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Novel water and dye-free heat treatment method was used to color wool yarn. The heat treatment can not only give the white wool yarn new color but also minimize the yarn hairiness. The influences of heating treatment temperature and time on the wool yarn color were investigated. The microstructure, twist, hairiness, wear resistance, moisture regain and tensile strength of the wool yarn were evaluated to analyze the physical and mechanical properties changes after heat treatment. The results showed that the color strength of wool yarn increased with increasing the heat treatment temperature and time. The hairs equal to or longer than 3 mm reduced significantly after heat treatment. The microstructural structure has no significant change after heat treatment, the unique overlapping scales structure on the surface still observed clearly by the SEM. The tensile strength and wear resistance of wool yarn would decrease with increasing heat treatment temperature and time, and the tensile strength retention was higher than 80% after heat treatment which could meet the requirement in daily applications. Therefore, the heat treatment is an environmentally friendly method to endow wool yarn color and it has a potential in the textile industry.

Abstract Warning signals are often characterized by highly contrasting, distinctive, and memorable colors. Greater chromatic (hue) and achromatic (brightness) contrast have both been found to contribute to greater signal efficacy, making longwave colored signals (e.g., red and yellow), that are perceived by both chromatic and achromatic visual pathways, particularly common. Conversely, shortwave colors (e.g., blue and ultraviolet) do not contribute to luminance perception yet are also commonly found in warning signals. Our understanding of the role of UV in aposematic signals is currently incomplete as UV perception is not universal, and evidence for its utility is at best mixed. We used visual modeling to quantify how UV affects signal contrast in aposematic heliconiian butterflies and poison frogs both of which reflect UV wavelengths, occupy similar habitats, and share similar classes of predators. Previous work on butterflies has found that UV reflectance does not affect predation risk but is involved in mate choice. As the butterflies, but not the frogs, have UV‐sensitive vision, the function of UV reflectance in poison frogs is currently unknown. We found that despite showing up strongly in UV photographs, UV reflectance only appreciably affected visual contrast in the butterflies. As such, these results support the notion that although UV reflectance is associated with intraspecific communication in butterflies, it appears to be nonfunctional in frogs. Consequently, our data highlight that we should be careful when assigning a selection‐based benefit to the presence of UV reflectance.

Abstract Background Blowflies are ubiquitous insects, often shiny and metallic, and the larvae of many species provide important ecosystem services (e.g., recycling carrion) and are used in forensics and debridement therapy. Yet, the taxon has repeatedly been recovered to be para- or polyphyletic, and the lack of a well-corroborated phylogeny has prevented a robust classification. Results We here resolve the relationships between the different blowfly subclades by including all recognized subfamilies in a phylogenomic analysis using 2221 single-copy nuclear protein-coding genes of Diptera. Maximum likelihood (ML), maximum parsimony (MP), and coalescent-based phylogeny reconstructions all support the same relationships for the full data set. Based on this backbone phylogeny, blowflies are redefined as the most inclusive monophylum within the superfamily Oestroidea not containing Mesembrinellidae, Mystacinobiidae, Oestridae, Polleniidae, Sarcophagidae, Tachinidae, and Ulurumyiidae. The constituent subfamilies are re-classified as Ameniinae (including the Helicoboscinae, syn. nov.), Bengaliinae, Calliphorinae (including Aphyssurinae, syn. nov., Melanomyinae, syn. nov., and Toxotarsinae, syn. nov.), Chrysomyinae, Luciliinae, Phumosiinae, Rhiniinae stat. rev., and Rhinophorinae stat. rev. Metallic coloration in the adult is shown to be widespread but does not emerge as the most likely ground plan feature. Conclusions Our study provides the first phylogeny of oestroid calyptrates including all blowfly subfamilies. This allows settling a long-lasting controversy in Diptera by redefining blowflies as a well-supported monophylum, and blowfly classification is adjusted accordingly. The archetypical blowfly trait of carrion-feeding maggots most likely evolved twice, and the metallic color may not belong to the blowfly ground plan.

This study was performed to investigate the interaction effects of astaxanthin and beta-carotene pigments in white and red lights on growth performance and coloration of swordtail, Xiphophorus helleri. A total of 180 swordtail with an average weight of 1.4 ± 0.1 g with three diets containing 150 mg/kg astaxanthin, 150 mg/kg beta-carotene and a diet without additive pigment and treatments in contrast to white and red lights with light intensity of 1200 lux was fed in 6 treatments and 3 replications for 8 weeks. Finally, growth indices including body weight gain, specific growth rate, feed conversion ratio and survival rate were determined. In order to determine the number of changes in color intensity and sharpness, Hue and Chroma coefficients were determined after shooting and analyzing the obtained colors using coefficients a and b with Photoshop software in the fourth and eighth weeks. The results revealed that there was no interaction between diets and ambient light, but fish raised in white light were superior in terms of all growth and survival indices (p

Abstract Background Production, marketability and consumer preference of red tilapia often depends upon the intensity of coloration. Hence, new approaches to develop coloration are now geared to improve market acceptability and profit. This study evaluated the effects of carotenoid-rich diets on the phenotypic coloration, carotenoid level, weight gain and expression of coloration-linked genes in skin, fin and muscle tissues. Carotenoids were extracted from dried Daucus carota peel, Ipomoea aquatica leaves, and Moringa oleifera leaves. Eighty (80) size-14 fish were fed with carotenoid-rich treatments twice a day for 120 days. The phenotypic effect of the carotenoid extracts was measured through a color chart. Skin carotenoid level was measured through UV-vis spectrophotometer. csf1ra, Bcdo2 and StAR expression analysis was done using qRT-PCR. Results Treatments with carotenoid extracts yielded higher overall scores on phenotypic coloration and tissue carotenoid levels. Differential expression of carotenoid-linked genes such as the elevated expression in csf1ra and lower expression in Bcdo2b following supplementation of the enhanced diet supports the phenotypic redness and increased carotenoid values in red tilapia fed with D. carota peel and I. aquatica leaves. Conclusions Overall improvement in the redness of the tilapia was achieved through the supplementation of carotenoid-rich diet derived from readily available plants. Differential expression of coloration-linked genes supports the increase in the intensity of phenotypic coloration and level of carotenoids in the tissues. The study emphasizes the importance of carotenoids in the commercial tilapia industry and highlights the potential of the plant extracts for integration and development of feeds for color enhancement in red tilapia.

