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Background: Skin is an important barrier of the human body, which offers protection from pathogens, UV radiation, and chemical and mechanical injury. Solar UV radiation is the major cause of extrinsic skin aging and it leads to many acute and chronic cutaneous reactions. Dermoscope is an instrument that helps to visualize the morphological features unseen to the naked eye, using the principle of transillumination and magnification of skin. Aim and Objective: The aim of the study was to study the skin changes associated with sun exposure on the lateral and medial aspects of the forearm using dermoscope. Materials and Methods: A cross-sectional descriptive study of 82 1st-year MBBS students belonging to 18-25 years of age was conducted at Government Medical College, Thrissur, after getting ethics committee approval. Sample size calculated was 76. With the help of a questionnaire, personal details and details related to the sun exposure habits of the subjects were obtained. Dermoscopic photographs of the lateral and medial side of the forearm were taken after informed consent. Results: Chi-square test showed significant changes in pigmentation pattern and hair pattern on the lateral side of the forearm among subjects who had sun exposure for more than half an hour which was not found on the medial side. Conclusion: Photoaged skin appears coarse with uneven pigmentation. Dermoscopy allows the assessment of subtle morphological features of skin aging. Monitoring skin changes due to sun exposure among our population helps in the early identification of abnormal patterns with sun exposure which needs immediate medical attention. [ABSTRACT FROM AUTHOR]

Colours and associated patterns are probably some of the most obvious phenotypic traits in animals and reef teleost fishes are often cited as a textbook example for illustrating this type of diversity. Even if it is well established that colour patterns play a central role in the ecology and evolution of reef fishes, we still lack the necessary toolkits to fully grasp the mechanisms driving the diversification of this obvious phenotypic trait. On the one hand, genotyping power seems now limitless thanks to current DNA sequencing technologies. Today, entire genomes of fishes can be easily produced for large sets of species. On the other hand, the description of colour patterns and the quantification of their variation across reef fishes might be highly challenging. In a cover manuscript in this issue of Molecular Ecology, Coulmance et al. (2023) introduced an innovative approach for extracting and quantifying the major colour pattern elements present in the hamlets (Hypoplectrus spp., Serranidae), a recent reef fish radiation from the Caribbean. Then, they intelligently used the quantified colour pattern variation as a phenotypic trait for a genome‐wide association study (GWAS). Interestingly, using a method that required no a priori knowledge, they were able to recover well‐established marks (e.g., vertical bars) and to highlight less expected colour pattern elements (e.g., dark to light gradient on ventral part as well as caudal and anal fins), which show strong association peaks on linkage group (LG) 12 and 04. Beyond the demonstration of the potential of their new quantitative analysis of colour pattern variation in reef fishes combined with GWAS, their findings offer new perspectives on our understanding of the intrinsic and extrinsic factors generating this outstanding diversity of the fish world. [ABSTRACT FROM AUTHOR]

In fruits of cultivars of pepper species Capsicum annuum (Sirenevyi Cub), C. frutescens (Samotsvet) and C. chinense (Pimenta da Neyde), which differ in the pigmentation profile during maturation, the content of anthocyanins and the expression pattern of the structural and regulatory genes of anthocyanin biosynthesis were determined. Anthocyanins were found in the fruit of the Sirenevyi Cub cultivar as well as in the peel and pulp of Samotsvet and Pimenta da Neyde cultivars. In the peel of the fruits of all three analyzed cultivars, the levels of expression of structural genes for the biosynthesis of anthocyanins are two or more times higher than in the pulp. In cv. Samotsvet and Pimenta da Neyde, the expression in the pulp of CHS, F3´5´H, DFR, ANS, and UFGT are higher than that of cv. Sirenevyi Cub. The cv. Pimenta da Neyde is characterized by a high expression of structural genes in the pulp and peel of ripe fruit. Expression of transcription factor genes anthocyanin2 (R2R3-MYB) and MYC (bHLH) was detected in the peel of fruits of cv. Sirenevyi Cub as well as in the peel and pulp of fruits of cv. Samotsvet and Pimenta da Neyde at all the analyzed stages of ripening. For all structural genes of the anthocyanin biosynthesis pathway, a high correlation was found (r = 0.54‒0.93) between the expression levels of all anthocyanin biosynthesis structural genes and anthocyanin content in fruits. High correlation (r = 0.88) is also shown for MYC. For the anthocyanin2, correlation (r = 0.85) is present only for cv. Sirenevyi Cub and Pimenta da Neyde but not for cv. Samotsvet. [ABSTRACT FROM AUTHOR]

