This page has only limited features, please log in for full access.
Acoustic and visual signals are well known to play important roles in social communication in birds. Growing evidence suggests that many bird species, including species of songbirds, additionally have a well-developed sense of smell. However, we are still at the beginning of understanding the potential importance of chemical communication in the social lives of birds, for example in mate choice. The secretion of the preen gland may be an important contributor to the chemical phenotype of birds. Here, we report on a first characterisation of the chemical composition of the preen gland secretion of the Blue Tit (Cyanistes caeruleus), a common songbird which is an often used model species in animal behaviour and ecology, in particular also in studies of sexual selection and (extra-pair) mate choice. We found sex differences in the composition of the preen gland secretion in breeding Blue Tits. Females further tended to have a larger number of putative compounds in their secretions compared to males. We briefly discuss the possible implications of these findings and speculate that the chemical composition of the preen gland secretion may be a sexually selected trait in Blue Tits. Our preliminary findings warrant follow-up research into the patterns of within- and among individual variation in the chemical composition of the preen gland secretion as well as the identification of the main chemical compounds involved.
Barbara A. Caspers; Reinaldo Marfull; Tim Dannenhaus; Jan Komdeur; Peter Korsten. Chemical analysis reveals sex differences in the preen gland secretion of breeding Blue Tits. Journal of Ornithology 2021, 1 -8.
AMA StyleBarbara A. Caspers, Reinaldo Marfull, Tim Dannenhaus, Jan Komdeur, Peter Korsten. Chemical analysis reveals sex differences in the preen gland secretion of breeding Blue Tits. Journal of Ornithology. 2021; ():1-8.
Chicago/Turabian StyleBarbara A. Caspers; Reinaldo Marfull; Tim Dannenhaus; Jan Komdeur; Peter Korsten. 2021. "Chemical analysis reveals sex differences in the preen gland secretion of breeding Blue Tits." Journal of Ornithology , no. : 1-8.
The existence of among-individual variation in behaviour within populations is poorly understood. Recent theory suggests that fine-scale individual differences in investment into current versus future reproduction may lead to a ‘slow-fast’-pace-of-life continuum, also referred to as the ‘pace-of-life-syndrome’ (POLS) hypothesis. According to this idea, individuals are predicted to differ in their level of risk-taking, which may drive among-individual variation and covariation of behaviours. Consistent individual differences in aggression, an ecologically relevant and potentially risky behaviour, have been reported across the animal kingdom. Here we test whether such individual differences in aggression are a manifestation of underlying differences in risk-taking. In a wild blue tit (Cyanistes caeruleus) population, we used standard behavioural tests to investigate if male territorial aggressiveness and risk-taking during breeding are positively related. At the start of breeding, we simulated conspecific territorial intrusions to obtain repeated measures of male aggressiveness. Subsequently, we measured male risk-taking as their latency to resume brood provisioning after presenting two different predators at their nest: human and sparrowhawk, a common predator of adult songbirds. First, we found substantial repeatability for male aggressiveness (R = 0.56 ± 0.08 SE). Second, while males took longer to resume provisioning after presentation of a sparrowhawk mount as compared to a human observer, risk-taking was repeatable across these two predator contexts (R = 0.51 ± 0.13 SE). Finally, we found no evidence for a correlation between male aggressiveness and risk-taking, thereby providing little support to a main prediction of the POLS hypothesis. Significance statement Consistent, and often correlated, individual differences in basal behaviours, such as aggression, exploration and sociability, are found across the animal kingdom. Why individuals consistently differ in their behaviour is poorly understood, as behavioural traits would seem inherently flexible. The ‘pace-of-life syndrome’ (POLS) hypothesis proposes observed behavioural variation to reflect differences in risk-taking associated with individual reproductive strategies. We tested this idea in a wild blue tit population by investigating whether individual males that were more aggressive toward territorial intruders also took more risk when provisioning their nestlings under a threat of predation. While we found consistent individual differences in both aggressiveness and risk-taking, these behaviours were not significantly correlated. Therefore, our study demonstrates among-individual variation in ecologically relevant behaviours in wild blue tits but provides little support for the POLS hypothesis.
Stephen M. Salazar; Julia I. Camacho García; Miriam Kuspiel; Rienk W. Fokkema; Jan Komdeur; Peter Korsten. Male aggressiveness and risk-taking during reproduction are repeatable but not correlated in a wild bird population. Behavioral Ecology and Sociobiology 2021, 75, 1 -15.
AMA StyleStephen M. Salazar, Julia I. Camacho García, Miriam Kuspiel, Rienk W. Fokkema, Jan Komdeur, Peter Korsten. Male aggressiveness and risk-taking during reproduction are repeatable but not correlated in a wild bird population. Behavioral Ecology and Sociobiology. 2021; 75 (7):1-15.
Chicago/Turabian StyleStephen M. Salazar; Julia I. Camacho García; Miriam Kuspiel; Rienk W. Fokkema; Jan Komdeur; Peter Korsten. 2021. "Male aggressiveness and risk-taking during reproduction are repeatable but not correlated in a wild bird population." Behavioral Ecology and Sociobiology 75, no. 7: 1-15.
Parents are expected to make fine-tuned decisions by weighing the benefits of providing care to increase offspring survival against that of deserting to pursue future mating opportunities. A higher incentive for the rarer sex in the population indicates an impact of mating opportunities on parental care decisions. However, in a dynamic breeding system, deserting the offspring and searching for a new mate would influence mating opportunities for both sexes. Sex-specific costs and benefits are expected to influence males’ and females’ parenting strategies in different ways. Here, we investigated Chinese penduline tits, Remiz consobrinus, which exhibit flexible parental care strategies: uniparental care by the male or female, biparental care, and biparental desertion occur in the same population. We show that male penduline tits change their parental behavior over the breeding season; they desert clutches produced early in the season but care for the late season clutches. The change in male parenting behavior is consistent with the seasonal decline in mating opportunities. In contrast, parenting by females did not change over the breeding season, nor was it associated with seasonal variation in mate availability. Taken together, mating opportunities have different associations with parental behavior of male and female Chinese penduline tits. We recommend an inclusion of mating opportunities for both sexes simultaneously in order to understand one of the fundamental decisions in parental care evolution—care or desert. Divorce is a common feature of both human and nonhuman animal societies. Theoretical studies suggest that one of the drivers of divorce is enhanced mating opportunity, i.e., parents with higher mating opportunities are more likely to abandon their family than those with low mating opportunities. Here, we investigate the dynamics of parental behavior and mating opportunities in a wild population of a small songbird, the Chinese penduline tit Remiz consobrinus. This species exhibits one of the most diverse avian breeding systems wherein both uniparental (male or female) and biparental rearing can be seen in a single population. We show that male penduline tits abandon their offspring in response to enhanced mating opportunities while the female parental behavior remains unaffected. This implies the relationship between mating opportunities and parental care is more complex than currently acknowledged and requires further investigation.