To elucidate the molecular mechanisms underlying the differential metabolism of albino (white), green, and purple pericarp coloration, biochemical profiling and transcriptome sequencing analyses were performed on three different tea pericarps, Zhongbaiyihao (Camellia sinensis L. var. Zhongbai), Jinxuan (Camellia sinensis L. var. Jinxuan), and Baitangziya (Camellia sinensis L. var. Baitang). Results of biochemical analysis revealed that low chlorophyll content and low chlorophyll/carotene ratio may be the biochemical basis for albino characteristics in the ‘Zhongbaiyihao’ pericarp. The differentially expressed genes (DEGs) involved in anthocyanin biosynthesis, including DFR, F3′5′H, CCoAOMT, and 4-coumaroyl-CoA, were highly expressed in the purple ‘Baitangziya’ pericarp. In the chlorophyll synthesis of white pericarp, GUN5 (Genome Uncoupled 5) and 8-vinyl-reductase both showed high expression levels compared to the green one, which indicated that albino ‘Zhongbaiyihao’ pericarp had a higher chlorophyll synthesis capacity than ‘Jinxuan’. Meanwhile, chlorophyllase (CLH, CSS0004684) was lower in ‘Baitang’ than in ‘Jinxuan’ and ‘Zhongbaiyihao’ pericarp. Among the differentially expressed transcription factors, MYB59, WRKY41-like2 (CS ng17509), bHLH62 like1 (CS ng6804), and bHLH62-like3 (CSS0039948) were downregulated in Jinxuan pericarp, suggesting that transcription factors played a role in regulating tea pericarp coloration. These findings provide a better understanding of the molecular mechanisms and theoretical basis for utilizing functional components of tea pericarp.

The present study described in detail the occurrence of polychromatism in two peacock bass species (Cichla kelberi and Cichla piquiti) endemic to the Tocantins-Araguaia Basin, Brazil. Based on the data collected in the Lajeado Reservoir between 2010 and 2020, we analyzed the photographs obtained from live individuals in order to describe the range of color variation in the body, fins, and other aspects (spots, ocelli, and bars) and calculated the frequency of color patterns in each species. The results indicated wide variation in body coloration of C. kelberi, ranging from yellow (golden, dark, light, and greenish) to gray (gray, brown, and black) patterns; most fish had different shades of yellow. All fish had three vertical bars, but their sharpness was variable, and some fish had additional faint bars. The operculum region showed colorful patterns (red), but it was highly variable among individuals. Some fish had small dark blotches on the body and whitish-yellow spots on the fins. Cichla piquiti also showed wide variation in body coloration, including gray (with blue hues), yellow, and brown patterns, which were evenly observed in the population. Fish had four to five vertical bars, but some individuals had additional faint bars. The operculum region showed light yellow hues, with little variation. White spots were recorded in the body of some fish, including adults and young; in some, white spots formed unique patterns in the head. Our results demonstrate extensive polychromatism within native populations of both species, a pattern likely associated with ontogenetic changes and the reproductive cycle. [ABSTRACT FROM AUTHOR]

Melanin is the basis of coloration in many animals, and although it is often used in communication, thermoregulation, or camouflage, melanin has many other physiological functions. For example, in polluted habitats, melanin can have a detoxifying function. Melanic coloration would help to sequester in the skin the heavy metal contaminants from inside the body, which will be expelled to the exterior when the skin is sloughed. Moreover, animals should have evolved more melanic colorations in more polluted habitats ("industrial melanism" hypothesis). We examined whether the fossorial amphisbaenian reptile, Trogonophis wiegmanni, is able to eliminate heavy metals, derived from soil pollution by seagull depositions, through sloughing its skin. Our results suggest a covariation between levels of soil pollution by heavy metals and the concentration of heavy metals in the sloughed skins of amphisbaenians. This suggests that amphisbaenians may expel heavy metals from their bodies when they slough the skins. We also tested whether amphisbaenians inhabiting soils with higher levels of heavy metal pollution had darker (melanin‐dependent) body colorations. However, contrary to predictions from the "industrial melanization" hypothesis, we found a negative relationship between soil pollution and proportions of melanic coloration. This contradictory result could, however, be explained because heavy metals have endocrine disruption effects that increase physiological stress, and higher stress levels could result in decreased melanogenesis. We suggest that although amphisbaenians might have some detoxifying mechanism linked to melanin in the skin, this process might be negatively affected by stress and result ineffective under conditions of high soil pollution. [ABSTRACT FROM AUTHOR]

Temperature change is an often‐assumed, but rarely tested, mechanism by which sensitive species may decline in forest landscapes following habitat degradation, fragmentation and destruction.Traits mediate how species respond to environmental change, with physiological, morphological and behavioural traits key to determining the response of ectotherms to temperature.We collected data on traits linked to thermal sensitivity (critical thermal maxima, body size, cuticle lightness and pilosity) for 46 dung beetle species (Scarabaeinae) in a forest–oil palm mosaic in Malaysian Borneo. By combining these data with a large‐scale community sampling campaign (>59,000 individuals sampled from >600 traps) and an airborne Light Detection and Ranging‐derived thermal map, we investigated how traits mediate species‐ and community‐level responses to temperature.Using hierarchical models, we found that critical thermal maxima predicted how species respond to maximum temperatures. These results were mirrored in community‐level analyses alongside similar patterns in other thermal traits. Increased body size and decreased pilosity were associated with higher temperatures, while cuticle lightness showed a complex relationship with temperature across the disturbance gradient.Our findings highlight the potential mechanisms by whichforest specialists decline in human‐modified landscapes, resulting in changes to community patterns and processes. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Besides the importance of pigmentation in species recognition, pigments protect the body against different biotic and abiotic features. Melanin, the dark coloration pigments in skin, hairs, and feathers, is necessary for protecting the body from UV radiation. On the other hand, the lighter a surface is, the more solar radiation is reflected. Based on these arguments, it is possible that pigment distribution would not be the same among all body regions of a unicolored individual due to the amount of solar exposure. Therefore, three species of the Egretta genus (E. dimorpha, E. gularis, and E. garzetta) in which all individuals are unicolored, and two of which are dichromatic (dark grey/black and white), were selected as model studies. We hypothesized that within dark and white unicolored Egrets, due to foraging and standing postures, body regions that are more exposed to the sun (like back and breast) would be darker or whiter compared to other body regions (vent and tail), respectively. Visual wavelength reflections of five body regions (breast, back, belly, vent, and tail) from 186 museum specimens were measured to indicate the concentration of pigments in each body region. Reflectance among body regions was compared using Kruschke's 'BEST' (Bayesian Estimation Supersedes the t test) framework to create Bayesian analogues for the paired t‐test. The results show, regardless of the species, that the more exposed body regions to the sun (back followed by breast) are darker among dark individuals and whiter among white individuals in comparison to other body regions. Therefore, our hypothesis that the concentration of pigments is not similar in all body regions of unicolored individuals was supported. [ABSTRACT FROM AUTHOR]

Multicolored Jacquard artwork reproduction has been limited by the current setting of weaving machinery. Novel weaving applications have been introduced to overcome these current restrictions. The subtractive cyan, magenta, yellow and black system used for color printing has been important in optical yarn color mixing of Jacquard color production, because a wide scope of weave color production is possible with a small number of weft yarns. Previously, cyan, magenta, and yellow channels have been modified to resolve current restrictions in reproducing saturated black and secondary colors, but these experiments have not been successful. However, the generation of secondary color ranges is possible by mixing a pair of cyan, magenta, and yellow color yarns. In addition, it is feasible to control chroma levels of primary and secondary colors by mixing with a black yarn. Therefore, the potential of using four weft yarn colors is re-examined for the reproduction of multicolored artworks in relation to cost and production efficiency. Based on a mathematical morphology theory, cyan, magenta, and yellow color channels are altered in the use of image processing tools offered by Adobe Photoshop. A pair of the three color channels is combined under mathematical functions and they are modified through four steps. As a result, new cyan, magenta, and yellow color channels are created to optimize optical yarn color mixing effects. This study introduces details of the cyan, magenta, and yellow channel modification process and experiment results that examine the significance of the newly developed cyan, magenta, and yellow color channels. [ABSTRACT FROM AUTHOR]

