hierarchy among individuals. However, which signals might be involved in female–female competition is unclear. In this study, we tested the role of rump coloration as a badge of status within a context of intrasexual competition using common kestrels, Falco tinnunculus, in two populations over 3 years. We used natural decoys with two different ‘phenotypes’, since the expression of this melanin-pigmented trait within the brown–grey range has been suggested to be a reliable proxy of individual quality in female common kestrels. By showing natural decoys with grey and brown rumps to breeding females, we simulated territorial invasions of high- and low-quality females, respectively. Our results show that rump coloration generates a differential response during territorial invasions. Specifically, we found that grey-rumped decoys (high quality) elicited lower levels of aggressiveness. In addition, female agonistic response was negatively associated with clutch size. Based on our results, we suggest that female rump coloration works as a badge of status in breeding female kestrels. This trait may signal female competitive ability and can generate a dominance hierarchy among individuals in our population. We also suggest that aggressiveness can be costly to females in terms of reproductive outcome. Overall, we provide evidence that melanin-pigmented traits in females can play a key role in intrasexual competition.This study was financed by the Spanish Ministerio de Economía y Competitividad (Project: CGL2010-15726/BOS).Peer Reviewe

Within-individual age variation of two melanin-pigmented traits convey different information in adults of common kestrels (Falco tinnunculus)

Resumen del trabajo presentado al XV Congreso Nacional y XII Iberoamericano de Etología, celebrado en Barcelona (España) del 3 al 5 de septiembre de 2014.Secondary sexual traits displayed by males and females may have evolved to inform about individual quality. Individuals of primer quality are expected to have benefits in intra- and inter-sexual interactions and ultimately in fitness. However, the covariation of the expression of sexual traits and individual fitness as individual’s age is still poorly known and controversial. Within a life-history perspective, ornament expression is expected to increase as individual’s age, despite decreasing their residual reproductive value. Nevertheless, environmental conditions may also drive both reproduction and the expression of phenotypes as individual’s age. However, little is known about the environmental influence on age-dependence variation of sexual traits. Here we study the age-dependence of the number and size of back spots, a melanin-pigmented and sexual trait in adults of both males and females of common kestrels (Falco tinnunculus). We also analysed the age-dependence of reproductive traits and the environmental influence, stated as food availability (vole abundance), using a 10-year individual-based dataset. We decomposed age-related changes into within- and between-individual variation to assess their contribution to population-level patterns. Our results showed a within-individual decrease in the number but not the size of back spots, only in males. Instead, size but not number of back spots was positively associated with food availability. In addition, reproductive performance of males increases as they age. No significant relationship was found for females neither in the age-dependence nor in the reproductive performance. We suggest that the number of back spots in males can be an age indicator and perhaps an index of reproductive quality. We suggest that genetic and environmental factors may explain the expression of two different characteristics of a same trait. The differences in the responses to age and environment between males and females studied traits may arise by different behavioural functions.Peer reviewe

Divergent patterns of age and environmental dependence in two melanin-based traits in males of common kestrels (Falco tinnunculus)

Trabajo presentado al XXII Congreso Español de Ornitología: "Aves y ser humano: una relación variable", celebrado en Madrid del 6 al 9 de diciembre del 2014.[EN]: Secondary sexual traits may have evolved to inform about individual quality. Individuals of primer quality are expected to have benefits in intra- and inter-sexual interactions and ultimately in fitness. However, the covariation of the expression of sexual traits and individual fitness as individuals age is still poorly known and controversial. Within a life-history perspective, ornament expression is expected to increase as individuals age, despite decreasing their residual reproductive value. Nevertheless, environmental conditions may also drive both reproduction and the expression of phenotypes throughout their lives. However, little is known about the environmental influence on age-dependence variation of sexual traits. Based on the analysis of a 10-year individual data set of adult common kestrels (Falco tinnunculus), we study 1) the age-dependence of the number and size of back spots, a melanin-pigmented and sexual trait in adult males; and 2) the environmental influence on the expression of these traits as individual age. We considered vole abundance during the length of the study period as proxy of environmental variation. We decomposed age-related changes into within and between individual variation to assess their contribution to population-level patterns. Our results showed a within-individual decrease of the number but not size of back spots. Instead, size but not number of back spots was positively associated with food availability. In addition, reproductive performance increases as individuals age. We suggest that the number of back spots can be an age indicator and perhaps an index of reproductive quality and size of back spot reflects the environmental conditions at the time of moulting. Our results suggest that genetic and environmental factors may explain the expression of different characteristics of a same trait.Peer reviewe