Jia Zheng; Jan Komdeur; Tamás Székely; Maaike A. Versteegh; Donglai Li; Hui Wang; Zhengwang Zhang. Males and females of a polygamous songbird respond differently to mating opportunities. Behavioral Ecology and Sociobiology 2021, 75, 1 -13.
AMA StyleJia Zheng, Jan Komdeur, Tamás Székely, Maaike A. Versteegh, Donglai Li, Hui Wang, Zhengwang Zhang. Males and females of a polygamous songbird respond differently to mating opportunities. Behavioral Ecology and Sociobiology. 2021; 75 (4):1-13.
Chicago/Turabian StyleJia Zheng; Jan Komdeur; Tamás Székely; Maaike A. Versteegh; Donglai Li; Hui Wang; Zhengwang Zhang. 2021. "Males and females of a polygamous songbird respond differently to mating opportunities." Behavioral Ecology and Sociobiology 75, no. 4: 1-13.
Understanding trade‐offs in wild populations is difficult, but important if we are to understand the evolution of life histories and the impact of ecological variables upon them. Markers that reflect physiological state and predict future survival would be of considerable benefit to unraveling such trade‐offs and could provide insight into individual variation in senescence. However, currently used markers often yield inconsistent results. One underutilized measure is hematocrit, the proportion of blood comprising erythrocytes, which relates to the blood's oxygen‐carrying capacity and viscosity, and to individual endurance. Hematocrit has been shown to decline with age in cross‐sectional studies (which may be confounded by selective appearance/disappearance). However, few studies have tested whether hematocrit declines within individuals or whether low hematocrit impacts survival in wild taxa. Using longitudinal data from the Seychelles warbler (Acrocephalus sechellensis), we demonstrated that hematocrit increases with age in young individuals (<1.5 years) but decreases with age in older individuals (1.5–13 years). In breeders, hematocrit was higher in males than females and varied relative to breeding stage. High hematocrit was associated with lower survival in young individuals, but not older individuals. Thus, while we did not find support for hematocrit as a marker of senescence, high hematocrit is indicative of poor condition in younger individuals. Possible explanations are that these individuals were experiencing dehydration and/or high endurance demands prior to capture, which warrants further investigation. Our study demonstrates that hematocrit can be an informative metric for life‐history studies investigating trade‐offs between survival, longevity, and reproduction.
Thomas J. Brown; Martijn Hammers; Martin Taylor; Hannah L. Dugdale; Jan Komdeur; David S. Richardson. Hematocrit, age, and survival in a wild vertebrate population. Ecology and Evolution 2020, 11, 214 -226.
AMA StyleThomas J. Brown, Martijn Hammers, Martin Taylor, Hannah L. Dugdale, Jan Komdeur, David S. Richardson. Hematocrit, age, and survival in a wild vertebrate population. Ecology and Evolution. 2020; 11 (1):214-226.
Chicago/Turabian StyleThomas J. Brown; Martijn Hammers; Martin Taylor; Hannah L. Dugdale; Jan Komdeur; David S. Richardson. 2020. "Hematocrit, age, and survival in a wild vertebrate population." Ecology and Evolution 11, no. 1: 214-226.
The integration and synthesis of the data in different areas of science is drastically slowed and hindered by a lack of standards and networking programmes. Long‐term studies of individually marked animals are not an exception. These studies are especially important as instrumental for understanding evolutionary and ecological processes in the wild. Further, their number and global distribution provides a unique opportunity to assess the generality of patterns and to address broad‐scale global issues (e.g. climate change). To solve data integration issues and enable a new scale of ecological and evolutionary research based on long‐term studies of birds, we have created the SPI‐Birds Network and Database (www.spibirds.org) – a large‐scale initiative that connects data from, and researchers working on, studies of wild populations of individually recognizable (usually ringed) birds. Within year and a half since the establishment, SPI‐Birds has recruited over 120 members, and currently hosts data on almost 1,5 million individual birds collected in 80 populations over 2000 cumulative years, and counting. SPI‐Birds acts as a data hub and a catalogue of studied populations. It prevents data loss, secures easy data finding, use and integration, and thus facilitates collaboration and synthesis. We provide community‐derived data and meta‐data standards and improve data integrity guided by the principles of Findable, Accessible, Interoperable, and Reusable (FAIR), and aligned with the existing metadata languages (e.g. ecological meta‐data language). The encouraging community involvement stems from SPI‐Bird's decentralized approach: research groups retain full control over data use and their way of data management, while SPI‐Birds creates tailored pipelines to convert each unique data format into a standard format. We outline the lessons learned, so that other communities (e.g. those working on other taxa) can adapt our successful model. Creating community‐specific hubs (such as ours, COMADRE for animal demography, etc.) will aid much‐needed large‐scale ecological data integration.