Coloration of animals is important for camouflage, for social behavior, or for physiological fitness. This study investigates the color variation in adults of Aglais urticae obtained on subjecting some pre‐imaginal stages to different temperature conditions and their thermobiological consequences. To investigate the evolutionary–ecological interactions of temperature and pigmentation in butterflies, caterpillars, and pupae of the small tortoiseshell, Aglais urticae (Lepidoptera, Nymphalidae), larvae from Central Europe and Scandinavia were reared at temperatures between 7 and 34°C in the laboratory or in the field. After emergence, the intensity of pigmentation of the imagines and their increase in body temperature under defined full‐spectrum light irradiation were quantified by image analysis and thermal imaging. At constant conditions, ambient rearing temperature and pigmentation intensity of imagines were negatively and linearly correlated in Central European butterflies, regardless of whether the pupal stage alone or, additionally, the last period of the larval stage was exposed to these conditions: low temperatures induced darker coloration and high temperatures led to lighter individuals. A thermal pulse of a few days alone at the beginning of pupal dormancy led to a similar, albeit weakened, effect. Caterpillars of the Scandinavian subspecies A. urticae polaris, whose pupal dormancy took place under Central European field conditions, developed into strongly pigmented imagines. The thermobiological relevance of more intense pigmentation was shown by significantly higher absorption of light, and thus stronger increased body temperature after 5 min of defined illumination, but this difference ceased after 15 min. Our results show that phenotypic plasticity in wing coloration is adaptive since temperature‐induced developmental changes provide thermobiological benefit in adult butterflies. We propose that, in subpolar latitudes, darker coloration likely has a selection advantage favoring individuals with reaction norms gradually shifted to stronger pigmented phenotypes, possibly leading to the establishment of a pigmentation cline. [ABSTRACT FROM AUTHOR]

Objectives: Hair (i.e., pelage/fur) is a salient feature of primate (including human) diversity and evolution—serving functions tied to thermoregulation, protection, camouflage, and signaling—but wild primate pelage evolution remains relatively understudied. Specifically, assessing multiple hypotheses across distinct phylogenetic scales is essential but is rarely conducted. We examine whole body hair color and density variation across Indriidae (Avahi, Indri, Propithecus)—a lineage that, like humans, exhibits vertical posture (i.e., their whole bodies are vertical to the sun). Materials and methods: Our analyses consider multiple phylogenetic scales (family‐level, genus‐level) and hypotheses (e.g., Gloger's rule, the body cooling hypotheses). We obtain hair color and density from museum and/or wild animals, opsin genotypes from wild animals, and climate data from WorldClim. To analyze our data, we use phylogenetic generalized linear mixed models (PGLMM) using Markov chain Monte Carlo algorithms. Results: Our results show that across the Indriidae family, darker hair is typical in wetter regions. However, within Propithecus, dark black hair is common in colder forest regions. Results also show pelage redness increases in populations exhibiting enhanced color vision. Lastly, we find follicle density on the crown and limbs increases in dry and open environments. Discussion: This study highlights how different selective pressures across distinct phylogenetic scales have likely acted on primate hair evolution. Specifically, our data across Propithecus may implicate thermoregulation and is the first empirical evidence of Bogert's rule in mammals. Our study also provides rare empirical evidence supporting an early hypothesis on hominin hair evolution. [ABSTRACT FROM AUTHOR]

The coloration of the apple fruit (Malus × domestica Borkh.) depends on pigment content. Light stimulus activates a broad range of photosynthesis-related genes, including carotenoids. The effect of light on two red commercial apple cultivars, 'Summer Prince' and 'Arisoo' at the juvenile stage were examined. Apple fruits were either bagged to reduce light irradiation or were exposed to direct, enhanced sunlight (reflected). The pigment content and the expression of carotenoid metabolism genes in the peel and flesh of apple fruits were significantly different between the shaded and the reflected parts. These parameters were also different in the two cultivars, highlighting the contribution of the genetic background. Further, a combination of light and transient overexpression of carotenogenic genes increased fruit coloration and pigment content in the variety 'RubyS'. Western blot analysis showed the expression of small heat shock proteins (smHSP) in lysates extracted from the reflected part of the fruits but not in the bagged fruits, indicating the activation of smHSP in response to heat generated by the reflected light. Therefore, the synergy between the genes and the environment dictates the color of apple fruits. [ABSTRACT FROM AUTHOR]

Pear (Pyrus L.) is one of the most important temperate fruit crops worldwide, with considerable economic value and significant health benefits. Red-skinned pears have an attractive appearance and relatively high anthocyanin accumulation, and are especially favored by customers. Abnormal weather conditions usually reduce the coloration of red pears. The application of exogenous sucrose obviously promotes anthocyanins accumulation in 'Kuerle Xiangli' (Pyrus sinkiangensis Yü); however, the underlying molecular mechanism of sucrose-mediated fruit coloration remains largely unknown. In this study, comprehensive transcriptome analysis was performed to identify the essential regulators and pathways associated with anthocyanin accumulation. The differentially expressed genes enriched in Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes items were analyzed. The transcript levels of some anthocyanin biosynthetic regulatory genes and structural genes were significantly induced by sucrose treatment. Sucrose application also stimulated the expression of some sugar transporter genes. Further RT-qPCR analysis confirmed the induction of anthocyanin biosynthetic genes. Taken together, the results revealed that sucrose promotes pear coloration most likely by regulating sugar metabolism and anthocyanin biosynthesis, and this study provides a comprehensive understanding of the complex molecular mechanisms underlying the coloration of red-skinned pear. [ABSTRACT FROM AUTHOR]

To date, brilliant-blue pigments that can maintain outstanding stability in a corrosive environment over 1273 K are still very desirable in the ceramic industry. We systematically investigated the structural, optical, colorimetric and thermal properties of a novel type of CoNb 2 O 6 pigments, which have the 6-fold coordinated Co2+ as chromophores and high-valent Nb5+ as the mainstay factor for structural stabilization. Effective coloring contribution from different visible-light regions, the coloration mechanism and thermal stability of the pigments applied in glaze at 1273–1473 K are revealed for the first time. The Co2+ cation at the distorted [CoO 6 ] octahedra generates the brilliant blue hue, which can maintain the absolute blueness values, b *, at 30–44 even after glaze calcination at 1273–1423 K. The superb thermal performance in a harsh environment of the CoNb 2 O 6 pigments significantly outperforms the classic CoAl 2 O 4 blue, thereby exhibiting attractive prospects for high-end blue-sky–hued decoration for ceramics. [ABSTRACT FROM AUTHOR]

