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1.
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On the basis of reflection measurements and colorimetric characteristics, the parameters of wing coloration for six European species of the genus Colias are established. The specificity of individual species and differentiation between the species according to the quantitative indices for wing coloration are revealed.  相似文献   

3.
Phenotypic adaptation in terms of background color matching to the local habitat is an important mechanism for survival in prey species. Thus, intraspecific variation in cryptic coloration is expected among localities with dissimilar habitat features (e.g., soil, vegetation). Yellow‐bellied toads (Bombina variegata) display a dark dorsal coloration that varies between populations, assumed to convey crypsis. In this study, we explored I) geographic variation in dorsal coloration and II) coloration plasticity in B. variegata from three localities differing in substrate coloration. Using avian visual modeling, we found that the brightness contrasts of the cryptic dorsa were significantly lower on the local substrates than substrates of other localities. In experiments, individuals from one population were able to quickly change the dorsal coloration to match a lighter substrate. We conclude that the environment mediates an adaptation in cryptic dorsal coloration. We suggest further studies to test the mechanisms by which the color change occurs and explore the adaptive potential of coloration plasticity on substrates of varying brightness in B. variegata and other species.  相似文献   

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Females of the fighting fish Betta splendens have been shown to associate with other B. splendens females in a manner reminiscent of shoaling behavior. Since body coloration varies dramatically in this species, and since body coloration has been shown to affect shoalmate choice in other species of fish, we examined the influence of body coloration on association preferences in female B. splendens. In dichotomous choice tests, B. splendens females spent more time swimming near groups of females (regardless of coloration) than swimming near an empty chamber, and chose to swim near fish of similar coloration to their own when choosing between two distinctly colored groups of females. When examining the interplay between body coloration and group size, focal fish spent more time swimming near larger groups (N = 5) of similarly colored fish than swimming near an individual female of similar coloration. However, focal fish showed no preference when presented with an individual female of similar coloration and a larger group of females of dissimilar coloration. These results suggest that association choices in B. splendens females are strongly affected by both body coloration and by group size.  相似文献   

6.
In animal species that have morphological polymorphisms maintained by unique or divergent selection pressures, understanding the preservation of shared traits is important for identifying the factors that are influencing overall evolutionary processes. In the Eastern tiger swallowtail butterfly, Papilio glaucus, females are dimorphic. One morph (‘dark-morph’) is mostly black and mimics the toxic pipevine swallowtail, Battus philenor. These females have large amounts of blue coloration on the dorsal hind wings that enhances their mimetic resemblance. Conversely, the alternate female type (‘yellow-morph’) is similar to males in coloration with the exception of extensive dorsal blue coloration, comparable to dark-morph females. Such coloration is almost completely absent in males. We examined dorsal blue coloration in P. glaucus to determine if mimetic resemblance in dark morphs is predominantly responsible for the maintenance of dorsal blue color in both female types, or whether mate recognition and/or sexual selection by males has a stronger influence on this trait. We measured the relative amount and variance of dorsal and ventral blue coloration in females of both color morphs, as well as males. We also compared these measurements to similar ones taken in the sister species, P. canadensis (which does not exhibit female dimorphism). Lastly, we investigated mate recognition and preferences of wild males. Our results suggest that mimetic resemblance may be more important than sexual selection for sustaining dorsal blue coloration in dark-morph females and that yellow-morphs could have elevated levels of blue due to currently unknown genetic associations. Although trait correlation between sexes is common, intrasexual trait correlation in a sex-limited, polymorphic species has not been frequently observed.  相似文献   

7.
New species of the genera Gymnothorax (fam. Muraenidae) and Parapercis (fam. Mugiloididae) are described from coastal waters of central Vietnam. G. emmae sp. n. is a common species all along the coast from the Van Phong Bay to the Phan Thiet Bay and differs from other species of this genus in characters of coloration, dentition, and the vertebral formula. P. bicoloripes sp. n. is common in the Phan Thiet Bay and is also know from one specimen from the Nha Trang Bay; from other species of the genus, it differs in coloration and meristic characters.  相似文献   

8.
Red coloration is a conspicuous feature of many visual signals and can function to attract or deter its viewers. Among fishes, red is associated with specialized nuptial, territorial and aposematic (warning) displays. Both sexes of the firemouth cichlid fish Thorichthys meeki develop red ventral coloration at sexual maturity, along with temporally variable black (melanic) elements. Isolated adult firemouth cichlids sequentially presented paired dummy and paired video conspecifics, both with and without red ventral coloration. Subjects interacted more with red-containing stimuli, but with a significant interaction: dummy presentations revealed a strong, positive red bias that video presentations did not. In addition, the melanic color pattern displayed by subjects at the initiation of each trial had a significant effect on subject responsiveness. These results reveal the potential for between-subject differences and experimental design parameters to interact critically in the study of animal color patterns.  相似文献   