Antica Culina; Frank Adriaensen; Liam D. Bailey; Malcolm D. Burgess; Anne Charmantier; Ella F. Cole; Tapio Eeva; Erik Matthysen; Chloé R. Nater; Ben C. Sheldon; Bernt‐Erik Sæther; Stefan J. G. Vriend; Zuzana Zajkova; Peter Adamík; Lucy M. Aplin; Elena Angulo; Alexandr Artemyev; Emilio Barba; Sanja Barišić; Eduardo Belda; Cemal Can Bilgin; Josefa Bleu; Christiaan Both; Sandra Bouwhuis; Claire J. Branston; Juli Broggi; Terry Burke; Andrey Bushuev; Carlos Camacho; Daniela Campobello; David Canal; Alejandro Cantarero; Samuel P. Caro; Maxime Cauchoix; Alexis Chaine; Mariusz Cichoń; Davor Ćiković; Camillo A. Cusimano; Caroline Deimel; André A. Dhondt; Niels J. Dingemanse; Blandine Doligez; Davide M. Dominoni; Claire Doutrelant; Szymon M. Drobniak; Anna Dubiec; Marcel Eens; Kjell Einar Erikstad; Silvia Espín; Damien R. Farine; Jordi Figuerola; Pınar Kavak Gülbeyaz; Arnaud Grégoire; Ian R. Hartley; Michaela Hau; Gergely Hegyi; Sabine Hille; Camilla A. Hinde; Benedikt Holtmann; Tatyana Ilyina; Caroline Isaksson; Arne Iserbyt; Elena Ivankina; Wojciech Kania; Bart Kempenaers; Anvar Kerimov; Jan Komdeur; Peter Korsten; Miroslav Král; Miloš Krist; Marcel Lambrechts; Carlos E. Lara; Agu Leivits; András Liker; Jaanis Lodjak; Marko Mägi; Mark C. Mainwaring; Raivo Mänd; Bruno Massa; Sylvie Massemin; Jesús Martínez‐Padilla; Tomasz D. Mazgajski; Adèle Mennerat; Juan Moreno; Alexia Mouchet; Shinichi Nakagawa; Jan‐Åke Nilsson; Johan F. Nilsson; Ana Cláudia Norte; Kees van Oers; Markku Orell; Jaime Potti; John L. Quinn; Denis Réale; Tone Kristin Reiertsen; Balázs Rosivall; Andrew F Russell; Seppo Rytkönen; Pablo Sánchez‐Virosta; Eduardo S. A. Santos; Julia Schroeder; Juan Carlos Senar; Gábor Seress; Tore Slagsvold; Marta Szulkin; Céline Teplitsky; Vallo Tilgar; Andrey Tolstoguzov; János Török; Mihai Valcu; Emma Vatka; Simon Verhulst; Hannah Watson; Teru Yuta; José M. Zamora‐Marín; Marcel E. Visser. Connecting the data landscape of long‐term ecological studies: The SPI‐Birds data hub. Journal of Animal Ecology 2020, 1 .
AMA StyleAntica Culina, Frank Adriaensen, Liam D. Bailey, Malcolm D. Burgess, Anne Charmantier, Ella F. Cole, Tapio Eeva, Erik Matthysen, Chloé R. Nater, Ben C. Sheldon, Bernt‐Erik Sæther, Stefan J. G. Vriend, Zuzana Zajkova, Peter Adamík, Lucy M. Aplin, Elena Angulo, Alexandr Artemyev, Emilio Barba, Sanja Barišić, Eduardo Belda, Cemal Can Bilgin, Josefa Bleu, Christiaan Both, Sandra Bouwhuis, Claire J. Branston, Juli Broggi, Terry Burke, Andrey Bushuev, Carlos Camacho, Daniela Campobello, David Canal, Alejandro Cantarero, Samuel P. Caro, Maxime Cauchoix, Alexis Chaine, Mariusz Cichoń, Davor Ćiković, Camillo A. Cusimano, Caroline Deimel, André A. Dhondt, Niels J. Dingemanse, Blandine Doligez, Davide M. Dominoni, Claire Doutrelant, Szymon M. Drobniak, Anna Dubiec, Marcel Eens, Kjell Einar Erikstad, Silvia Espín, Damien R. Farine, Jordi Figuerola, Pınar Kavak Gülbeyaz, Arnaud Grégoire, Ian R. Hartley, Michaela Hau, Gergely Hegyi, Sabine Hille, Camilla A. Hinde, Benedikt Holtmann, Tatyana Ilyina, Caroline Isaksson, Arne Iserbyt, Elena Ivankina, Wojciech Kania, Bart Kempenaers, Anvar Kerimov, Jan Komdeur, Peter Korsten, Miroslav Král, Miloš Krist, Marcel Lambrechts, Carlos E. Lara, Agu Leivits, András Liker, Jaanis Lodjak, Marko Mägi, Mark C. Mainwaring, Raivo Mänd, Bruno Massa, Sylvie Massemin, Jesús Martínez‐Padilla, Tomasz D. Mazgajski, Adèle Mennerat, Juan Moreno, Alexia Mouchet, Shinichi Nakagawa, Jan‐Åke Nilsson, Johan F. Nilsson, Ana Cláudia Norte, Kees van Oers, Markku Orell, Jaime Potti, John L. Quinn, Denis Réale, Tone Kristin Reiertsen, Balázs Rosivall, Andrew F Russell, Seppo Rytkönen, Pablo Sánchez‐Virosta, Eduardo S. A. Santos, Julia Schroeder, Juan Carlos Senar, Gábor Seress, Tore Slagsvold, Marta Szulkin, Céline Teplitsky, Vallo Tilgar, Andrey Tolstoguzov, János Török, Mihai Valcu, Emma Vatka, Simon Verhulst, Hannah Watson, Teru Yuta, José M. Zamora‐Marín, Marcel E. Visser. Connecting the data landscape of long‐term ecological studies: The SPI‐Birds data hub. Journal of Animal Ecology. 2020; ():1.
Chicago/Turabian StyleAntica Culina; Frank Adriaensen; Liam D. Bailey; Malcolm D. Burgess; Anne Charmantier; Ella F. Cole; Tapio Eeva; Erik Matthysen; Chloé R. Nater; Ben C. Sheldon; Bernt‐Erik Sæther; Stefan J. G. Vriend; Zuzana Zajkova; Peter Adamík; Lucy M. Aplin; Elena Angulo; Alexandr Artemyev; Emilio Barba; Sanja Barišić; Eduardo Belda; Cemal Can Bilgin; Josefa Bleu; Christiaan Both; Sandra Bouwhuis; Claire J. Branston; Juli Broggi; Terry Burke; Andrey Bushuev; Carlos Camacho; Daniela Campobello; David Canal; Alejandro Cantarero; Samuel P. Caro; Maxime Cauchoix; Alexis Chaine; Mariusz Cichoń; Davor Ćiković; Camillo A. Cusimano; Caroline Deimel; André A. Dhondt; Niels J. Dingemanse; Blandine Doligez; Davide M. Dominoni; Claire Doutrelant; Szymon M. Drobniak; Anna Dubiec; Marcel Eens; Kjell Einar Erikstad; Silvia Espín; Damien R. Farine; Jordi Figuerola; Pınar Kavak Gülbeyaz; Arnaud Grégoire; Ian R. Hartley; Michaela Hau; Gergely Hegyi; Sabine Hille; Camilla A. Hinde; Benedikt Holtmann; Tatyana Ilyina; Caroline Isaksson; Arne Iserbyt; Elena Ivankina; Wojciech Kania; Bart Kempenaers; Anvar Kerimov; Jan Komdeur; Peter Korsten; Miroslav Král; Miloš Krist; Marcel Lambrechts; Carlos E. Lara; Agu Leivits; András Liker; Jaanis Lodjak; Marko Mägi; Mark C. Mainwaring; Raivo Mänd; Bruno Massa; Sylvie Massemin; Jesús Martínez‐Padilla; Tomasz D. Mazgajski; Adèle Mennerat; Juan Moreno; Alexia Mouchet; Shinichi Nakagawa; Jan‐Åke Nilsson; Johan F. Nilsson; Ana Cláudia Norte; Kees van Oers; Markku Orell; Jaime Potti; John L. Quinn; Denis Réale; Tone Kristin Reiertsen; Balázs Rosivall; Andrew F Russell; Seppo Rytkönen; Pablo Sánchez‐Virosta; Eduardo S. A. Santos; Julia Schroeder; Juan Carlos Senar; Gábor Seress; Tore Slagsvold; Marta Szulkin; Céline Teplitsky; Vallo Tilgar; Andrey Tolstoguzov; János Török; Mihai Valcu; Emma Vatka; Simon Verhulst; Hannah Watson; Teru Yuta; José M. Zamora‐Marín; Marcel E. Visser. 2020. "Connecting the data landscape of long‐term ecological studies: The SPI‐Birds data hub." Journal of Animal Ecology , no. : 1.
