Sex differences in helping effort reveal the effect of future reproduction on cooperative behaviour in birds

The evolution of helping behaviour in species that breed cooperatively in family groups is typically attributed to kin selection alone. However, in many species, helpers go on to inherit breeding positions in their natal groups, but the extent to which this contributes to selection for helping is unclear as the future reproductive success of helpers is often unknown. To quantify the role of future reproduction in the evolution of helping, we compared the helping effort of female and male retained offspring across cooperative birds. The kin selected benefits of helping are equivalent between female and male helpers—they are equally related to the younger siblings they help raise—but the future reproductive benefits of helping differ because of sex differences in the likelihood of breeding in the natal group. We found that the sex which is more likely to breed in its natal group invests more in helping, suggesting that in addition to kin selection, helping in family groups is shaped by future reproduction.

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Carotenoid-based plumage colouration in red bishops (Euplectes orix) — signalling presence rather than quality?

Behaviour ◽

10.1163/000579511x608693 ◽

2011 ◽

Vol 148 (11-13) ◽

pp. 1372-1392 ◽

Cited By ~ 3

Author(s):

Alice U. Edler ◽

Thomas W.P. Friedl

Keyword(s):

Reproductive Success ◽

Parasite Load ◽

Blood Parasite ◽

Male Reproductive Success ◽

Sexually Dimorphic ◽

Male Quality ◽

Plumage Colouration ◽

Selection For ◽

Breeding Plumage

AbstractThe role of bright plumage colouration for female choice has been the focus of research in sexual selection for many years, with several studies showing that females prefer the most elaborately ornamented males, which are often also the highest quality individuals. Here, we analysed the associations between reproductive performance and plumage, body condition and blood parasite load in the red bishop (Euplectes orix), a sexually dimorphic and polygynous weaverbird species, where males in a carotenoid-based orange-to-red breeding plumage defend territories and build many nests to which they try to attract females. Male reproductive success in terms of number of nests accepted was mainly determined by the number of nests built, but was also positively related to blood parasite load, while we found no influence of plumage characteristics. Together with previously obtained data, our results indicate that plumage characteristics in the red bishop do not affect male reproductive success and are generally not suitable to reliably indicate male quality. We suggest that the primary function of the brilliant orange-scarlet breeding plumage might be presence signalling in terms of increasing conspicuousness of breeding males to females searching for mates.

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Beyond buying time: the role of plasticity in phenotypic adaptation to rapid environmental change

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2018.0174 ◽

2019 ◽

Vol 374 (1768) ◽

pp. 20180174 ◽

Cited By ~ 76

Author(s):

Rebecca J. Fox ◽

Jennifer M. Donelson ◽

Celia Schunter ◽

Timothy Ravasi ◽

Juan D. Gaitán-Espitia

Keyword(s):

Phenotypic Plasticity ◽

Environmental Change ◽

Environmental Conditions ◽

Theme Issue ◽

The Future ◽

Selection For ◽

The Individual ◽

Plastic Responses ◽

Rapid Environmental Change

How populations and species respond to modified environmental conditions is critical to their persistence both now and into the future, particularly given the increasing pace of environmental change. The process of adaptation to novel environmental conditions can occur via two mechanisms: (1) the expression of phenotypic plasticity (the ability of one genotype to express varying phenotypes when exposed to different environmental conditions), and (2) evolution via selection for particular phenotypes, resulting in the modification of genetic variation in the population. Plasticity, because it acts at the level of the individual, is often hailed as a rapid-response mechanism that will enable organisms to adapt and survive in our rapidly changing world. But plasticity can also retard adaptation by shifting the distribution of phenotypes in the population, shielding it from natural selection. In addition to which, not all plastic responses are adaptive—now well-documented in cases of ecological traps. In this theme issue, we aim to present a considered view of plasticity and the role it could play in facilitating or hindering adaption to environmental change. This introduction provides a re-examination of our current understanding of the role of phenotypic plasticity in adaptation and sets the theme issue's contributions in their broader context. Four key themes emerge: the need to measure plasticity across both space and time; the importance of the past in predicting the future; the importance of the link between plasticity and sexual selection; and the need to understand more about the nature of selection on plasticity itself. We conclude by advocating the need for cross-disciplinary collaborations to settle the question of whether plasticity will promote or retard species' rates of adaptation to ever-more stressful environmental conditions. This article is part of the theme issue ‘The role of plasticity in phenotypic adaptation to rapid environmental change’.