9.
Summary Various polyclonal and monoclonal antibodies to keratins were used to stain different human muscle tissues by paired immunofluorescence and the unlabelled antibody peroxidase-anti-peroxidase method. In the myocardium, distinct coloration of the intercalated discs was produced by two polyclonal reagents to human epidermal keratins but not by two monoclonal antibodies to cytokeratins from pig renal tubular cells. In the myometrium — mainly in the middle layer of the uterine wall — cytoplasmic coloration of a varying fraction of the smooth muscle bundles was produced, especially by one of the polyclonal and by both monoclonal reagents. The staining was often confined to the perinuclear region. The keratin-positive myometrial cells usually coexpressed vimentin and actin in various proportions. These findings indicated that intermediate filaments of the keratin type, or antigenically similar elements, are not restricted to cells of epithelial origin. Other types of muscle cells did not react with keratin antibodies, but keratin-positive macrophages were occasionally found in tongue musculature and in inflamed epicardium. Altogether, our observations emphasize that keratin reactivity cannot be considered specific for epithelial (or mesothelial) cells without reservation.Supported by the Norwegian Cancer Society, Jahre's Fund, and the Norwegian Research Council for Science and the Humanities  相似文献   

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Many animals use carotenoid pigments to produce yellow, orange, and red coloration. In birds, at least 10 carotenoid compounds have been documented in red feathers; most of these are produced through metabolic modification of dietary precursor compounds. However, it is poorly understood how lineages have evolved the biochemical mechanisms for producing red coloration. We used high‐performance liquid chromatography to identify the carotenoid compounds present in feathers from 15 species across two clades of blackbirds (the meadowlarks and allies, and the caciques and oropendolas; Icteridae), and mapped their presence or absence on a phylogeny. We found that the red plumage found in meadowlarks includes different carotenoid compounds than the red plumage found in caciques, indicating that these gains of red color are convergent. In contrast, we found that red coloration in two closely related lineages of caciques evolved twice by what appear to be similar biochemical mechanisms. The C4‐oxygenation of dietary carotenoids was responsible for each observed transition from yellow to red plumage coloration, and has been commonly reported by other researchers. This suggests that the C4‐oxygenation pathway may be a readily evolvable means to gain red coloration using carotenoids.  相似文献   

12.
To understand the evolutionary processes leading to the diversity of Asian colobines, we report here on a phylogenetic, phylogeographical and population genetic analysis of three closely related langurs, Trachypithecus francoisi, T. poliocephalus and T. leucocephalus, which are all characterized by different pelage coloration predominantly on the head and shoulders. Therefore, we sequenced a 395 bp long fragment of the mitochondrial control region from 178 T. francoisi, 54 T. leucocephalus and 19 T. poliocephalus individuals, representing all extant populations of these three species. We found 29 haplotypes in T. francoisi, 12 haplotypes in T. leucocephalus and three haplotypes in T. poliocephalus. T. leucocephalus and T. poliocephalus form monophyletic clades, which are both nested within T. francoisi, and diverged from T. francoisi recently, 0.46-0.27 (T. leucocephalus) and 0.50-0.25 million years ago (T. poliocephalus). Thus, T. francoisi appears as a polyphyletic group, while T. leucocephalus and T. poliocephalus are most likely independent descendents of T. francoisi that are both physically separated from T. francoisi populations by rivers, open sea or larger habitat gaps. Since T. francoisi populations show no variability in pelage coloration, pelage coloration in T. leucocephalus and T. poliocephalus is most likely the result of new genetic mutations after the split from T. francoisi and not of the fixation of different characters derived from an ancestral polymorphism. This case study highlights that morphological changes for example in pelage coloration can occur in isolated populations in relatively short time periods and it provides a solid basis for studies in related species. Nevertheless, to fully understand the evolutionary history of these three langur species, nuclear loci should be investigated as well.  相似文献   

13.
Various polyclonal and monoclonal antibodies to keratins were used to stain different human muscle tissues by paired immunofluorescence and the unlabelled antibody peroxidase-anti-peroxidase method. In the myocardium, distinct coloration of the intercalated discs was produced by two polyclonal reagents to human epidermal keratins but not by two monoclonal antibodies to cytokeratins from pig renal tubular cells. In the myometrium--mainly in the middle layer of the uterine wall--cytoplasmic coloration of a varying fraction of the smooth muscle bundles was produced, especially by one of the polyclonal and by both monoclonal reagents. The staining was often confined to the perinuclear region. The keratin-positive myometrial cells usually coexpressed vimentin and actin in various proportions. These findings indicated that intermediate filaments of the keratin type, or antigenically similar elements, are not restricted to cells of epithelial origin. Other types of muscle cells did not react with keratin antibodies, but keratin-positive macrophages were occasionally found in tongue musculature and in inflamed epicardium. Altogether, our observations emphasize that keratin reactivity cannot be considered specific for epithelial (or mesothelial) cells without reservation.  相似文献   