Life‐history theory predicts a trade‐off between current and future reproduction to maximize lifetime fitness. In cooperatively breeding species, where offspring care is shared between breeders and helpers, helper presence may influence the female breeders’ egg investment, and consequently, survival and future reproductive success. For example, female breeders may reduce egg investment in response to helper presence if this reduction is compensated by helpers during provisioning. Alternatively, female breeders may increase egg investment in response to helper presence if helpers allow the breeders to raise more or higher quality offspring successfully. In the facultatively cooperative‐breeding Tibetan ground tit Pseudopodoces humilis, previous studies found that helpers improve total nestling provisioning rates and fledgling recruitment, but have no apparent effects on the number and body mass of fledglings produced, while breeders with helpers show reduced provisioning rates and higher survival. Here, we investigated whether some of these effects may be explained by female breeders reducing their investment in eggs in response to helper presence. In addition, we investigated whether egg investment is associated with the female breeder's future fitness. Our results showed that helper presence had no effect on the female breeders’ egg investment, and that egg investment was not associated with breeder survival and reproductive success. Our findings suggest that the responses of breeders to helping should be investigated throughout the breeding cycle, because the conclusions regarding the breeders’ adjustment of reproductive investment in response to being helped may depend on which stage of the breeding cycle is considered. This article is protected by copyright. All rights reserved.
Qingtian Zhao; Martijn Hammers; Chen Li; Xixia Zeng; Chenxi Hao; Xin Lu; Jan Komdeur. Egg investment in response to helper presence in cooperatively breeding Tibetan ground tits. Journal of Avian Biology 2019, 50, 1 .
AMA StyleQingtian Zhao, Martijn Hammers, Chen Li, Xixia Zeng, Chenxi Hao, Xin Lu, Jan Komdeur. Egg investment in response to helper presence in cooperatively breeding Tibetan ground tits. Journal of Avian Biology. 2019; 50 (6):1.
Chicago/Turabian StyleQingtian Zhao; Martijn Hammers; Chen Li; Xixia Zeng; Chenxi Hao; Xin Lu; Jan Komdeur. 2019. "Egg investment in response to helper presence in cooperatively breeding Tibetan ground tits." Journal of Avian Biology 50, no. 6: 1.
Natural populations are persistently exposed to environmental pollution, which may adversely impact animal physiology and behaviour and even compromise survival. Responding appropriately to any stressor ultimately might tip the scales for survival, as mistimed behaviour and inadequate physiological responses may be detrimental. Yet effects of legacy contamination on immediate physiological and behavioural stress coping abilities during acute stress are virtually unknown. Here, we assessed these effects in barnacle goslings ( Branta leucopsis ) at a historical coal mine site in the Arctic. For three weeks we led human-imprinted goslings, collected from nests in unpolluted areas, to feed in an abandoned coal mining area, where they were exposed to trace metals. As control we led their siblings to feed on clean grounds. After submitting both groups to three well-established stress tests (group isolation, individual isolation, on-back restraint), control goslings behaved calmer and excreted lower levels of corticosterone metabolites. Thus, legacy contamination may decisively change stress physiology and behaviour in long-lived vertebrates exposed at a young age.
Isabella B. R. Scheiber; Brigitte M. Weiß; Margje E. De Jong; Anna Braun; Nico W. Van Den Brink; Maarten J. J. E. Loonen; Eva Millesi; Jan Komdeur. Stress behaviour and physiology of developing Arctic barnacle goslings ( Branta leucopsis ) is affected by legacy trace contaminants. Proceedings of the Royal Society B: Biological Sciences 2018, 285, 20181866 .
AMA StyleIsabella B. R. Scheiber, Brigitte M. Weiß, Margje E. De Jong, Anna Braun, Nico W. Van Den Brink, Maarten J. J. E. Loonen, Eva Millesi, Jan Komdeur. Stress behaviour and physiology of developing Arctic barnacle goslings ( Branta leucopsis ) is affected by legacy trace contaminants. Proceedings of the Royal Society B: Biological Sciences. 2018; 285 (1893):20181866.
Chicago/Turabian StyleIsabella B. R. Scheiber; Brigitte M. Weiß; Margje E. De Jong; Anna Braun; Nico W. Van Den Brink; Maarten J. J. E. Loonen; Eva Millesi; Jan Komdeur. 2018. "Stress behaviour and physiology of developing Arctic barnacle goslings ( Branta leucopsis ) is affected by legacy trace contaminants." Proceedings of the Royal Society B: Biological Sciences 285, no. 1893: 20181866.
