Mating strategies, parental investment and mutual ornamentation in Iberian Rock Sparrows (Petronia petronia)

Relatively few bird species show complex social mating systems whose preponderance in a population is likely to affect the patterns of parental care observed there. In turn, parental investment is likely to be related to the expression of certain ornaments, which may reveal information on the bearer’s individual quality. Here we address both issues in a species characterised by several forms of parental care (both biparental and uniparental care) and in which both sexes possess a yellow breast patch, the rock sparrow (Petronia petronia). In our population, males contributed more to the care of the young in comparison with other populations. Social monogamy was the most frequent mating pattern and the percentage of cases of female (or male) brood desertion was lower with respect to that reported in previous studies, suggesting a flexible behaviour of this species to deal with different social environments. Birds did not pair assortatively with respect to the size of the yellow breast patch and we found no significant relationship between this trait and the frequency with which parents provisioned their chicks. However, we observed a positive relationship between male yellow patch size and nestling tarsus length, which suggests that more ornamented males are better parents. Males, but not females, differentially allocated parental investment in response to female ornamentation, although the benefits that males may gain from choosing more attractive females remain unidentified. Our results on paternal care investment along with previous studies on this species, reinforcing the view that the rock sparrow constitutes a good model to study sexual conflict over parental care under different social environments.

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Evolution of parental incubation behaviour in dinosaurs cannot be inferred from clutch mass in birds

Biology Letters ◽

10.1098/rsbl.2013.0036 ◽

2013 ◽

Vol 9 (4) ◽

pp. 20130036 ◽

Cited By ~ 14

Author(s):

Geoffrey F. Birchard ◽

Marcello Ruta ◽

D. Charles Deeming

Keyword(s):

Parental Care ◽

Clutch Size ◽

Paternal Care ◽

Bird Species ◽

Scaling Analysis ◽

Theropod Dinosaurs ◽

Incubation Behaviour ◽

Allometric Analysis ◽

Clutch Mass

A recent study proposed that incubation behaviour (i.e. type of parental care) in theropod dinosaurs can be inferred from an allometric analysis of clutch volume in extant birds. However, the study in question failed to account for factors known to affect egg and clutch size in living bird species. A new scaling analysis of avian clutch mass demonstrates that type of parental care cannot be distinguished by conventional allometry because of the confounding effects of phylogeny and hatchling maturity. Precociality of young but not paternal care in the theropod ancestors of birds is consistent with the available data.

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Parental care and brood division in a songbird, the black redstart

Behaviour ◽

10.1163/156853905774831828 ◽

2005 ◽

Vol 142 (11-12) ◽

pp. 1495-1514 ◽

Cited By ~ 13

Author(s):

Tudor I. Draganoiu ◽

Laurent Nagle ◽

Raphael Musseau ◽

Michel Kreutzer

Keyword(s):

Parental Care ◽

Sexual Conflict ◽

Parental Investment ◽

Negative Relationship ◽

Feeding Rates ◽

Close Link ◽

Brood Division ◽

Black Redstart ◽

Phoenicurus Ochruros ◽

Brood Desertion

AbstractSexual conflict over parental care can be mediated through differences in male and female overall feeding rates, brood division or both. At present, it is not clear whether post-fledging brood division occurs due to sexual conflict over parental investment or is due to bi-parental cooperation, e.g. increase offspring fitness. We provide evidence suggesting that brood division in the black redstart, Phoenicurus ochruros is due to sexual conflict. Males and females had similar feeding contributions during the nestling stage, which is common for most passerine species. After fledging, each parent showed long-term feeding preferences for particular chicks within the brood. In most cases (74%; 17/23) both parents provided care but males tended to feed less fledglings than females did and in about a quarter of cases (26%; 6/23) females fed the whole brood by themselves. The relative amount of male to female post-fledging feedings showed a significant negative relationship with the proportion of fledglings cared for exclusively by the male. These results suggest (1) a close link between the amount of parental care and brood division; (2) sexual conflict can be mediated through brood division; (3) female redstarts appear to loose this conflict more often than male redstarts, with in the extreme cases males showing post-fledging brood desertion. A literature review shows brood division to occur in at least a dozen of songbird species but male black redstarts have the lowest relative post-fledging parental investment, expressed either as feeding rates or number of chicks in care.

