No fitness benefits of early molt in a fairy-wren: relaxed sexual selection under genetic monogamy?

Behavioral Ecology, Journal Year: 2017, Volume and Issue: 28(4), P. 1055 - 1067

Published: April 6, 2017

The evolution of male ornamentation has long been the focus sexual selection studies. However, evidence is accumulating that sexually selected traits can also be lost, although process ill-understood. In fairy-wrens (Malurus spp.), early molt into seasonal breeding plumage critical for obtaining extra-pair paternity (EPP), which reaches very high levels in these socially monogamous songbirds. A notable exception purple-crowned fairy-wren, Malurus coronatus, which, like its congeners, breeds cooperatively, but where EPP rare. Nevertheless, males develop a conspicuous at highly variable times. Based on 6 years data collected 137 individuals, we investigated adaptive significance pre-breeding timing as signal under (near) genetic monogamy. Molt varied between and within individuals with age climate: was completed earlier older after wetter years. Despite potential to act quality, fitness benefits costs appear limited: did not correlate 1) likelihood gaining position; 2) female mate preference (EPP/cuckoldry, divorce); 3) reproductive investment (breeding timing, clutch size, number clutches); 4) performance (hatching success, fledging fledgling survival, annual success); 5) survival. predict subordinates would become breeders, breeders molted than subordinates. lack this species might imply relaxed lead trait disappearance.

Language: Английский

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Geographic patterns of song variation in four species of Malurus fairy‐wrens

Journal of Avian Biology, Journal Year: 2017, Volume and Issue: 49(2)

Published: Dec. 1, 2017

Geographic variation in song is widespread among birds, particularly species that learn vocalizations. The relationship between geographic distance and likely related to the degree of isolation populations. To assess this effect on divergence, we examined patterns four Australian fairy‐wrens ( Malurus ), two with suspected histories without. Song all was consistent by distance, allopatric subspecies were more divergent than predicted alone. Each species’ pattern unique, some interspecific could not be explained distance. These results indicate can influenced historical We suggest morphological constraints, environmental influences, sexual selection may contribute observed for each species.

Language: Английский

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Sperm Numbers as a Paternity Guard in a Wild Bird

Cells, Journal Year: 2022, Volume and Issue: 11(2), P. 231 - 231

Published: Jan. 11, 2022

Sperm competition is thought to impose strong selection on males produce competitive ejaculates outcompete rival under mating conditions. Our understanding of how different sperm traits influence fertilization success, however, remains limited, especially in wild populations. Recent literature highlights the importance incorporating multiple ejaculate and pre-copulatory sexually selected analyses aimed at acts traits. However, variation a male's ability gain success may also depend upon range social ecological factors that determine opportunity for events both within outside pair-bond. Here, we test an effect quantity size male reproductive red-back fairy-wren (Malurus melanocephalus) while simultaneously accounting sexual potential socio-ecological correlates success. We found number (i.e., cloacal protuberance volume), but not morphology, was associated with red-backed fairy-wrens. Most notably, large numbers available copulation achieved greater within-pair paternity results suggest use as defensive strategy guard system where there high risk female control copulation. Finally, our work opportunities when examining role determining

Language: Английский

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Drought disrupts year-round breeding readiness in a tropical songbird

Avian Conservation and Ecology, Journal Year: 2022, Volume and Issue: 17(2)

Published: Jan. 1, 2022

Climate change is expected to increase the prevalence and severity of extreme weather events like drought. For many opportunistically breeding tropical bird species, precipitation serves as a primary cue for onset breeding, sustained drought can have major impacts on reproductive fitness. The physiological effects are poorly understood, but understanding responses help resolve mechanisms underlying population demography. We used data collected year-round New Guinea endemic passerine, White-shouldered Fairywren (Malurus alboscapulatus), during years with persistent rainfall 2015–2016 El Niño event assess patterns readiness, body condition, molt. Many males lost their cloacal protuberances, sperm storage organ they typically maintain year-round, period. Body molt, which also occurs in this was higher Using sliding-window statistical model approach, we identified critical window 0–40 days prior capture protuberance volume 8–53 lower associated smaller protuberances greater Plasma androgens were predictive variation male thus potentially mediating transitions between life-history stages response environmental conditions. Female androgens, mass varied photoperiod, longer decreasing day lengths characteristic austral summer increasing molt androgens. Collectively, our results indicate potential photoperiod some stages, whereas reduced apparently not female physiology readiness breed. Improving regulation taxa essential identifying most at risk under changing climate.