In cooperatively breeding species, helper aid may affect dominant breeders’ investment trade-offs between current and future reproduction. By compensating for the care provided by helpers, breeders can reduce the costs of reproduction and improve chances of survival. Also, helper care can be additive to that of dominants, resulting in higher success of the current brood.However, the influence of helpers on offspring care itself may be the by-product of group size and territory quality. Therefore to make conclusive inferences about causation of additive and compensatory care as a result of helpper serequires disentangling the impact of helping from other factors determining parental investment.In this study, we use 20 years of offspring provisioning data to investigate the effect of helping on breeder and overall offspring provisioning rates in the facultative cooperatively breeding Seychelles warbler (Acrocephalus sechellensis). Our extensive dataset allowed us to effectively control for the effects of living in a larger group and in territories with higher food availability.We show compensatory and additive care in response to helper aid. Helpers lightened the provisioning load of the dominant male and female and increased the total provisioning to the nestlings. This was irrespective of group size or territory quality (food availability).Our results illustrate how multiple benefits of helping behaviour can simultaneously be fundamental to the evolutionary maintenance of cooperative behaviour.
Lotte A. Van Boheemen; Martijn Hammers; Sjouke A. Kingma; David S. Richardson; Terry Burke; Jan Komdeur; Hannah L. Dugdale. Compensatory and additive helper effects in the cooperatively breeding Seychelles warbler (Acrocephalus sechellensis). 2018, 372722 .
AMA StyleLotte A. Van Boheemen, Martijn Hammers, Sjouke A. Kingma, David S. Richardson, Terry Burke, Jan Komdeur, Hannah L. Dugdale. Compensatory and additive helper effects in the cooperatively breeding Seychelles warbler (Acrocephalus sechellensis). . 2018; ():372722.
Chicago/Turabian StyleLotte A. Van Boheemen; Martijn Hammers; Sjouke A. Kingma; David S. Richardson; Terry Burke; Jan Komdeur; Hannah L. Dugdale. 2018. "Compensatory and additive helper effects in the cooperatively breeding Seychelles warbler (Acrocephalus sechellensis)." , no. : 372722.
1.In many cooperatively breeding animals, a combination of ecological constraints and benefits of philopatry favours offspring taking a subordinate position on the natal territory instead of dispersing to breed independently. However, in many species individuals disperse to a subordinate position in a non‐natal group (“subordinate between‐group” dispersal), despite losing the kin‐selected and nepotistic benefits of remaining in the natal group. It is unclear which social, genetic and ecological factors drive between‐group dispersal. 2.We aim to elucidate the adaptive significance of subordinate between‐group dispersal by examining which factors promote such dispersal, whether subordinates gain improved ecological and social conditions by joining a non‐natal group, and whether between‐group dispersal results in increased lifetime reproductive success and survival. 3.Using a long‐term dataset on the cooperatively‐breeding Seychelles warbler (Acrocephalus sechellensis), we investigated 4.how a suite of proximate factors (food availability, group composition, age and sex of focal individuals, population density) promote subordinate between‐group dispersal by comparing such dispersers with subordinates that dispersed to a dominant position or became floaters. We then analysed whether subordinates that moved to a dominant or non‐natal subordinate position, or became floaters, gained improved conditions relative to the natal territory, and compared fitness components between the three dispersal strategies. 5.We show that individuals that joined another group as non‐natal subordinates were mainly female and that, similar to floating, between‐group dispersal was associated with social and demographic factors that constrained dispersal to an independent breeding position. Between‐group dispersal was not driven by improved ecological or social conditions in the new territory and did not result in higher survival. Instead, between‐group dispersing females often became co‐breeders, obtaining maternity in the new territory, and were likely to inherit the territory in the future, leading to higher lifetime reproductive success compared to females that floated. Males never reproduced as subordinates, which may be one explanation why subordinate between‐group dispersal by males is rare. 6.Our results suggest that subordinate between‐group dispersal is used by females to obtain reproductive benefits when options to disperse to an independent breeding position are limited. This provides important insight into the additional strategies that individuals can use to obtain reproductive benefits. This article is protected by copyright. All rights reserved.
Frank Groenewoud; Sjouke A. Kingma; Martijn Hammers; Hannah L. Dugdale; Terry Burke; David S. Richardson; Jan Komdeur. Subordinate females in the cooperatively breeding Seychelles warbler obtain direct benefits by joining unrelated groups. Journal of Animal Ecology 2018, 87, 1251 -1263.
AMA StyleFrank Groenewoud, Sjouke A. Kingma, Martijn Hammers, Hannah L. Dugdale, Terry Burke, David S. Richardson, Jan Komdeur. Subordinate females in the cooperatively breeding Seychelles warbler obtain direct benefits by joining unrelated groups. Journal of Animal Ecology. 2018; 87 (5):1251-1263.
Chicago/Turabian StyleFrank Groenewoud; Sjouke A. Kingma; Martijn Hammers; Hannah L. Dugdale; Terry Burke; David S. Richardson; Jan Komdeur. 2018. "Subordinate females in the cooperatively breeding Seychelles warbler obtain direct benefits by joining unrelated groups." Journal of Animal Ecology 87, no. 5: 1251-1263.
There remains great concern over mercury pollution in the Arctic, though relatively little is known about impacts on biota that inhabit Arctic terrestrial systems. To help address this, the current study was performed with barnacle goslings (Branta leucopsis) from a coal mine-impacted site and a control site near Ny-Ålesund, Spitsbergen (Svalbard). The works focused mainly on mercury, as coal contains trace levels of this element. Total mercury concentrations were quantified in soil and vegetation from the two sites, as well as feces and liver from the goslings. Next, the mercury exposures were related to dopamine 2 (D2)- and NMDA-receptors in the brain, given that mercury is a proven neurotoxicant. Soil and vegetation in the mining area contained mercury levels that were approximately 3- and 2.2-times higher than in the control site. Despite a significant difference between the sites, the soil and vegetation mercury levels where were within ranges found at other Arctic locations. Goslings grazing in the mine-impacted area contained significantly higher hepatic mercury levels than those sampled from the control site. Compared to other species, the hepatic concentrations were relatively low possibly due to dilution of the mercury in growing goslings (growth dilution) and deposition of mercury in the growing feathers. Hepatic mercury concentrations were positively related to D2-neuroreceptor levels but not to NMDA-receptor levels thus suggesting a possible subtle neurological effect. To our knowledge, this is among the first studies on mercury exposure in Arctic terrestrial organisms, and one of the first to document potential subtle neurological responses associated with exposure to low, environmentally relevant mercury levels, which also can be found at other locations in the Arctic. However, as a pilot effort, the results here need to be examined in additional studies that include, for example, lager study designs, different geographic sites and other terrestrial species.