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Why is mutual mate choice not the norm? Operational sex ratios, sex roles and the evolution of sexually dimorphic and monomorphic signalling

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2001.0926 ◽

2002 ◽

Vol 357 (1419) ◽

pp. 319-330 ◽

Cited By ~ 225

Author(s):

H. Kokko ◽

R. A. Johnstone

Keyword(s):

Mate Choice ◽

Parental Care ◽

Parental Investment ◽

Sex Roles ◽

Mating Strategies ◽

Operational Sex Ratio ◽

Encounter Rate ◽

Theoretic Model ◽

Biparental Care ◽

Mutual Mate Choice

Biases in the operational sex ratio (OSR) are seen as the fundamental reason behind differential competition for mates in the two sexes, and as a strong determinant behind differences in choosiness. This view has been challenged by Kokko and Monaghan, who argue that sex–specific parental investment, mortalities, mate–encounter rates and quality variation determine the mating system in a way that is not reducible to the OSR. We develop a game–theoretic model of choosiness, signalling and parental care, to examine (i) whether the results of Kokko and Monaghan remain robust when its simplifying assumptions are relaxed, (ii) how parental care coevolves with mating strategies and the OSR and (iii) why mutual mate choice is observed relatively rarely even when both sexes vary in quality. We find qualitative agreement with the simpler approach: parental investment is the primary determinant of sex roles instead of the OSR, and factors promoting choosiness are high species–specific mate–encounter rate, high sex–specific mate–encounter rate, high cost of breeding (parental investment), low cost of mate searching and highly variable quality of the opposite sex. The coevolution of parental care and mating strategies hinders mutual mate choice if one parent can compensate for reduced care by the other, but promotes it if offspring survival depends greatly on biparental care. We argue that the relative rarity of mutual mate choice is not due to biases in the OSR. Instead, we describe processes by which sexual strategies tend to diverge. This divergence is prevented, and mutual mate choice maintained, if synergistic benefits of biparental care render parental investment both high and not too different in the two sexes.

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Sex roles and the evolution of parental care specialization

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2019.1312 ◽

2019 ◽

Vol 286 (1909) ◽

pp. 20191312 ◽

Cited By ~ 5

Author(s):

Jonathan M. Henshaw ◽

Lutz Fromhage ◽

Adam G. Jones

Keyword(s):

Parental Care ◽

Parental Investment ◽

Sex Roles ◽

Sex Role ◽

Relative Size ◽

Female Competition ◽

Male Mating ◽

Recent Theory ◽

Mating Competition ◽

Uniparental Care

Males and females are defined by the relative size of their gametes (anisogamy), but secondary sexual dimorphism in fertilization, parental investment and mating competition is widespread and often remarkably stable over evolutionary timescales. Recent theory has clarified the causal connections between anisogamy and the most prevalent differences between the sexes, but deviations from these patterns remain poorly understood. Here, we study how sex differences in parental investment and mating competition coevolve with parental care specialization. Parental investment often consists of two or more distinct activities (e.g. provisioning and defence) and parents may care more efficiently by specializing in a subset of these activities. Our model predicts that efficient care specialization broadens the conditions under which biparental investment can evolve in lineages that historically had uniparental care. Major transitions in sex roles (e.g. from female-biased care with strong male mating competition to male-biased care with strong female competition) can arise following ecologically induced changes in the costs or benefits of different care types, or in the sex ratio at maturation. Our model provides a clear evolutionary mechanism for sex-role transitions, but also predicts that such transitions should be rare. It consequently contributes towards explaining widespread phylogenetic inertia in parenting and mating systems.

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Actuarial senescence in a dimorphic bird: different rates of ageing in morphs with discrete reproductive strategies

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2018.2053 ◽

2018 ◽

Vol 285 (1892) ◽

pp. 20182053 ◽

Cited By ~ 2

Author(s):

Melissa L. Grunst ◽

Andrea S. Grunst ◽

Vincent A. Formica ◽

Marisa L. Korody ◽

Adam M. Betuel ◽

...

Keyword(s):

Parental Care ◽

Parental Investment ◽

Parental Support ◽

Alternative Hypothesis ◽

Mating Strategies ◽

Competitive Strategies ◽

Zonotrichia Albicollis ◽

Sexual Competition ◽

Senescence Rate ◽

Genetically Determined

It is often hypothesized that intra-sexual competition accelerates actuarial senescence, or the increase in mortality rates with age. However, an alternative hypothesis is that parental investment is more important to determining senescence rates. We used a unique model system, the white-throated sparrow ( Zonotrichia albicollis ), to study variation in actuarial senescence. In this species, genetically determined morphs display discrete mating strategies and disassortative pairing, providing an excellent opportunity to test the predictions of the above hypotheses. Compared to tan-striped males, white-striped males are more polygynous and aggressive, and less parental. Tan-striped females receive less parental support, and invest more into parental care than white-striped females, which are also more aggressive. Thus, higher senescence rates in males and white-striped birds would support the intra-sexual competition hypothesis, whereas higher senescence rates in females and tan-striped birds would support the parental investment hypothesis. White-striped males showed the lowest rate of actuarial senescence. Tan-striped females had the highest senescence rate, and tan-striped males and white-striped females showed intermediate, relatively equal rates. Thus, results were inconsistent with sexual selection and competitive strategies increasing senescence rates, and instead indicate that senescence may be accelerated by female-biased parental care, and lessened by sharing of parental duties.

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How sex-biased dispersal affects conflict over parental investment

10.1101/026732 ◽

2015 ◽

Author(s):

Bram Kuijper ◽

Rufus A Johnstone

Keyword(s):

Sex Differences ◽

Parental Care ◽

Parental Investment ◽

Population Level ◽

Uniparental Care ◽

The Family ◽

The Face ◽

Classical Models ◽

Limited Dispersal ◽

The Impact

Abstract Existing models of parental investment have mainly focused on interactions at the level of the family, and have paid much less attention to the impact of population-level processes. Here we extend classical models of parental care to assess the impact of population structure and limited dispersal. We find that sex-differences in dispersal substantially affect the amount of care provided by each parent, with the more philopatric sex providing the majority of the care to young. This effect is most pronounced in highly viscous populations: in such cases, when classical models would predict stable biparental care, inclusion of a modest sex difference in dispersal leads to uniparental care by the philopatric sex. In addition, mating skew also affects sex-differences in parental investment, with the more numerous sex providing most of the care. However, the effect of mating skew only holds when parents care for their own offspring. When individuals breed communally, we recover the previous finding that the more philopatric sex provides most of the care, even when it is the rare sex. Finally, we show that sex-differences in dispersal can mask the existence of sex-specific costs of care, because the philopatric sex may provide most of the care even in the face of far higher mortality costs relative to the dispersing sex. We conclude that sex-biased dispersal is likely to be an important, yet currently overlooked driver of sex-differences in parental care.

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The evolution of avian parental care

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2001.0923 ◽

2002 ◽

Vol 357 (1419) ◽

pp. 241-250 ◽

Cited By ~ 53

Author(s):

N. T. Burley ◽

K. Johnson

Keyword(s):

Parental Care ◽

Parental Investment ◽

Life History Traits ◽

Stage Iv ◽

Young Female ◽

Cost Of Care ◽

Biparental Care ◽

Social Monogamy ◽

Care Giving ◽

Initial Cost

A stage model traces key behavioural tactics and life–history traits that are involved in the transition from promiscuity with no parental care, the mating system that typifies reptiles, to that typical of most birds, social monogamy with biparental care. In stage I, females assumed increasing parental investment in precocial young, female choice of mates increased, female–biased mating dispersal evolved and population sex ratios became male biased. In stage II, consortships between mating partners allowed males to attract rare social mates, provided a mechanism for paternity assessment and increased female ability to assess mate quality. In stage III, relative female scarcity enabled females to demand parental investment contributions from males having some paternity certainty. This innovation was facilitated by the nature of avian parental care; i.e. most care–giving activities can be adopted in small units. Moreover, the initial cost of care giving to males was small compared with its benefit to females. Males, however, tended to decline to assume non–partitionable, risky, or relatively costly parental activities. In stage IV, altriciality coevolved with increasing biparental care, resulting in social monogamy. Approaches for testing behavioural hypotheses are suggested.

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Experimentally increased costs of parental care are shunted to offspring in species with extended care

10.32942/osf.io/y8wx4 ◽

2019 ◽

Author(s):

Gretchen F. Wagner ◽

Emeline Mourocq ◽

Michael Griesser

Keyword(s):

Life History ◽

Parental Care ◽

Total Duration ◽

Bird Species ◽

Life History Strategy ◽

Experimental Treatment ◽

Cost Of Care ◽

Adult Survival ◽

Supporting Evidence ◽

Trade Offs

Biparental care systems are a valuable model to examine conflict, cooperation, and coordination between unrelated individuals, as the product of the interactions between the parents influences the fitness of both individuals. A common experimental technique for testing coordinated responses to changes in the costs of parental care is to temporarily handicap one parent, inducing a higher cost of providing care. However, dissimilarity in experimental designs of these studies has hindered interspecific comparisons of the patterns of cost distribution between parents and offspring. Here we apply a comparative experimental approach by handicapping a parent at nests of five bird species using the same experimental treatment. In some species, a decrease in care by a handicapped parent was compensated by its partner, while in others the increased costs of care were shunted to the offspring. Parental responses to an increased cost of care primarily depended on the total duration of care that offspring require. However, life history pace (i.e., adult survival and fecundity) did not influence parental decisions when faced with a higher cost of caring. Our study highlights that a greater attention to intergenerational trade-offs is warranted, particularly in species with a large burden of parental care. Moreover, we demonstrate that parental care decisions may be weighed more against physiological workload constraints than against future prospects of reproduction, supporting evidence that avian species may devote comparable amounts of energy into survival, regardless of life history strategy.

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