Summary: The origin of phenotypic novelty is one of the most challenging problems in evolutionary biology. Although genetic regulatory network rewiring or co‐option has been widely recognised as a major contributor, in most cases how such genetic rewiring/co‐option happens is completely unknown.We have studied a novel foliar pigmentation pattern that evolved recently in the monkeyflower species Mimulus verbenaceus. Through genome‐wide association tests using wild‐collected samples, experimental crosses of laboratory inbred lines, gene expression analyses, and functional assays, we identified an anthocyanin‐activating R2R3‐MYB gene, STRIPY, as the causal gene triggering the emergence of the discrete, mediolateral anthocyanin stripe in the M. verbenaceus leaf.Chemical mutagenesis revealed the existence of upstream activators and repressors that form a 'hidden' prepattern along the leaf proximodistal axis, potentiating the unique expression pattern of STRIPY. Population genomics analyses did not reveal signatures of positive selection, indicating that nonadaptive processes may be responsible for the establishment of this novel trait in the wild.This study demonstrates that the origin of phenotypic novelty requires at least two separate phases, potentiation and actualisation. The foliar stripe pattern of M. verbenaceus provides an excellent platform to probe the molecular details of both processes in future studies. [ABSTRACT FROM AUTHOR]

Indo‐Pacific humpback dolphins (Sousa chinensis) inhabit shallow coastal waters of the Indo‐Pacific region including southeast China, with at least 6 putative populations identified to date in Chinese waters. However, the connectivity among these populations has not yet been fully investigated. In the present study, we compared and cross‐matched photographic catalogs of individual dolphins collected to date in the Pearl River Delta region, Leizhou Bay, Sanniang Bay, and waters southwest of Hainan Island, a total of 3158 individuals, and found no re‐sighting of individual dolphins among the 4 study areas. Furthermore, there was a notable difference in the pigmentation pattern displayed by individuals from these 4 regions. We suggest that this may be a phenotypical expression of fine‐scale regional differentiation among humpback dolphin groups, possibly distinct populations. Given the considerable conservation management implications it may carry (e.g. definition of management units), further research is much needed. [ABSTRACT FROM AUTHOR]

Large animal families with unresolved taxonomy are notoriously difficult to handle with respect to their biodiversity, systematics, and evolutionary history. We approach a large and taxonomically unresolved family of freshwater fishes (Nemacheilidae, >600 species) by proposing, on the basis of morphologic data, a species group within the family and study its phylogeny with conclusions regarding its diversity, taxonomy, and biogeographic history. Phylogenetic analyses of two mitochondrial and three nuclear genes of 139 specimens, representing about 46 species (17 candidate species from the proposed species-group, plus 29 comparative species), revealed that the proposed species group does not form a distinct monophyletic lineage, but that the candidate and comparative species mixed in three different lineages. However, the results revealed more than 20% of undescribed species within the ingroup and showed that species do not cluster according to the presently recognised genera. At least one of the genetic clades shows signs of an eastward range expansion during the second half of Miocene from north India via Myanmar into Laos, western China, and western Thailand. We conclude that the approach of picking monophyletic lineages to study biodiversity, systematics, and evolutionary history helps to open the door to large animal families.

Color patterns provide easy access to phenotypic diversity and allow the questioning of the adaptive value of traits or the constraints acting on phenotypic evolution. Reef fish offer a unique opportunity to address such questions because they are ecologically and phylogenetically diverse and have the largest variety of pigment cell types known in vertebrates. In addition to recent development of their genetic resources, reef fish also constitute experimental models that allow the discrimination of ecological, developmental, and evolutionary processes at work. Here, we emphasize how the study of color patterns in reef fish can be integrated in an Eco/Evo/Devo (ecological evolutionary developmental) perspective and we illustrate that such an approach can bring new insights on the evolution of complex phenotypes. Highlights Organisms live in continuously changing environments. Eco/Evo/Devo aims to uncover the rules that underlie the interactions between the environment, genes, and development of an organism. Color patterns have a clear ecological and behavioral significance, with a wide range of functions in animals and in teleosts in particular. Study of model species such as zebrafish allows the understanding of the developmental mechanisms underlying phenotypic evolution. Changes in expression of key molecular factors coupled with changes in cell–cell interactions can lead to color pattern diversification during evolution. Recent studies about color patterns in reef fishes emphasize the need to address such questions in this group in an Eco/Evo/devo perspective, integrating proximate causation and ultimate causation. [ABSTRACT FROM AUTHOR]