Nico W. Van Den Brink; Isabella B. R. Scheiber; Margje E. de Jong; Anna Braun; Adeline Arini; Niladri Basu; Hans Van Den Berg; Jan Komdeur; Maarten J.J.E. Loonen. Mercury associated neurochemical response in Arctic barnacle goslings (Branta leucopsis). Science of The Total Environment 2018, 624, 1052 -1058.
AMA StyleNico W. Van Den Brink, Isabella B. R. Scheiber, Margje E. de Jong, Anna Braun, Adeline Arini, Niladri Basu, Hans Van Den Berg, Jan Komdeur, Maarten J.J.E. Loonen. Mercury associated neurochemical response in Arctic barnacle goslings (Branta leucopsis). Science of The Total Environment. 2018; 624 ():1052-1058.
Chicago/Turabian StyleNico W. Van Den Brink; Isabella B. R. Scheiber; Margje E. de Jong; Anna Braun; Adeline Arini; Niladri Basu; Hans Van Den Berg; Jan Komdeur; Maarten J.J.E. Loonen. 2018. "Mercury associated neurochemical response in Arctic barnacle goslings (Branta leucopsis)." Science of The Total Environment 624, no. : 1052-1058.
Understanding the ways in which individuals cope with threats, respond to challenges, make use of opportunities and mediate the harmful effects of their surroundings is important for predicting their ability to function in a rapidly changing world. Perhaps one of the most essential drivers of coping behaviour of adults is the environment experienced during their early-life development. Although the study of coping, defined as behaviours displayed in response to environmental challenges, has a long and rich research history in biology, recent literature has repeatedly pointed out that the processes through which coping behaviours develop in individuals are still largely unknown. In this review, we make a move towards integrating ultimate and proximate lines of coping behaviour research. After broadly defining coping behaviours (1), we review why, from an evolutionary perspective, the development of coping has become tightly linked to the early-life environment (2), which relevant developmental processes are most important in creating coping behaviours adjusted to the early-life environment (3), which influences have been shown to impact those developmental processes (4) and what the adaptive significance of intergenerational transmission of coping behaviours is, in the context of behavioural adaptations to a fast changing world (5). Important concepts such as effects of parents, habitat, nutrition, social group and stress are discussed using examples from empirical studies on mammals, fish, birds and other animals. In the discussion, we address important problems that arise when studying the development of coping behaviours and suggest solutions.
M. Rohaa Langenhof; Jan Komdeur. Why and how the early-life environment affects development of coping behaviours. Behavioral Ecology and Sociobiology 2018, 72, 1 -32.
AMA StyleM. Rohaa Langenhof, Jan Komdeur. Why and how the early-life environment affects development of coping behaviours. Behavioral Ecology and Sociobiology. 2018; 72 (3):1-32.
Chicago/Turabian StyleM. Rohaa Langenhof; Jan Komdeur. 2018. "Why and how the early-life environment affects development of coping behaviours." Behavioral Ecology and Sociobiology 72, no. 3: 1-32.
Animals that breed seasonally often use the same territory where they successfully produced young previously. Intra-specific competition may be intense for these high-quality territories, and therefore, natural selection should favour behaviour of territory owners to reduce such competition. Hair-crested drongos, Dicrurus hottentottus, a territory-faithful migratory passerine, dismantle their nests after breeding. As undismantled nests usually remain intact until the next breeding season, we hypothesised that nest dismantling serves the purpose of reducing territory competition from conspecifics that may use the presence of a nest as a cue to select suitable territories in the next year. Here, we provide the first experimental test of this “territory competition hypothesis”. Our results show that successful pairs, who often reuse their territories in the next year, were more likely to dismantle their nests and tended to dismantle faster compared to failed breeding pairs who often moved to another territory in the next year. Strengthened natural nests that were experimentally placed in successful territories attracted prospectors. However, the usurpation rate of those territories in the following year was low and not higher than that of territories where nests were dismantled. Furthermore, returned strengthened-nest owners did not initiate breeding later or produce fewer fledglings suggesting that potential higher territory competition did not affect their reproduction. Altogether, our results only partially support the “territory competition hypothesis”. We suggest that nest dismantling may only be beneficial to drongos in years when territory competition is very intense. Seasonal-breeding animals may face intra-specific competition for high-quality territories. Successful individuals often reuse their territory, but whether they can reduce prospective territory competition through hiding breeding locations (e.g. nests) has rarely been studied. We conducted an experiment to test whether a medium-sized passerine reduces the potential costs of territory competition by destroying their nest after breeding, concealing their selection of territory to other individuals. Territory owners invested more in nest dismantling if they were more likely to reuse the territory. However, they were still able to retain their previous territory and did not have a lower reproductive success if their nest was not dismantled. We suggest that individuals may only benefit from masking public information of breeding habitat selection from conspecifics by dismantling their nest when territory competition is very intense.
Lei Lv; Jianqiang Li; Sjouke A. Kingma; Chang Gao; Yong Wang; Jan Komdeur; Zhengwang Zhang. Do hair-crested drongos reduce prospective territory competition by dismantling their nest after breeding? Behavioral Ecology and Sociobiology 2017, 72, 12 .
AMA StyleLei Lv, Jianqiang Li, Sjouke A. Kingma, Chang Gao, Yong Wang, Jan Komdeur, Zhengwang Zhang. Do hair-crested drongos reduce prospective territory competition by dismantling their nest after breeding? Behavioral Ecology and Sociobiology. 2017; 72 (1):12.
Chicago/Turabian StyleLei Lv; Jianqiang Li; Sjouke A. Kingma; Chang Gao; Yong Wang; Jan Komdeur; Zhengwang Zhang. 2017. "Do hair-crested drongos reduce prospective territory competition by dismantling their nest after breeding?" Behavioral Ecology and Sociobiology 72, no. 1: 12.
In many areas around the Arctic remains and spoil heaps of old mines can be found, which have been abandoned after their heydays. Runoff from tailings of these abandoned mines can directly contaminate the local environment with elevated concentrations of trace metals. Few studies have investigated the possible negative effects of contaminants on Arctic terrestrial animals that use these areas. Trace metals can accumulate in animals and this accumulation has been linked to negative effects on fitness. Both, the hypothalamus-pituitary-adrenal (HPA) axis and/or the immune system have been named as possible underlying causes for these observations. Free-living animals are often exposed to multiple stressors simultaneously, however, and this is often not considered in studies on the effects of contaminants on animal physiology. Here, we performed a study on Spitsbergen (Svalbard) taking both potential effects of trace metal contamination and social stress into account. We investigated experimentally effects of exposure to contaminants from a historic coal mine area on plasma corticosterone levels and on four innate immune parameters (haemolysis, haemagglutination, haptoglobin-like activity and nitric oxide) before and after social isolation in human-raised barnacle goslings (Branta leucopsis). Baseline corticosterone and immune parameters were not affected by mine-exposure. After social isolation, mine goslings tended to show decreased haemagglutination in comparison with control goslings, but we detected no difference in the other measures. Social isolation increased corticosterone and decreased haptoglobin-like activity in all goslings. Immunology and corticosterone levels of barnacle goslings thus seem unaffected, at least on the short term, by Arctic coal mining contamination.