Color is the most intuitive indicator to determine the appearance quality of citrus. There are large differences in the color transition rate and color transition initiation region between mandarin fruit colored on-tree or during postharvest storage. Here, we obtained CcbHLH66, a transcription factor that could be related in the controlling of mandarin fruit coloration, from the transcriptome data of mandarin fruit colored on-tree and colored during postharvest storage. And verified its function in the regulation of mandarin fruit coloration by transient overexpression system of Nicotiana benthamiana and mandarin peel. The results showed that CcbHLH66 is localized in the nucleus with transcriptional activation activity. Overexpression of CcbHLH66 could promote yellowing of Nicotiana benthamiana and green ripe mandarin, and significantly reduce the amounts of chlorophyll and its metabolites in tobacco leaves and mandarin fruit peels. However, it had no significant effect on the amounts of carotenoids and their metabolites in mandarin fruit peels. Meanwhile, it could promote the expression of tobacco chlorophyll degrading genes NbSGR, NbNYC and NbRCCR, while repressing the expression of chlorophyll synthesizing gene NbCAO. The expression levels of chlorophyll metabolism-related genes CcNYC , CcPAO , CcRCCR , CcSGR , and CcChlase -2 were significantly up-regulated and the expression of CcChlase-1 was inhibited in mandarin fruit peel. EMSA and DLR experiments further showed that CcbHLH66 directly binds to and activates the key chlorophyll degradation genes CcRCCR and CcNYC. In summary, CcbHLH66 is an important coloration-related transcription factor in mandarin fruit, which accelerates the coloration process of mandarin by regulating the degradation of chlorophyll in the peel. • CcbHLH66 is a transcriptional activator with nuclear localization signals. • Overexpression of CcbHLH66 promotes leaf yellowing in Nicotiana benthamiana. • Overexpression of CcbHLH66 accelerates coloration of mandarin fruit. • CcbHLH66 binds directly to the G-box in the promoters of CcRCCR and CcNYC. [ABSTRACT FROM AUTHOR]

Abstract Coloration of animals is important for camouflage, for social behavior, or for physiological fitness. This study investigates the color variation in adults of Aglais urticae obtained on subjecting some pre‐imaginal stages to different temperature conditions and their thermobiological consequences. To investigate the evolutionary–ecological interactions of temperature and pigmentation in butterflies, caterpillars, and pupae of the small tortoiseshell, Aglais urticae (Lepidoptera, Nymphalidae), larvae from Central Europe and Scandinavia were reared at temperatures between 7 and 34°C in the laboratory or in the field. After emergence, the intensity of pigmentation of the imagines and their increase in body temperature under defined full‐spectrum light irradiation were quantified by image analysis and thermal imaging. At constant conditions, ambient rearing temperature and pigmentation intensity of imagines were negatively and linearly correlated in Central European butterflies, regardless of whether the pupal stage alone or, additionally, the last period of the larval stage was exposed to these conditions: low temperatures induced darker coloration and high temperatures led to lighter individuals. A thermal pulse of a few days alone at the beginning of pupal dormancy led to a similar, albeit weakened, effect. Caterpillars of the Scandinavian subspecies A. urticae polaris, whose pupal dormancy took place under Central European field conditions, developed into strongly pigmented imagines. The thermobiological relevance of more intense pigmentation was shown by significantly higher absorption of light, and thus stronger increased body temperature after 5 min of defined illumination, but this difference ceased after 15 min. Our results show that phenotypic plasticity in wing coloration is adaptive since temperature‐induced developmental changes provide thermobiological benefit in adult butterflies. We propose that, in subpolar latitudes, darker coloration likely has a selection advantage favoring individuals with reaction norms gradually shifted to stronger pigmented phenotypes, possibly leading to the establishment of a pigmentation cline.

To investigate the effects of dietary astaxanthin on fish growth and body color, blood parrotfish juveniles were assigned to three groups: control (CL), fed a diet without astaxanthin supplementation for 12 weeks; coloration (ASTA+), fed a diet containing 0.45 g/kg astaxanthin for 12 weeks; decoloration (ASTA-) fed the diet supplemented with astaxanthin for the first six weeks and then the control diet for the other six. Our results showed that the specific growth rate showed no significant difference between ASTA+ and CL at weeks 3 and 6 and among ASTA+ , ASTA- and CL at weeks 9 and 12. The ASTA+ group showed higher skin redness at weeks 3, 6, 9 and 12 and higher yellowness at weeks 6, 9 and 12 than CL, and than ASTA- at week 12. The ASTA+ group had higher concentrations of astaxanthin, HDL-C and LDL-C than the CL at weeks 3, 6, 9, and 12 and than ASTA- group at weeks 9 and 12. By compared ASTA+ and ASTA- with CL, a total of 4250 differentially expressed genes (DEGs) were detected. Pathways, e.g., PPRA signaling pathway, fatty acid degradation, and ABC transporters, of DEGs involved in carotenoid deposition were enriched. DEGs involved in the absorption and transport (e.g., upregulated lpl and pltp, and downregulated stard7), metabolism (e.g., upregulated adh1 and dhrs7cb, and downregulated cyp7b1, dhrs11, and si:ch211-113j14.1), and deposition of carotenoids (e.g., downregulated apoa1b and apodb) might be associated with skin coloration. Overall, the results of this study could help to understand the biochemical and molecular mechanism of body coloration under the presence and absence of dietary astaxanthin in blood parrotfish.

The quality of Pyropia haitanensis (T. J. Chang & B. F. Zheng) N. Kikuchi & M. Miyata (Porphyra haitanensis) is directly affected by nutrient availability. However, the molecular mechanism underlying the synergistic regulatory effects of nitrogen (N) and phosphorus (P) availability on P. haitanensis quality is unknown. Here, we performed physiological and multi-omics analyses to reveal the combined effects of N and P on P. haitanensis quality. The pigments accumulated under high N because of increases in N metabolism and porphyrin metabolism, ultimately resulting in intensely colored thalli. High N also promoted amino acid metabolism and inosine 5′-mononucleotide (IMP) synthesis, but inhibited carbohydrates accumulation. This resulted in increased amino acid, IMP and decreased agaro-carrageenan and cellulose contents, thereby improving the nutritional value and taste. Furthermore, high P promoted carbon metabolism and amino acid metabolism.This study provided the basis for elucidating the mechanism behind N and P regulating the seaweed quality. [Display omitted] • Compared with P, N had a greater effect on Pyropia haitanensis quality. • High N promoted the uptake of P. • High N deepened the thallus color by promoting N and porphyrin metabolism. • High N improved flavor by inhibiting carbohydrate, promoting amino acid and IMP synthesis. • High N and P levels synergistically stimulate amino acid synthesis. [ABSTRACT FROM AUTHOR]

The multifunctional cotton fabrics, which were expected to become one of the most promising textile materials, gained much attention in the apparel market. In this work, the simultaneous coloration and finishing processes with natural dye were carried out to prepare the multifunctional cotton fabrics. The modification process using ammonium polyphosphate (APP) imparted the cotton fabric with numerous anionic sites along with flame retardant and anti-wrinkle properties. Subsequently, the implementation of coloration with berberine was to render the cotton fabric with elegant shade and anti-bacterial, ultraviolet (UV) protection performances. The obtained results revealed that the cotton fabric treated with APP could obtain deep shade. It was found that the limited oxygen index (LOI), wrinkle recovery angle (WRA), ultraviolet protection factor (UPF) and antibacterial efficiency of treated fabric were 46.4%, 252°, 193 and 99%, respectively. More importantly, the repeated laundering showed negligible influence on the flame retardant and anti-wrinkle performances. In addition, the anti-bacterial and UV protection performance of treated cotton fabric exhibited a slight decline even after 20 cycles of washing. Finally, the washing and rubbing fastness of obtained cotton fabric were also desirable. [Display omitted] • The synergistic effect of APP and berberine imparted cotton multi-function. • The anionic treatment of cotton using APP significantly enhanced dye exhaustion. • Application of APP endowed cotton with flame retardant and anti-wrinkle properties. • UV protection and anti-bacterial properties of cotton was improved using berberine. [ABSTRACT FROM AUTHOR]

A key challenge in animal behavior is disentangling the social stimuli that drive conspecific behaviors. For some species, like teleost fish, putative sexual signaling cues are inextricably linked to others, making it difficult to parse the precise roles distinct signals play in driving conspecific behaviors. In the African cichlid Astatotilapia burtoni , males are either dominant or subordinate, wherein bright coloration, territoriality, and courtship behavior inextricably correlate positively with rank. Here, we leveraged androgen receptor (AR) mutant male A. burtoni that lack dominance-typical coloration but not behavior to isolate the role of male coloration in driving female mating behaviors in this species. We found in independent behavioral assays that females behave aggressively towards AR mutant but not WT males, yet still mated with both types of males. Females showed enhanced activation of esr2b + cells in the hypothalamus when housed with either mutant or WT males and this activation scaled with spawning activities. Therefore, there is not a simple relationship between male coloration and female mating behaviors in A. burtoni , suggesting independent sensory mechanisms converge on hypothalamic esr2b cells to coordinate behavioral output. • Novel androgen receptor mutant male cichlids lack male color but behave normally. • Female cichlids are aggressive towards mutants but will mate with them. • Hypothalamic esr2b+ cell activation correlates with female mating behaviors. • Male color is one trait among many that females use to guide mating. [ABSTRACT FROM AUTHOR]

Pigmentation genes expressed in skin, body muscle and tail of Thai-flag compared with Blue, White and Red varieties of Siamese fighting fish Betta splendens were identified. In total, 22,919 new unigenes were found. Pearson correlation and PCA analysis revealed that expression profiles of genes in muscle, skin and tail across solid color variety were similar. In contrast, those in skin and red tail part of Thai-flag were closely related but they showed different expression profiles with the white tail part. Moreover, 21,347–64,965 SNPs were identified in exonic regions of identified genes. In total, 28,899 genes were differentially expressed between paired comparisons of libraries where 13,907 genes (48.12 %) were upregulated and 14,992 genes (51.88 %) were downregulated. DEGs between paired libraries were 106–5775 genes relative to the compared libraries (56–2982 and 50–2782 for upregulated and downregulated DEGs). Interestingly, 432 pigmentation genes of B. splendens were found. Of these, 297 DEGs showed differential expression between varieties. Many DEGs in melanogenesis (Bsmcr1r , Bsmcr5r , and Bsslc2a15b), tyrosine metabolism (Bstyr , Bstyrp1b and Bsdct), stripe repressor (BsAsip1 and BsAsip2b), pteridine (Bsgch2) and carotenoid (BsBco2) biosynthesis were downregulated in the Thai-flag compared with solid color varieties. Expression of Bsbco1l, Bsfrem2b , Bskcnj13 , Bszic2a and Bspah in skin, muscle and tail of Thai-flag, Blue, Red and White varieties was analyzed by qRT-PCR and revealed differential expression between fish varieties and showed anatomical tissue-preferred expression patterns in the same fish variety. The information could be applied to assist genetic-based development of new B. splendens varieties in the future. • Genes expressed in Thai-flag compared with solid-color varieties of Siamese fighting fish Betta splendens were identified. • Expression profiles of genes in each tissue of solid color varieties (Blue, White and Red) were similar. • In Thai-flag, gene expression profiles in skin and red tail part were closely related but different from the white tail part. • DEGs in melanogenesis, stripe repressor, pteridine and carotenoid biosynthesis were downregulated in the Thai-flag. • Bsbco1l, Bsfrem2b , Bskcnj13 , Bszic2a and Bspah were differentially expressed in different tissues of B. splendens. [ABSTRACT FROM AUTHOR]

Natural and synthetic astaxanthin can promote pigmentation in fish. In this study, the effects of dietary astaxanthin on growth and pigmentation were evaluated in leopard coralgrouper (Plectropomus leopardus). Fish were assigned to three groups: 0% astaxanthin (C), 0.02% natural astaxanthin (HP), and 0.02% synthetic astaxanthin (AS). Brightness (L*) was not influenced by astaxanthin. However, redness (a*) and yellowness (b*) were significantly higher for fish fed astaxanthin-containing diets than fish fed control diets and were significantly higher in the HP group than in the AS group. In a transcriptome analysis, 466, 33, and 32 differentially expressed genes (DEGs) were identified between C and HP, C and AS, and AS and HP, including various pigmentation-related genes. DEGs were enriched for carotenoid deposition and other pathways related to skin color. A metabolome analysis revealed 377, 249, and 179 differential metabolites (DMs) between C and HP, C and AS, and AS and HP, respectively. In conclusion, natural astaxanthin has a better coloration effect on P. leopardus, which is more suitable as a red colorant in aquaculture. These results improve our understanding of the effects of natural and synthetic astaxanthin on red color formation in fish.

Adult odonates (dragonflies and damselflies) exhibit a great diversity of colors which vary remarkably between species, between individuals within species, and throughout the individual's lifetime in some species. Here, we provide a summary of what is known about color recognition, and production of color including pigmentary absorption, structural reflectance, and fluorescence, in odonates. We also review the current understanding of the function of color in adult odonates, such as in signals during mate choice, in species recognition, and in predator avoidance, as well as in physiological adaptations to abiotic conditions. Finally, we provide some directions for future research: eye and pterostigma color, coloration at different life stages, UV color, phylogenetic analysis of color evolution, color and hot climate patterns, and standardization of color recordings. Given how easily they can be marked and tracked, odonates are exemplary animals for field and laboratory research. Therefore, unraveling the physiology, evolution, and ecology of odonate color can provide significant advances, in general, to understand insect color. [ABSTRACT FROM AUTHOR]

Albinism is a genetic disorder that causes pigmentation anomalies. Even though supposedly rare in free-living mammals, cases of albinism have been reported worldwide, particularly in bats. In this article we present a new case of albinism in a Lionycteris spurrelli Thomas, 1913. The individual, observed in an Amazon region iron ore cave, in Northern Brazil, was a lactating female with a dark-brown pelage pup. [ABSTRACT FROM AUTHOR]

Direct and ultrasensitive detection of nanoscale objects is of great importance for materials science and biomedical application. Here, a printed single nanoparticle array‐based coloration biochip is developed for direct visualizing nanoscale objects with the microscopy image. Arising from the scattering cross section induced Mie scattering enhancement, the color change of nanoparticles with/without viruses can be observed with a conventional optical microscope. The scattering light from single nanoparticle has the size‐dependent characteristics of wavelength and intensity variation, allowing for optically detecting nanoscale virus. By comparing optical images before and after attaching viruses, quantitative detection can be achieved with the virus concentrations from 1.0 × 102 to 1.0 × 106 PFU mL–1 and a detection limit of 1.0 × 102 PFU mL–1. The antibody‐modified array can specifically recognize influenza viruses in 15 min. The result provides a promising approach to detect diverse biological samples, including protein, exosomes, and platelet microparticle. [ABSTRACT FROM AUTHOR]