This study was conducted to examine morphometric and meristic characteristics alongside pigmentation patterns of bream larvae, Abramis brama orientalis, in four stages of larval development. Morphological characters including total length (TL), standard length (SL), notochord length (NL), head length (HL), head depth (HD), eye diameter (ED) and mouth width (MW) were examined from hatching time through 30 days after hatching (DAH). The results showed morphometric variations in the different larval stages. Growth and development of fins occurred mainly at the Post Flexion stage with the completion of caudal fin at 9 mm TL and pelvic fin at 13.33 mm TL. At all larval stages, the highest concentration of pigments was seen on dorsal, ventral and somewhat on the lateral sides of body in descending order. The highest density of melanophores at larvae yolk sac stage was observed on the yolk sac and the back of head zone, while at preflexion and flexion stages melanophores were dominant on the back of head and on the skin folds which resulted from yolk absorption. At post flexion stage, high density of melanophores was found on the back of the head, bases of fins and caudal fin, while less concentrations of these cells were evident on the lateral sides of fish' body. In conclusion, a clear change in the growth and main morphological characters were observed in postflexion stage. This may be due to the main development of fins, which would suggest enhanced swimming capabilities and also prey capture efficiencies.

The pigmentation patterns of Indo-Pacific humpback dolphins have not been well studied throughout most of the species’ range. In the present study, both the subjective scoring method and a newly developed quantified scoring method were employed to evaluate the spotting intensity of 137 humpback dolphin individuals from the Xiamen and Beibu Gulf putative populations, including the Dafengjiang-Nanliujiang River Estuary (DRE) and Shatian-Caotan (SC) communities. Both scoring methods indicated that spotting intensity on the dorsal fin was lower than that on the body of humpback dolphins in all 3 groups. The SC and DRE humpback dolphins had significantly greater dorsal fin, body spotting intensity, and greater differences between spotting on the dorsal fin and body than Xiamen dolphins, while no differences were found between SC and DRE. The pigmentation variation is related to age class, young dolphins have more spotting density than adults, and young and adults showed similar geographical variation as above. The present paper, in combination with previous research, clarifies the general pattern of pigmentation for Chinese humpback dolphins. Eastern Taiwan Strait and Pearl River Estuary populations represent 2 extreme patterns of pigmentation, while the Xiamen population, SC community, and DRE community seem to be intermediate. The results suggest that these groups should be viewed as demographically distinct forms. 在大多数分布区内，中华白海豚的色素沉着模式尚未得到很好的研究。本研究应用两种方法：前人应用的主观评分法和新开发的数字化评分法，来评估厦门、南流江-大风江河口（DRE），和沙田-草潭（SC）群体中137头中华白海豚个体的斑点密度。两种评分方法均表明， 3个群的中华白海豚背鳍的斑点密度低于身体的斑点强度。SC和DRE中华白海豚的背鳍斑点强度、身体斑点强度，和背鳍和身体上的斑点差值，均显著高于厦门中华白海豚，而SC和DRE之间没有显著差异。色素沉着与年龄相关，我们的研究表明年轻和成年个体呈现出与上述相似的结果。本文结合前人的研究，阐明了中国水域内中华白海豚色素沉着的普遍规律：东台湾海峡和珠江河口的种群分别代表了两种极端的色素沉着模式，而厦门种群，北部湾种群（包括SC社群和DRE社群）代表中间形式，这些群体是统计学显著不同的存在类型。 [ABSTRACT FROM AUTHOR]