Margje E. De Jong; Isabella B.R. Scheiber; Nico W. Van Den Brink; Anna Braun; Kevin D. Matson; Jan Komdeur; Maarten J.J.E. Loonen. Indices of stress and immune function in Arctic barnacle goslings ( Branta leucopsis ) were impacted by social isolation but not a contaminated grazing environment. Science of The Total Environment 2017, 601-602, 132 -141.
AMA StyleMargje E. De Jong, Isabella B.R. Scheiber, Nico W. Van Den Brink, Anna Braun, Kevin D. Matson, Jan Komdeur, Maarten J.J.E. Loonen. Indices of stress and immune function in Arctic barnacle goslings ( Branta leucopsis ) were impacted by social isolation but not a contaminated grazing environment. Science of The Total Environment. 2017; 601-602 ():132-141.
Chicago/Turabian StyleMargje E. De Jong; Isabella B.R. Scheiber; Nico W. Van Den Brink; Anna Braun; Kevin D. Matson; Jan Komdeur; Maarten J.J.E. Loonen. 2017. "Indices of stress and immune function in Arctic barnacle goslings ( Branta leucopsis ) were impacted by social isolation but not a contaminated grazing environment." Science of The Total Environment 601-602, no. : 132-141.
Cooperative breeding is a form of breeding system where in addition to a core breeding pair, one or more usually non-breeding individuals provide offspring care. Cooperative breeding is widespread in birds, but its origin and maintenance in contemporary populations are debated. Although deviations in adult sex ratio (ASR, the proportion of males in the adult population) have been hypothesized to influence the occurrence of cooperative breeding because of the resulting surplus of one sex and limited availability of breeding partners, this hypothesis has not been tested across a wide range of taxa. By using data from 188 bird species and phylogenetically controlled analyses, we show that cooperatively breeding species have more male-biased ASRs than non-cooperative species. Importantly, ASR predicts helper sex ratio: in species with more male-biased ASR, helper sex ratio is also more male biased. We also show that offspring sex ratios do not predict ASRs, so that the skewed ASRs emerge during the period when individuals aim to obtain a breeding position or later during adulthood. In line with this result, we found that ASR (among both cooperatively and non-cooperatively breeding species) is inversely related to sex bias in dispersal distance, suggesting that the cost of dispersal is more severe for the further-dispersing sex. As females usually disperse further in birds, this explains the generally male-biased ASR, and in combination with benefits of philopatry for males, this probably explains why ASR is more biased in cooperatively breeding species. Taken together, our results suggest that a sex bias in helping in cooperatively breeding species relates to biased ASRs. We propose that this relationship is driven by sex-specific costs and benefits of dispersal and helping, as well as other demographic factors. Future phylogenetic comparative and experimental work is needed to establish how this relationship emerges. This article is part of the themed issue ‘Adult sex ratios and reproductive decisions: a critical re-examination of sex differences in human and animal societies’.
Jan Komdeur; Tamás Székely; Xiaoyan Long; Sjouke Anne Kingma. Adult sex ratios and their implications for cooperative breeding in birds. Philosophical Transactions of the Royal Society B: Biological Sciences 2017, 372, 20160322 .
AMA StyleJan Komdeur, Tamás Székely, Xiaoyan Long, Sjouke Anne Kingma. Adult sex ratios and their implications for cooperative breeding in birds. Philosophical Transactions of the Royal Society B: Biological Sciences. 2017; 372 (1729):20160322.
Chicago/Turabian StyleJan Komdeur; Tamás Székely; Xiaoyan Long; Sjouke Anne Kingma. 2017. "Adult sex ratios and their implications for cooperative breeding in birds." Philosophical Transactions of the Royal Society B: Biological Sciences 372, no. 1729: 20160322.
Kat Bebbington; Lewis G. Spurgin; Eleanor A. Fairfield; Hannah L. Dugdale; Jan Komdeur; Terry Burke; David S. Richardson. Corrigendum. Molecular Ecology 2017, 26, 3585 -3586.
AMA StyleKat Bebbington, Lewis G. Spurgin, Eleanor A. Fairfield, Hannah L. Dugdale, Jan Komdeur, Terry Burke, David S. Richardson. Corrigendum. Molecular Ecology. 2017; 26 (13):3585-3586.
Chicago/Turabian StyleKat Bebbington; Lewis G. Spurgin; Eleanor A. Fairfield; Hannah L. Dugdale; Jan Komdeur; Terry Burke; David S. Richardson. 2017. "Corrigendum." Molecular Ecology 26, no. 13: 3585-3586.
Ownership of non-controllable resources usually has to be maintained by costly defense against competitors. Whether defense and thus ownership pays in terms of fitness depends on its effectiveness in preventing theft. We show that if the owners’ willingness to defend varies in the population and information about it is available to potential thieves then the ability to react to this information and thus avoid being attacked by the owner is selected for. This can lead to a positive evolutionary feedback between cautiousness in intruders and aggressiveness in owners. This feedback can maintain ownership when the actual direct effectiveness of defense in reducing theft is very low or even absent, effectively turning defense into punishment. We conclude that the deterrence effect of defense in many situations could be stronger than that of prevention and that for many real-world scenarios the purpose of defense of resources might be to punish rather than to drive away intruders. Many animals defend resources against conspecifics. Resource defense can usually only evolve if its costs are paid for by foiling attempts at theft. We show that if potential thieves can detect differences in aggressiveness between owners then cautious intruders and aggressive owners coevolve so that in the end even ineffective defense deters thieves and maintains ownership. This result greatly extends the number of situations in which we expect resource defense to evolve and has the potential to unify the concepts of defense and punishment.
Martin Hinsch; Jan Komdeur. Punish the thief—coevolution of defense and cautiousness stabilizes ownership. Behavioral Ecology and Sociobiology 2017, 71, 102 .
