نتایج جستجو برای: plumage colour
تعداد نتایج: 34775 فیلتر نتایج به سال:
Abstract Semen quality and fertility in crossbreeding between white plumage black indigenous turkey hens using artificial insemination were investigated. Eighty-two healthy turkeys, comprising 72 (Thirty-two forty white) 10 toms (five five used. The turkeys grouped into four treatments based on the breeding plans: T1 (White X White hens), T2 (Black Black T3 hens) T4 hens). was harvested from to...
Juveniles of many avian species possess a spotted or mottled body plumage that is visually distinct from the plumage of adults. In other species, however, juveniles fledge with a body plumage that is just a pale representation of adult female plumage. The reasons for this variation are poorly understood. Several hypotheses concerning social (parent–offspring, adult–juvenile, juvenile–juvenile),...
Over the past five years, U.S. breeding colonies of the endangered California Least Tern (Sterna albifrons browni •) have been closely monitored throughout the nesting season (Atwood et al., 1977). One result of this close scrutiny has been the observation each year of a small number of birds in prebreeding or subadult plumages (in this discussion, the term subadult is used to represent any alt...
Structural colors result from the physical interaction of light with organic materials of differing refractive indexes organized at nanoscale dimensions to produce significant interference effects. Because color properties emerge from these finely organized nanostructures, the production of structural coloration could respond to environmental factors and be developmentally more plastic than exp...
Brilliant plumage is typical of male birds, reflecting differential enhancement of male traits when females are the limiting sex. Brighter females are thought to evolve exclusively in response to sex role reversal. The striking reversed plumage dichromatism of Eclectus roratus parrots does not fit this pattern. We quantify plumage color in this species and show that very different selection pre...
Conspicuous ornamentation has been linked to immunological and physiological condition in males of many species. In species where both sexes are ornamented, it is unclear whether the signal content of ornaments differs between males and females. We examined the immunological and physiological correlates of carotenoid-based bill and plumage ornamentation in American goldfinches Spinus tristis, a...
Conspicuous ornamentation has been linked to immunological and physiological condition in males of many species. In species where both sexes are ornamented, it is unclear whether the signal content of ornaments differs between males and females. We examined the immunological and physiological correlates of carotenoid-based bill and plumage ornamentation in American goldfinches Spinus tristis, a...
The interactions between the effects of three plumage color mutations taken two-by-two (sex-linked recessive roux, autosomal recessive lavender, and autosomal dominant beige) were studied in Japanese quail by producing a total of 121 F(1) and 1118 F(2) quail from the three pure stocks. Three new plumage colors were obtained in F(2) quail: roux-diluted beige, cream, and lavender-diluted beige. T...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید