نتایج جستجو برای: plumage colour

تعداد نتایج: 34775  

Journal: :Indian Journal of Animal Production and Management 2023

Present study was conducted in Bidar district of Karnataka, where 150 eggs were collected from surrounding five different villages. The hatched with 67% hatchability. Chicks reared all standard managemental practices. Twenty healthy female birds plumage colour namely brown, black and yellow tinge selected separated into three pens before the laying stage (at 16th week). first lay observed brown...

Journal: :Proceedings. Biological sciences 2007
Nicola J Nadeau Terry Burke Nicholas I Mundy

The extravagant plumage traits of male birds are a favourite example of sexual selection. However, to date the units that selection is acting upon, the genes themselves have been a 'black box'. Here, we report evidence of change driven by sexual selection at a pigmentation gene locus in the galliform birds. Across species, we find a correlation between the rate of amino acid change (dN/dS) at t...

2012
VICENTE GARCÍA-NAVAS ESPERANZA S. FERRER JUAN JOSÉ SANZ

Carotenoid-based coloration in adult birds has been often regarded as an honest signal of individual quality. However, few studies have demonstrated a link between carotenoid display and the quantity or quality of resources provided to the offspring. The present study investigated the expression of a carotenoid-based ornament, the breast plumage yellowness of the blue tit Cyanistes caeruleus, i...

2017
Yann X C Bourgeois Boris Delahaie Mathieu Gautier Emeline Lhuillier Pierre-Jean G Malé Joris A M Bertrand Josselin Cornuault Kazumasa Wakamatsu Olivier Bouchez Claire Mould Jade Bruxaux Hélène Holota Borja Milá Christophe Thébaud

Understanding the mechanisms responsible for phenotypic diversification within and among species ultimately rests with linking naturally occurring mutations to functionally and ecologically significant traits. Colour polymorphisms are of great interest in this context because discrete colour patterns within a population are often controlled by just a few genes in a common environment. We invest...

Journal: :Proceedings. Biological sciences 2016
J Albert C Uy Elizabeth A Cooper Stephen Cutie Moira R Concannon Jelmer W Poelstra Robert G Moyle Christopher E Filardi

The independent evolution of similar traits across multiple taxa provides some of the most compelling evidence of natural selection. Little is known, however, about the genetic basis of these convergent or parallel traits: are they mediated by identical or different mutations in the same genes, or unique mutations in different genes? Using a combination of candidate gene and reduced representat...

2011
Cas Eikenaar Megan Whitham Jan Komdeur Marco van der Velde Ignacio T. Moore

In most monogamous bird species, circulating testosterone concentration in males is elevated around the social female's fertile period. Variation in elevated testosterone concentrations among males may have a considerable impact on fitness. For example, testosterone implants enhance behaviours important for social and extra-pair mate choice. However, little is known about the relationship betwe...

Journal: :Journal of evolutionary biology 2003
B Tschirren P S Fitze H Richner

Many vertebrates use carotenoid-based signals in social or sexual interactions. Honest signalling via carotenoids implies some limitation of carotenoid-based colour expression among phenotypes in the wild, and at least five limiting proximate mechanisms have been hypothesized. Limitation may arise by carotenoid-availability, genetic constraints, body condition, parasites, or detrimental effects...

Journal: :Journal of evolutionary biology 2003
P Galeotti D Rubolini P O Dunn M Fasola

We studied polymorphism in all species of birds that are presently known to show intraspecific variation in plumage colour. At least three main mechanisms have been put forward to explain the maintenance of polymorphism: apostatic, disruptive and sexual selection. All of them make partly different predictions. Our aims were to investigate evolutionary causes and adaptive functions of colour pol...

Journal: :Ornis Hungarica 2023

Abstract Leucism is a colour anomaly defined by lack of pigmentation, which may be partial or full in any individual. Although genetic and environmental factors contribute to high incidence plumage aberrations wild birds, the true these populations has been studied very less. The present report describes an instance leucism Greater Coucal (Centropus sinensis) from Chhattisgarh, India. This aber...

Journal: :Proceedings. Biological sciences 2009
Nicolas J Rawlence Jamie R Wood Kyle N Armstrong Alan Cooper

Feathers are known to contain amplifiable DNA at their base (calamus) and have provided an important genetic source from museum specimens. However, feathers in subfossil deposits generally only preserve the upper shaft and feather 'vane' which are thought to be unsuitable for DNA analysis. We analyse subfossil moa feathers from Holocene New Zealand rockshelter sites and demonstrate that both an...

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