Language: Английский

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Asymmetries in reproductive anatomy: insights from promiscuous songbirds

Biological Journal of the Linnean Society, Journal Year: 2019, Volume and Issue: 128(3), P. 569 - 582

Published: June 14, 2019

Abstract Directional asymmetry in gonad size is commonly observed vertebrates and particularly pronounced birds, where the left testis frequently larger than right. The adaptive significance of directional poorly understood, whether it extends beyond testes (i.e. side-correspondent along reproductive tract) has rarely been considered. Using Maluridae, a songbird family exhibiting variation levels sperm competition asymmetry, yet similar ecology life history, we investigated relative roles side-correspondence on male tract at both inter- intraspecific levels. We found some evidence for asymmetry. Additionally, influenced each end tract: species experiencing higher had relatively right more seminal glomerus. Within red-backed fairy-wrens (Malurus melanocephalus), auxiliary males glomerus, contrast to right-bias throughout breeding males. Given that number important competitive fertilization success, our results suggest shapes asymmetries size, with likely functional consequences success.

Language: Английский

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Female and male plumage color is linked to parental quality, pairing, and extrapair mating in a tropical passerine

Behavioral Ecology, Journal Year: 2021, Volume and Issue: 32(3), P. 452 - 463

Published: Jan. 9, 2021

Abstract Sexual selection has been proposed to drive the evolution of elaborate phenotypic traits in males, which often confer success competition or mating. However, many species, both males and females display such traits. Studies examining how acts on sexes are scarce. In this study, we investigated whether plumage ornamentation is sexually selected lovely fairy-wren Malurus amabilis, a cooperatively breeding songbird. We found that female male color was correlated with parental quality but not individual survival. also evidence positive assortative mating based color. Microsatellite analyses paternity indicated high levels extrapair (EPP), 53% offspring (in 58% broods 57% females) resulting from (EP) Female did predict reproductive proportion EP their own nest, less colorful obtained higher EPP when paired more gained overall total (own nest other nests). argue may be under sex-specific selection, highlighting importance looking at studies sexual ornament evolution. The current findings together previous study suggest fairy-wrens appears an honest signal relevant intrasexual intersexual contexts.

Language: Английский

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Behavioral Ecology of Elliot’s Laughingthrush (Trochalopteron (Garrulax) elliotii; Timaliidae): I. Breeding Biology and Social Behavior

Biology Bulletin, Journal Year: 2017, Volume and Issue: 44(9), P. 1090 - 1099

Published: Dec. 1, 2017

Language: Английский

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Female and male plumage colour is linked to parental quality, pairing and extra-pair mating in a tropical passerine

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2020, Volume and Issue: unknown

Published: June 8, 2020

ABSTRACT Sexual selection has been proposed to drive the evolution of elaborate phenotypic traits in males, which often confer success competition or mating. However, many species both males and females display such traits, although studies reporting acting sexes are scarce. In this study, we investigated whether plumage ornamentation is sexually selected female male lovely fairy-wrens Malurus amabilis, a cooperatively breeding songbird. We found that colour was correlated with parental quality but did not incur survival costs. also evidence positive assortative mating based on colour. Microsatellite analyses paternity indicated fairywren high levels extra-pair paternity, 53% offspring resulting from Female predict reproductive proportion its own nest, less colourful obtained higher paternity. argue may be under sex-specific selection, highlighting importance looking at sexual ornament evolution. The current findings together previous suggest appears an honest signal relevant intra inter-sexual contexts.

Language: Английский

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Impacts of mate quality on female intrasexual aggression in two sisterMalurusfairywren species

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Oct. 23, 2023

Abstract In a large and ever-growing number of animal species, it is now appreciated that females use colors as visual signal in range social interactions, including both courtship territorial aggression. Yet, remains unclear whether female color phenotypes and/or aggressive behaviors are correlated with any attributes their mate’s phenotype. For example, we might expect species which males contribute more to parental care or defense have colorful females. On the other hand, within those mated higher quality be than lower males. To begin address these possibilities, conducted preliminary study two sister taxa fairywren (Maluridae) distinct life-history strategies plumage dichromatism: white-shouldered fairywrens ( Malurus alboscapulatus moretoni ) tropical Papua New Guinea, ornamented jointly defend territories year-round, red-backed M. melanocephalus temperate Australia, sexually dichromatic unornamented At between level, predicted would same-sex interactions fairywrens, year-round defense, whereas break-down during non-breeding fairywrens. Further, that, simulated encounters. Between were on average predicted. Within indices male not related aggression (although there was non-significant tendency for heavier mates longer tails). These results point need additional research exploring relationships life history, plumage, wider species.

Language: Английский

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