Variations in eye colour in birds are poorly documented. We measured and characterised eyes of 25 birds in the hand (16° × 22.5° segments per eye), using standardised and scaled images, and examined observations of 1 marked individual through time. We describe universal and extensive dark heterochromia (non-uniform colouration of the eye) in adult masked lapwings Vanellus miles novaehollandiae in our study population. Asymmetrical within-eye heterochromia has not previously been recorded for Charadridae, but in a review of images of eyes in the genus Vanellus, we found 45% of the 22 species had detectable heterochromia. There was a tendency (p = 0.051 after false discovery rate correction) for males to have slightly less black in the upper posterior part of the eye, a difference not distinguishable enough to aid sexing in the hand. We suggest standardised images of captured birds would underpin a more nuanced understanding of the occurrence of subtle heterochromia among birds, which may permit phylogenetic analyses directed at exploring possible evolution or function of such eye pigmentation. [ABSTRACT FROM AUTHOR]

Biotic resistance by the local community is a prominent theory seeking to explain invasion success or failure. Oceanic island communities might be prone to invasions because of their assumed low biotic resistance, due to low species richness and ecological naivety towards invaders. Biotic resistance, however, has rarely been quantified. We attempted such quantification on Terceira Island (Azores, Portugal) using the sentinel prey method. Vanessa virginiensis, a widely distributed Nearctic butterfly, has not been recorded on Terceira, and their caterpillars have characteristic green–black stripes that make it dissimilar to other Azorean caterpillars. We examined whether predation rate (PR) on plasticine caterpillars mimicking the unfamiliar V. virginiensis pattern were lower than on familiar green ones. We exposed a total of 4479 caterpillars in native forests and five non-native habitats, the agroecosystems orchards, vineyards, low and high elevation maize fields, and intensively managed pastures. Overall PR was higher on caterpillars with the unfamiliar than with the familiar pattern (6.4%d−1 vs. 3.7%d−1). Invertebrate PR was also significantly higher on the unfamiliar than on the familiar pattern in the native forest (5.9%d−1 vs. 1.0%d−1), as well as vertebrate PR in orchards (4.8%d−1 vs. 2.3%d−1) and low elevation maize fields (7.4%d−1 vs. 2.2%d−1). Our results suggest the existence of biotic resistance even on a species-poor, remote island, and that a novel morphological phenotype in itself does not guarantee reduced predation pressure. [ABSTRACT FROM AUTHOR]

Aposematic coloration is among the most diverse antipredator strategies, which can signal unpleasantness of organisms to potential predators and reduce the probability of predation. Unlike mimesis, aposematic coloration allows organisms to warn their predators away by conspicuous and recognizable colour patterns. However, aposematism has been a regular puzzle, especially as the long-term history of such traits is obscured by an insufficient fossil record. Here, we report the discovery of aposematic coloration in an orthopteran nymph from Mid-Cretaceous Kachin amber (99 million years old). It is attributed to the extinct family Elcanidae and erected as a new genus identified by conspicuous dark/light-striped coloration, four apical spurs on the metatibia, a two-segmented metatarsus and unsegmented stylus. It represents the first fossil orthopteran preserved with aposematic coloration from the Mesozoic, demonstrating that orthopterans had evolved aposematism by the Mid-Cretaceous. Our findings provide novel insights into the early evolution of anti-predator strategies among orthopterans. Together with mimesis, debris-carrying camouflage and aposematism previously reported, our findings demonstrate the relative complexity of prey-predator interactions in the Mesozoic, especially in the Mid-Cretaceous Kachin amber forest. [ABSTRACT FROM AUTHOR]

Parallel evolution, in which independent populations evolve along similar phenotypic trajectories, offers insights into the repeatability of adaptive evolution. Here, we revisit a classic example of parallelism, that of repeated evolution of brighter males in the Trinidadian guppy (Poecilia reticulata). In guppies, colonisation of low predation habitats is associated with emergence of 'more colourful' phenotypes since predator‐induced viability selection for crypsis weakens while sexual selection by female preference for conspicuousness remains strong. Our study differs from previous investigations in three respects. First, we adopted a multivariate phenotyping approach to characterise parallelism in multitrait space. Second, we used ecologically‐relevant colour traits defined by the visual systems of the two selective agents (i.e., guppy, predatory cichlid). Third, we estimated population genetic structure to test for adaptive (parallel) evolution against a model of neutral phenotypic divergence. We find strong phenotypic differentiation that is inconsistent with a neutral model but very limited support for the predicted pattern of greater conspicuousness at low predation. Effects of predation regime on each trait were in the expected direction, but weak, largely nonsignificant, and explained little among‐population variation. In multitrait space, phenotypic trajectories of lineages colonising low from high predation regimes were not parallel. Our results are consistent with reduced predation risk facilitating adaptive differentiation, potentially by female choice, but suggest that this proceeds in independent directions of multitrait space across lineages. Pool‐sequencing data also revealed SNPs showing greater differentiation than expected under neutrality, among which some are found in genes contributing to colour pattern variation, presenting opportunities for future genetic study. see also the Perspective by Rebecca C. Fuller. [ABSTRACT FROM AUTHOR]

Abstract Aposematic and sexual signals are often characterized by bright, highly contrasting colors. Many species can see colors beyond the human visible spectrum, and ultraviolet (UV) reflection has been found to play an important role in communication and sexual selection. However, the role of UV in aposematic signals is poorly explored. Poison frogs frequently produce high‐contrast signals that have been linked to both aposematism and intraspecific communication. Yet despite considerable efforts studying interspecific and intraspecific diversity in color, poison frogs are not known to perceive UV, and UV reflection of the integument has not been described. We report UV‐reflective spots in a population of Oophaga sylvatica and quantify the effect of UV on visual contrast with models of avian vision. We found that the frogs are highly contrasting, but UV had a minimal effect on signal saliency. These data highlight the importance of considering UV reflectance within aposematic signals, but that UV should not necessarily be regarded as an independent signal.

Abstract Direct and ultrasensitive detection of nanoscale objects is of great importance for materials science and biomedical application. Here, a printed single nanoparticle array‐based coloration biochip is developed for direct visualizing nanoscale objects with the microscopy image. Arising from the scattering cross section induced Mie scattering enhancement, the color change of nanoparticles with/without viruses can be observed with a conventional optical microscope. The scattering light from single nanoparticle has the size‐dependent characteristics of wavelength and intensity variation, allowing for optically detecting nanoscale virus. By comparing optical images before and after attaching viruses, quantitative detection can be achieved with the virus concentrations from 1.0 × 102 to 1.0 × 106 PFU mL–1 and a detection limit of 1.0 × 102 PFU mL–1. The antibody‐modified array can specifically recognize influenza viruses in 15 min. The result provides a promising approach to detect diverse biological samples, including protein, exosomes, and platelet microparticle.