Anthocyanin pigments have become a model trait for evolutionary ecology as they often provide adaptive benefits for plants. Anthocyanins have been traditionally quantified biochemically or more recently using spectral reflectance. However, both methods require destructive sampling and can be labor intensive and challenging with small samples. Recent advances in digital photography and image processing make it the method of choice for measuring color in the wild. Here, we use digital images as a quick, noninvasive method to estimate relative anthocyanin concentrations in species exhibiting color variation. Using a consumer-level digital camera and a free image processing toolbox, we extracted RGB values from digital images to generate color indices. We tested petals, stems, pedicels, and calyces of six species, which contain different types of anthocyanin pigments and exhibit different pigmentation patterns. Color indices were assessed by their correlation to biochemically determined anthocyanin concentrations. For comparison, we also calculated color indices from spectral reflectance and tested the correlation with anthocyanin concentration. Indices perform differently depending on the nature of the color variation. For both digital images and spectral reflectance, the most accurate estimates of anthocyanin concentration emerge from anthocyanin content-chroma ratio, anthocyanin content-chroma basic, and strength of green indices. Color indices derived from both digital images and spectral reflectance strongly correlate with biochemically determined anthocyanin concentration; however, the estimates from digital images performed better than spectral reflectance in terms of r2 and normalized root-mean-square error. This was particularly noticeable in a species with striped petals, but in the case of striped calyces, both methods showed a comparable relationship with anthocyanin concentration. Using digital images brings new opportunities to accurately quantify the anthocyanin concentrations in both floral and vegetative tissues. This method is efficient, completely noninvasive, applicable to both uniform and patterned color, and works with samples of any size. [ABSTRACT FROM AUTHOR]

The reaction-diffusion model presented by Alan Turing has recently been supported by experimental data and accepted by most biologists. However, scientists have recognized shortcomings when the model is used as the working hypothesis in biological experiments, particularly in studies in which the underlying molecular network is not fully understood. To address some such problems, this report proposes a new version of the Turing model. This alternative model is not represented by partial differential equations, but rather by the shape of an activation-inhibition kernel. Therefore, it is named the kernel-based Turing model (KT model). Simulation of the KT model with kernels of various shapes showed that it can generate all standard variations of the stable 2D patterns (spot, stripes and network), as well as some complex patterns that are difficult to generate with conventional mathematical models. The KT model can be used even when the detailed mechanism is poorly known, as the interaction kernel can often be detected by a simple experiment and the KT model simulation can be performed based on that experimental data. These properties of the KT model complement the shortcomings of conventional models and will contribute to the understanding of biological pattern formation. [ABSTRACT FROM AUTHOR]

Sexual signals often compromise camouflage because of their conspicuousness. Pigmentation patterns, on the contrary, aid in camouflage. It was hypothesized that a particular type of pattern—barred plumage in birds, whereby pigmented bars extend across feathers—could simultaneously signal individual quality, because disruptions of these patterns should be perceptually salient at close range and help assess plumage condition. Here we show that common waxbills (Estrilda astrild), which have extensive barred plumage, have more regular patterns as adults than as juveniles, and that adult males have more regular patterns than females. Both these differences are indicative of sexual signalling in species with conventional sex roles. More regular barred plumage was related to better body condition in adult males. Colour ornamentation traits were also related to aspects of quality, either the same as barred plumage (body condition) or a different one (good feather development), supporting both the ‘redundant message’ and the ‘multiple message’ hypotheses for the coexistence of multiple sexual signals. Although receiver responses to the regularity of barred plumage were not studied here, research on other species has shown that barred plumage can mediate social interactions. We conclude that using barred plumage as a signal of quality helps circumvent the functional compromise between camouflage and communication.

More than half a century ago, Alan Turing postulated that pigment patterns may arise from a mechanism that could be mathematically modeled based on the diffusion of two substances that interact with each other. Over the past 15 years, the molecular and genetic tools to verify this prediction have become available. Here, we review experimental studies aimed at identifying the mechanism underlying pigment pattern formation in zebrafish. Extensive molecular genetic studies in this model organism have revealed the interactions between the pigment cells that are responsible for the patterns. The mechanism discovered is substantially different from that predicted by the mathematical model, but it retains the property of ‘local activation and long-range inhibition’, a necessary condition for Turing pattern formation. Although some of the molecular details of pattern formation remain to be elucidated, current evidence confirms that the underlying mechanism is mathematically equivalent to the Turing mechanism. [ABSTRACT FROM AUTHOR]