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Are flies kind to kin? The role of intra- and inter-sexual relatedness in mediating reproductive conflict

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2015.1991 ◽

2015 ◽

Vol 282 (1821) ◽

pp. 20151991 ◽

Cited By ~ 24

Author(s):

Emily S. Martin ◽

Tristan A. F. Long

Keyword(s):

Sexual Conflict ◽

Kin Selection ◽

Alternative Explanation ◽

Potential Role ◽

Inclusive Fitness ◽

Empirical Support ◽

Cooperative Behaviour ◽

Males And Females ◽

Individual Success

As individual success often comes at the expense of others, interactions between the members of a species are frequently antagonistic, especially in the context of reproduction. In theory, this conflict may be reduced in magnitude when kin interact, as cooperative behaviour between relatives can result in increased inclusive fitness. Recent tests of the potential role of cooperative behaviour between brothers in Drosophila melanogaster have proved to be both exciting and controversial. We set out to replicate these experiments, which have profound implications for the study of kin selection and sexual conflict, and to expand upon them by also examining the potential role of kinship between males and females in reproductive interactions. While we did observe reduced fighting and courtship effort between competing brothers, contrary to previous studies we did not detect any fitness benefit to females as a result of the modification of male antagonistic behaviours. Furthermore, we did not observe any differential treatment of females by their brothers, as would be expected if the intensity of sexual conflict was mediated by kin selection. In the light of these results, we propose an alternative explanation for observed differences in male–male conflict and provide preliminary empirical support for this hypothesis.

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Kin selection, not indirect reciprocity, explains helping those who help others in ‘image scoring’

10.1101/2019.12.11.872937 ◽

2019 ◽

Author(s):

Gilbert Roberts

Keyword(s):

Kin Selection ◽

Scoring Systems ◽

Indirect Reciprocity ◽

Helping Others ◽

Helping Behaviour ◽

Evolutionary Simulation ◽

Indirect Fitness ◽

The Individual ◽

To Receive

AbstractIndirect reciprocity is often considered key to human sociality. It occurs when helping others results in an increase in reciprocal benefits from third parties. Indirect reciprocity has been proposed to operate through ‘image scoring’ mechanisms, whereby those who have been seen to help are more likely to receive help. Here I show that helping those who help others in image scoring models is not a mechanism of indirect reciprocity but is instead due to kin selection. Image scoring strategies are not individually adaptive because they base the decision to help upon whether a recipient has previously helped others, rather than upon whether helping would maximize their own return. Using analysis supported by evolutionary simulation, I show that helping can be favoured in image scoring systems without reciprocation, hence image scoring systems are not models of indirect reciprocity at all. Further, I use simulation of image scoring in meta-population models to illustrate how helping is a function of relatedness. I show that relatedness explains cooperation in image scoring (and associated) systems because helpers get indirect fitness benefits from helping others that share their strategy. A strategy of helping those who help others helps other copies of itself. In this way, helping behaviour ceases to be costly, and is in fact beneficial to the strategy, though not to the individual. Thus, despite some recent doubts about the usefulness of Hamilton’s rule, image scoring systems demonstrate the role of relatedness in driving cooperation.

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Challenges of Fear Conditioning Research in the Age of RDoC

Zeitschrift für Psychologie ◽

10.1027/2151-2604/a000303 ◽

2017 ◽

Vol 225 (3) ◽

pp. 189-199 ◽

Cited By ~ 5

Author(s):

Tina B. Lonsdorf ◽

Jan Richter

Keyword(s):

Fear Conditioning ◽

Clinical Diagnosis ◽

Research Domain Criteria ◽

Major Focus ◽

The Future ◽

Definition Of ◽

Methodological Considerations ◽

Research Domain

Abstract. As the criticism of the definition of the phenotype (i.e., clinical diagnosis) represents the major focus of the Research Domain Criteria (RDoC) initiative, it is somewhat surprising that discussions have not yet focused more on specific conceptual and procedural considerations of the suggested RDoC constructs, sub-constructs, and associated paradigms. We argue that we need more precise thinking as well as a conceptual and methodological discussion of RDoC domains and constructs, their interrelationships as well as their experimental operationalization and nomenclature. The present work is intended to start such a debate using fear conditioning as an example. Thereby, we aim to provide thought-provoking impulses on the role of fear conditioning in the age of RDoC as well as conceptual and methodological considerations and suggestions to guide RDoC-based fear conditioning research in the future.

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