14.
A rare species of the spariform fish Acanthopagrus schlegelii from Russian waters is described. The synonymy of this species and the related literature data are analyzed. It is suggested that two species occur in Russian waters that differ in body coloration: A. schlegelii and A. czerskii.  相似文献   

15.
Sexual selection often promotes the evolution of elaborate colour signals in males, but the importance of sexually selected colour signals remains poorly studied in amphibians. We used reflectance spectrometry to document pronounced sexual dichromatism and dramatic colour change in Bufo luetkenii, a toad that breeds in large aggregations at the onset of the rainy season in Costa Rica. Our observations suggest that males fade rapidly from a vibrant lemon yellow to a dull brown once they have paired with a female. We demonstrate this by showing that males are much brighter than females and that unpaired males are more colourful than males in amplexus. We also show that coloration fades rapidly when males are briefly held captive. This is, to our knowledge, the first study to document such dynamic change in male coloration and sexual dichromatism in anurans.  相似文献   

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17.
Two new Cyprinoid species are described from Phu Quoc Island, Gulf of Thailand. The first new species, Barbucca elongata sp. nova (Balitoridae), differs from the species B. diabolica, which is described previously, in more elongated body covered by small scales (50–67 perforated lateral line scales), conical snout, and coloration. The second new species, Rasbora vietnamensis sp. nova (Cyprinidae), belongs to the species group “R. trifasciata”; it differs from other species of the group in substantially reduced lateral line system with four-seven perforated scales and absence of red pigmentation on the fins and body.  相似文献   

18.
We investigated the potential roles in behavioral interactions of sexually dichromatic iridescent blue coloration found on the dorsal hindwing of male Pipevine Swallowtails (Battus philenor). Behavioral experiments in a large enclosure addressed whether male dorsal hindwing coloration mediated sexual recognition by males, female choice of mates, or both. Models presented to males in the enclosure produced responses that show that males discriminate females from other males using chemical but not visual cues. In contrast, ablation of male dorsal iridescence significantly reduced male mating success with virgin females in the enclosure. The results support the hypothesis that male-specific iridescent coloration in this species is a signal that is important for females in assessing either male species identity or quality in intersexual interactions.  相似文献   

19.
《Translational oncology》2020,13(10):100807
Lipid metabolic reprogramming is one hallmark of cancer. Lipid metabolism is regulated by numerous enzymes, many of which are targeted by several drugs on the market. We aimed to characterize the lipid alterations in oral squamous cell carcinoma (OSCC) as a basis for understanding its lipid metabolism, thus identifying potential therapeutic targets. We compared lipid species, classes, and glycerophospholipid (GPL) fatty acid species between paired tumor tissue and healthy oral tongue mucosa samples from 10 OSCC patients using a QExactive mass spectrometer. After filtering the 1370 lipid species identified, we analyzed 349 species: 71 were significantly increased in OSCC. The GPL metabolism pathway was most represented by the lipids differing in OSCC (P = .005). Cholesterol and the GPLs phosphatidylcholines, phosphatidylethanolamines, and phosphatidylinositols were most significantly increased in OSCC tissue (FC 1.8, 2.0, 2.1, and 2.3 and, P = .003, P = .005, P = .002, P = .007). In conclusion, we have demonstrated a shift in the lipid metabolism in these OSCC samples by characterizing the detailed landscape. Predominantly, cholesterol and GPL metabolism were altered, suggesting that interactions with sterol regulatory binding proteins may be involved. The FA composition changes of the GPLs suggest increased de novo lipogenesis.  相似文献   

20.
We analyzed the evolution of red/orange flowers in four putatively bird-pollinated species of Macaronesian Lotus, with the aim of investigating whether this floral trait evolved from a similar trait found in some entomophilous Lotus species, namely the ability to modify flower color to red after anthesis. First, we mapped the ability to modify flower color in this group on a well-resolved and densely sampled phylogenetic tree of the Macaronesian Lotus. Secondly, we determined differences in light reflectance and pigment composition between petals of (1) prechange and postchange flowers in bee-pollinated species and (2) between bee and putatively bird-pollinated species. Post-anthesis flower color change evolved three times within Macaronesian Lotus, and putatively bird-pollinated species evolved within a clade with this ability to change flower color to red after anthesis. The evolutionary transition to red/orange flowers in the putatively bird-pollinated species involved biochemical changes similar to those of the developmental transition to red postchange flowers. In both cases there are changes in the composition of flavonols and anthocyanidins within the same metabolic pathways, especially in the cyanidin branch of pigment production, but not the activation or inactivation of additional branches of this pathway. Post-anthesis color change in Lotus, from yellow to red, is thought to be an adaptation to reduce bee visits to already pollinated flowers. Our results are consistent with the hypothesis that constitutive red coloration for bird-pollination evolved from facultative red flower color change in Lotus. As red post-anthesis coloration is widespread in plants, this may possibly represent a widespread exaptive mechanism for the evolution of bird pollination.  相似文献   

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