AMA StyleMartin Hinsch, Jan Komdeur. Punish the thief—coevolution of defense and cautiousness stabilizes ownership. Behavioral Ecology and Sociobiology. 2017; 71 (7):102.
Chicago/Turabian StyleMartin Hinsch; Jan Komdeur. 2017. "Punish the thief—coevolution of defense and cautiousness stabilizes ownership." Behavioral Ecology and Sociobiology 71, no. 7: 102.
Sjouke A. Kingma; Jan Komdeur; Terry Burke; David S. Richardson. Differential dispersal costs and sex-biased dispersal distance in a cooperatively breeding bird. Behavioral Ecology 2017, 28, 1113 -1121.
AMA StyleSjouke A. Kingma, Jan Komdeur, Terry Burke, David S. Richardson. Differential dispersal costs and sex-biased dispersal distance in a cooperatively breeding bird. Behavioral Ecology. 2017; 28 (4):1113-1121.
Chicago/Turabian StyleSjouke A. Kingma; Jan Komdeur; Terry Burke; David S. Richardson. 2017. "Differential dispersal costs and sex-biased dispersal distance in a cooperatively breeding bird." Behavioral Ecology 28, no. 4: 1113-1121.
Cooperative breeding – in which some sexually mature individuals forgo independent breeding, join a group as subordinate and help to raise the offspring of others – occurs in at least 3% (mammals) and 9% (birds) of vertebrates. Because helping others is costly, this behaviour contradicts the concept of ‘selfish’ natural selection. The intriguing evolutionary paradox of such seemingly altruistic behaviour has, therefore, been the focus of much study aiming to unravelling the evolutionary drivers underlying cooperative breeding. The benefits of group living, costs of dispersal and constraints of limited available independent breeding positions may persuade individuals to delay independent breeding and remain as subordinates within a group. However, it is the range of subsequent benefits (indirect benefits – such as improving reproduction and survival of related individuals or direct benefits – such as gaining breeding experience, benefits of future cooperation with raised recruits or gaining a share in reproduction) that favour the evolution of helping.
Jan Komdeur; David S. Richardson; Martijn Hammers; Cas Eikenaar; Lyanne Brouwer; Sjouke Anne Kingma. The Evolution of Cooperative Breeding in Vertebrates. eLS 2017, 1 -11.
AMA StyleJan Komdeur, David S. Richardson, Martijn Hammers, Cas Eikenaar, Lyanne Brouwer, Sjouke Anne Kingma. The Evolution of Cooperative Breeding in Vertebrates. eLS. 2017; ():1-11.
Chicago/Turabian StyleJan Komdeur; David S. Richardson; Martijn Hammers; Cas Eikenaar; Lyanne Brouwer; Sjouke Anne Kingma. 2017. "The Evolution of Cooperative Breeding in Vertebrates." eLS , no. : 1-11.
1.Oxidative damage, caused by reactive oxygen species during aerobic respiration, is thought to be an important mediator of life-history trade-offs. To mitigate oxidative damage, antioxidant defence mechanisms are deployed, often at the cost of resource allocation to other body functions. Both reduced resource allocation to body functions and direct oxidative damage may decrease individual fitness, through reducing survival and/or reproductive output.2.The oxidative costs of reproduction have gained much attention recently, but few studies have investigated the long-term consequences of oxidative damage on survival and (future) reproductive output under natural conditions.3.Using a wild population of the cooperatively breeding Seychelles warbler (Acrocephalus sechellensis), we tested the prediction that high levels of reactive oxygen species, or high antioxidant investments to avoid oxidative damage, have fitness consequences because they reduce survival and/or reproductive output.4.We found that individuals with higher circulating non-enzymatic antioxidant capacity had a lower probability of surviving until the next year. However, neither current reproductive output, nor future reproductive output in the surviving individuals, was associated with circulating non-enzymatic antioxidant capacity or oxidative damage.5.The negative relationship between antioxidant capacity and survival that we observed concurs with the findings of an extensive comparative study on birds, however the mechanisms underlying this association remain to be resolved.This article is protected by copyright. All rights reserved.
Janske De Crommenacker; Martijn Hammers; Jildou Woude; Marina Louter; Peter Santema; David S. Richardson; Jan Komdeur; Janske Van De Crommenacker; Jildou Van Der Woude; Jildou Der Woude. Oxidative status and fitness components in the Seychelles warbler. Functional Ecology 2017, 31, 1210 -1219.
AMA StyleJanske De Crommenacker, Martijn Hammers, Jildou Woude, Marina Louter, Peter Santema, David S. Richardson, Jan Komdeur, Janske Van De Crommenacker, Jildou Van Der Woude, Jildou Der Woude. Oxidative status and fitness components in the Seychelles warbler. Functional Ecology. 2017; 31 (6):1210-1219.
Chicago/Turabian StyleJanske De Crommenacker; Martijn Hammers; Jildou Woude; Marina Louter; Peter Santema; David S. Richardson; Jan Komdeur; Janske Van De Crommenacker; Jildou Van Der Woude; Jildou Der Woude. 2017. "Oxidative status and fitness components in the Seychelles warbler." Functional Ecology 31, no. 6: 1210-1219.
Theoretical research on evolutionary aspects of territoriality has a long history. Existing studies, however, differ widely in modelling approach and research question. A generalized view on the evolution of territoriality is accordingly still missing. In this review, we show that territorial conflicts can be classified into qualitatively distinct types according to what mode of access to a territory which competitor attempts to gain. We argue that many of the inconsistencies between existing studies can be traced back to the fact that, while using the same terminology, different instances of these types of conflicts have been investigated. We discuss the connections of each type of conflict to existing research within the wider area of animal conflicts. We conclude that a clear conceptual separation of different types of territorial conflicts is helpful but that a more general theory of territoriality has to account for interdependencies between them and that a more mechanistic approach to modelling territoriality is needed.
Martin Hinsch; Jan Komdeur. What do territory owners defend against? Proceedings of the Royal Society B: Biological Sciences 2017, 284, 20162356 .
AMA StyleMartin Hinsch, Jan Komdeur. What do territory owners defend against? Proceedings of the Royal Society B: Biological Sciences. 2017; 284 (1849):20162356.
Chicago/Turabian StyleMartin Hinsch; Jan Komdeur. 2017. "What do territory owners defend against?" Proceedings of the Royal Society B: Biological Sciences 284, no. 1849: 20162356.