Natural habitats are increasingly affected by anthropogenically driven environmental changes resulting from habitat destruction, chemical and light pollution, and climate change. Organisms inhabiting such habitats are faced with novel disturbances that can alter their modes of signaling. Coloration is one such sensory modality whose production, perception and function is being affected by human-induced disturbances. Animals that acquire pigment derivatives through diet are adversely impacted by the introduction of chemical pollutants into their environments as well as by general loss of natural habitat due to urbanization or logging leading to declines in pigment sources. Those species that do manage to produce color-based signals and displays may face disruptions to their signaling medium in the form of light pollution and turbidity. Furthermore, forest fragmentation and the resulting breaks in canopy cover can expose animals to predation due to the influx of light into previously dark environments. Global climate warming has been decreasing snow cover in arctic regions, causing birds and mammals that undergo seasonal molts to appear conspicuous against a snowless background. Ectotherms that rely on color for thermoregulation are under pressure to change their appearances. Rapid changes in habitat type through severe fire events or coral bleaching also challenge animals to match their backgrounds. Through this review, we aim to describe the wide-ranging impacts of anthropogenic environmental changes on visual ecology and suggest directions for the use of coloration both as an indicator of ecological change and as a tool for conservation.

The features of the coloration of the dorsal and ventral surfaces of the rare deep-sea Richardson's ray Bathyraja richardsoni (Arhynchobatidae) in the length range from 14 to 146 cm have been studied and its ontogenetic changes have been traced. New data on the coloration of embryos, immature, maturing, and sexually mature individuals are presented. It is shown that variations in the coloration of the dorsal surface are insignificant, while the coloration of the ventral surface can vary significantly. The data obtained can be used in taxonomic and population studies, in the development of keys for species identification, in the preparation of faunal overviews and field guides, to facilitate understanding the features of coloration and its changes in deep-sea animals living in permanent darkness, and to expand knowledge about certain aspects of macro- and microevolution of deep-sea skates. [ABSTRACT FROM AUTHOR]

The black scavenger fly Sepsis thoracica exhibits polyphenic development resulting in alternate small black and large amber male morphs. Although the behavior, ecology, and physiology of both morphs are being scrutinized, the evolutionary origins of the nutritional polyphenism remain poorly understood. I here use a comparative approach to study variation in the degree of melanization of the forefemur—a secondary sexual trait. Melanization showed nutritional plasticity in all species, and character mapping suggests polyphenic development to represent the ancestral character state that was lost repeatedly. That is, interspecific variation among the studied species is mainly caused by the loss and not the gain of polyphenic development. Coevolution between male melanization and mating system differences further implicates sexual selection in the evolution of male melanization. These findings highlight the usefulness of comparative and natural history data in shedding new light on the evolution of phenotypic variation. [ABSTRACT FROM AUTHOR]

Two new species of the aorid Amphipoda are described from Chichijima Island, the Ogasawara Islands in Japan. Aoroides macrops sp. nov. from shallow water is characterized by the heavily setose male gnathopod 1, the coxa of which bears several plumose setae anteriorly, and the uropod 2 with a short inter-ramal process. This species is very similar to A. longimerus Ren and Zheng, 1996; however, this new species can be distinguished from A. longimerus by the larger eyes, the shorter carpus of the male gnathopod 1, and the shorter carpi of the pereopods 3 and 4. Grandidierella ogasawarensis sp. nov. from river mouth has the male gnathopod 1 with two teeth on the carpus and an anterodistal projection on the propodus, the male gnathopod 2 with an elongate carpus, and the uropod 1 bearing an inter-ramal process. This new species is different from its closely related congeners (G. koa Barnard, 1977; G. insulae Myers, 1981; and G. rubroantennata Ariyama and Taru, 2017) in the separated teeth on the carpus of the male gnathopod 1. [ABSTRACT FROM AUTHOR]

As hybrid zones exhibit selective patterns of gene flow between otherwise distinct lineages, they can be especially valuable for informing processes of microevolution and speciation. The bumble bee, Bombus melanopygus, displays two distinct color forms generated by Müllerian mimicry: a northern "Rocky Mountain'' color form with ferruginous mid‐abdominal segments (B. m. melanopygus) and a southern "Pacific'' form with black mid‐abdominal segments (B. m. edwardsii). These morphs meet in a mimetic transition zone in northern California and southern Oregon that is more narrow and transitions further west than comimetic bumble bee species. To understand the historical formation of this mimicry zone, we assessed color distribution data for B. melanopygus from the last 100 years. We then examined gene flow among the color forms in the transition zone by comparing sequences from mitochondrial COI barcode sequences, color‐controlling loci, and the rest of the nuclear genome. These data support two geographically distinct mitochondrial haplogroups aligned to the ancestrally ferruginous and black forms that meet within the color transition zone. This clustering is also supported by the nuclear genome, which, while showing strong admixture across individuals, distinguishes individuals most by their mitochondrial haplotype, followed by geography. These data suggest the two lineages most likely were historically isolated, acquired fixed color differences, and then came into secondary contact with ongoing gene flow. The transition zone, however, exhibits asymmetries: mitochondrial haplotypes transition further south than color pattern, and both transition over shorter distances in the south. This system thus demonstrates alternative patterns of gene flow that occur in contact zones, presenting another example of mito‐nuclear discordance. Discordant gene flow is inferred to most likely be driven by a combination of mimetic selection, dominance effects, and assortative mating. [ABSTRACT FROM AUTHOR]

Comparative studies indicate that several mammalian clades obey Gloger's rule in that they exhibit darker coloration in humid warm climates, although the mechanisms responsible for this association still are poorly understood. We surveyed external appearances of a single species, the feral pig (Sus scrofa), shot at 48 hunting lodges across North America and matched these to potential abiotic drivers, namely: relative humidity, temperature, precipitation, and ultraviolet (UV) radiation, and to biotic factors of habitat shade and predation pressure. We found that darker animals occupy locations of greater precipitation and warmer temperatures, as expected from Gloger's rule. The recent range expansion of S. scrofa implies selection for pelage coloration has occurred very rapidly. Separating pelage coloration into eumelanin- and phaeomelanin-based pigmentation, we found more pronounced eumelanin-based pelage in areas of higher rainfall and temperatures and UV radiation, whereas pelage phaeomelanin is related to cool dry climates with lower UV radiation. This implies that humidity or UV protection but not crypsis are the mechanisms underlying Gloger's rule in this species and the factors driving eumelanin and phaeomelanin expression in mammalian pelage are different, reinforcing new interpretations of this venerable rule. [ABSTRACT FROM AUTHOR]

The poison frog Epipedobates anthonyi is a species of the Dendrobatidae family distributed in a restricted area in Ecuador and Peru; it has high chromatic variation in Ecuadorian populations. An individual with partial leucism was registered in the Province of El Oro-Ecuador. It is the first case formally reported from this species and in the country. This note describes the record and presents photographs to compare a leucistic individual with one with the normal coloration of the area. [ABSTRACT FROM AUTHOR]

Plumage pigmentation is fundamental to a bird's phenotype, with pigment deposition causing relative crypsis or conspicuousness, depending on the environmental context. Geographic variation in plumage melanin tends to be predictable, suggesting that aspects of climate cause local matching of plumage to environment via genetic adaptation. Ecogeographic rules describe this predictability: Gloger's rule predicts that populations in wetter and warmer environments will be more pigmented; Bogert's Rule predicts more pigmentation in cold environments. The Great Horned Owl (Bubo virginianus) exhibits extensive geographic variation in the degree of melanin-based pigmentation. We examined fine-scale spatial variation in owl plumage melanism along environmental gradients in southwestern North America. We tested whether variation is explained by either of two non-mutually exclusive hypotheses: (1) a history of allopatric divergence between subspecies or (2) in situ local adaptation consistent with ecogeographic rules. The allopatric divergence hypothesis predicts a bimodal distribution of plumage melanism, with a geographic cline across a zone of secondary contact, whereas the local adaptation hypothesis predicts that climate explains variation independently of geography. Using a colorimeter, we measured coloration in 101 museum specimens of breeding-season Great Horned Owls that had been obtained from variable environments and elevations. Specimens previously identified as separate subspecies were distinguishable by colorimetry. Plumage lightness, however, was continuously distributed, rather than bimodal. While accounting for males having reduced pigmentation relative to females, linear models revealed that lighter plumage was associated with low latitude, low elevation, high temperature, and low precipitation. These findings suggest that variation in Great Horned Owl plumage pigmentation is best understood as continuous ecogeographic variation, consistent with ecogeographic predictions, and currently maintained in situ along multiple environmental gradients that characterize the "sky island" topography of the southwestern USA. [ABSTRACT FROM AUTHOR]

Background. The application of molecular-phylogenetic approaches to taxonomy has had a dramatic effect on our understanding of the diversity of reptiles. These approaches have allowed researchers to reveal previously hidden lineages as well as taxonomic overestimation in morphologically plastic taxa. Slow worms, legless lizards of the genus Anguis (Squamata: Anguidae), were previously considered to comprise either one or two species, and morphology-based intraspecific taxonomy of Anguis fragilis remained controversial throughout the 20th century. After the discovery of deep genetic divergences within the genus, its taxonomy was reconsidered, and as a result, five extant species have been recognized. In order to better understand the patterns of their interspecific differentiation, here we studied phenotypic differences between the two most widespread of them--A. fragilis and A. colchica, and their putative hybrids across the contact zone of both species in Central Europe. Methods. We used multivariate and univariate statistics and analyzed ten metric, eleven meristic, and six categorical phenotypic variables in material comprising a total of 326 individuals. We also genotyped individuals from the contact zone for one mitochondrial and two nuclear DNA fragments in order to delineate the distribution of individuals of hybrid and non-hybrid origin. The clines in morphological traits were studied using HZAR. Results. We show that the two species are morphologically differentiated. Anguis fragilis has a less robust head, fewer scales covering the body, lower frequency of the external ear opening presence, lower frequency of separated prefrontal scales, higher frequency of prefrontal scales in contact with each other, and body coloration more similar to the juvenile coloration than A. colchica. Slow worms from the contact/hybrid zone are characterized by an intermediate morphology, with more similarities to A. fragilis than to A. colchica. Discussion. None of the analyzed characters alone proved to be fully diagnostic, although more than 90% of all individuals could be successfully assigned to one or another species based on numbers of scales around the body. Our results indicate concordant, coincident, and steep clines in character states change. We present several hypotheses on the origin and evolutionary maintenance of the morphological divergence between both species and suggest that different evolutionary histories of the taxa rather than recently acting selection explain the observed morphological variation. [ABSTRACT FROM AUTHOR]

This study was designed to determine the ideal dosages of marigold (Tagetes erecta) and synthetic carotenoid in blue streak hap (Labidochromis caeruleus) and pindani (Pseudotropheus socolofi) fry (Cichlidae), and to compare effects on the growth and skin coloration. In the first experiment, the blue streak hap and pindani fry fed with different levels of water-soluble marigold flower meal (0, 2, 4, 6, 8, 10 and 12%) were tested for 30 days to find the optimum skin coloration and growth parameters. Then, in the experiment, the most effective doses of water-soluble marigold flower meal (2, 4, 8%) which obtained from the first experiment were compared with the different synthetic carotenoid dosages (50, 100 and 150 mg kg-1) for 30 days. At the end of the first experiment, weight gain and the skin coloration degrees for both fish species were increased significantly by supplementation of 4% water-soluble marigold flower meal supplemented diet (P

High susceptibility of wool toward bacterial growth owing to proteinous nature and moisture retention ability leads to need for antibacterial functionalization of wool to cure the resulting deterioration. Antibacterial colored wool was designed via application of Terminalia chebula, Alkanna tinctoria, and Tagetes erecta natural dyes. Characteristics in terms of color and antibacterial activity were compared to correlate coloring compound’s effect on characteristics of dyes and, both T. chebula and A. tinctoria dyes inferred themselves actively resisting bacterial growth while T. erecta was not efficient against bacterial strains. Colorful shades of good color and fastness properties were obtained from selected natural dyes on woolen yarn. Results show Bacillus subtilis and Staphylococcus aureus (gram positive) were highly resisted by the effect of T. chebula and A. tinctoria dyes, and T. chebula among them proved best in terms of both color characteristics and antibacterial potential.

Reactive dyes are chemically bonded to a cotton fibre surface. The anchor groups of dye molecules initiate this covalent bonding. In addition to this anchor group, reactive dyes also contain charged functional groups that are often negatively charged sulphonate groups –SO3-. These negative groups are part of the dye to enable its solubility in water. In industrial applications, dyes are applied as part of a water-based dye bath. The aim of the presented study was to improve the dyeing of cotton through the cationic modification of the textile, supporting an attraction to negatively charged dye molecules. In this way, the dye up-take and achieved colour depth should be improved. The current study was performed with a vinyl sulfone reactive dye. Three different nitrogen containing cationic organic substances were used for cotton pretreatment. In addition to colour properties, the antibacterial properties of prepared textile samples were also studied because antibacterial properties are often related to compounds containing amino and ammonium groups. Finally, it was shown that the cationic pretreatment with two of the three studied agents increased the dye up-take of cotton fabric from the dye bath. At the same time, one cationic agent can introduce antibacterial properties to treat cotton fabrics against two different types of bacteria: E. coli and S. warneri. The simultaneous application of a functional property during an optimised dyeing process was demonstrated in this case and can serve as an example for further applications.

Novolac resins are used to prepare high-performance flame-retardant fibers, which are also supplied under the brand name Kynol fibers. In the current study, Kynol fiber materials are treated with a laser beam to introduce dark coloration at distinct areas on the textile surface. By this, imaging and writing on the textile surface is possible. For investigation, two different types of Kynol fiber materials are used - a non-woven fiber felt and a woven fabric. It is shown that a laser treatment of medium intensity can introduce a change to dark coloration with good rubbing fastness. The writing of letters and symbols onto fabrics is possible. However, treatments with strong laser intensity lead to significant fiber damages and low rubbing fastness. Nevertheless, the presented method is a promising tool to apply images onto flame retardant fabrics from high performance fibers, which are difficult to dye using conventional techniques of dyeing and printing.