The darkling beetle, Sternoplax souvorowiana (Reitter) (Coleoptera: Tenebrionidae), is flightless and lives in the Guerbantonggut desert in northwestern China. Its special eggshell structure, day-active habit, large body size, short life cycle, and ease of rearing under laboratory conditions make it an excellent model for advanced studies on desert adaptation. Determining the sex of this beetle is usually complicated by the lack of a discreet, externally visible gender-specific character. To date, dissection has been used for sex identification in this species, whereas a nondestructive means is needed for further studies of sexual dimorphism. Here, a new method based on the difference of the pigmentation pattern on the eighth tergite of each sex is described and illustrated. This method can be quickly learned, is nondestructive, is 100% accurate, and is fast enough for most applications in both the field and the laboratory. Experienced users in our laboratory routinely sex 8–10 beetles per minute. [ABSTRACT FROM AUTHOR]

Gobiidae is the most specious fish family in the world with almost 2 000 species, however only 11% of them have been described for their larval stages. The entire life cycle information is essential to understand the biology and ecology of this important fish group. Previous studies on zooplankton samples from Ensenada de La Paz, México, have shown the presence of several Gobiidae larvae and juveniles which were identified as Evermania zosterura. The main objective of this work was to describe the larval stages of this species, widely distributed in the Eastern tropical Pacific. The development of E. zosterura larvae was described based on 66 specimens. A total of 53 specimens were used to describe morphometrics and pigmentation patterns, while 13 specimens were cleared and stained, to obtain meristic characteristics. Cleared specimens had 30 to 31 total vertebrae; dorsal-fin elements: Iv; I, 13-14, anal-fin elements: I, 13-14, and most had pterygiophore formula 4-111100. The combination of these characteristics confirmed these specimens as E. zosterura. The pigment pattern is similar throughout ontogeny. Larvae are characterized by having three to five dendritic melanophores along the post-anal ventral margin, four to nine smaller melanophores along the ventral margin between the isthmus and anus, and one on the midpoint of the dorsal margin of the tail. There is one small pigment spot on the angle of the jaw, and other on the tip of lower lip. There is an elongated internal pigment under the notochord, between the head and gas bladder. Notochord flexion starts near 3.5mm BL and ends at 4.6mm BL; transformation to the juvenile stage is at about 13.6mm BL. Our conclusion is that the most useful characters to distinguish this species early-larval stages from those of similar species in the area, are the number of myomeres, the large melanophores (approximately uniformly in size) on the post anal ventral margin, and the elongate internal pigment under the notochord, anterior to the gas bladder. [ABSTRACT FROM AUTHOR]

Fish biodiversity of aquatic ecosystems is highly threatened by different economic activities driven by human populations, and its description is increasingly a priority. For the Cauca-Magdalena River system we have described 14 species, and the purpose of this paper was to describe three new species belonging to the same genus Hemibrycon from the Nare and Guatapé River drainages of the middle Magdalena River, Colombia. The description was based on a series of 200 specimens, and the use of morphometric, meristic and osteological characters, as well as fish distribution and morphogeometric analytical methods. We have found that Hemibrycon fasciatus n. sp. (n=54) differs from other species of Hemibrycon (that also have a vertical humeral spot) in having: melanophores outlining the posterior margins of the scales along sides of body; humeral spot extending onto posterior margin of opercle; a dark lateral stripe, formed by deep pigment that is continuous with the peduncular spot; the toothed portion of the maxilla not reaching the dorsal margin of the dentary (vs. toothed portion of maxilla extending beyond dorsal margin of dentary); all maxillary teeth tricuspid (vs. some unicuspid teeth present on maxilla). H. cardalensis n. sp. (n=64) differs in having: a vertically elongate humeral spot that extends one or two scales below the lateral line canal. H. cardalensis n. sp. differs from all congeners in having the pigment of the caudal spot restricted to the ventral half of the caudal peduncle, and in having melanophores around the anterior scales of the lateral line. Hemibrycon antioquiae n. sp. (n=82) differs in having a circular humeral spot. It differs from the other species with a circular humeral spot, like H. mikrostiktos, in having a projection of disperse melanophores extending from the dorsal margin of the humeral spot to below the lateral stripe. Habitat data and environmental impacts caused by the construction of reservoirs for hydroelectric projects and other threats in the area are included, as well as a key to all species Hemibrycon present in the Magdalena River Basin. The synonymy of H. pautensis with H. polyodon is discussed and H. pautensis is revalidated. [ABSTRACT FROM AUTHOR]

Marbled salamanders (Ambystoma opacum) have individually variable dorsal pigmentation patterns. But it is unclear whether or not dorsal pigmentation is associated with variables such as body size and sex. In this study, we test the hypothesis that the body size variables and sex are important predictors of the coverage of dorsal body white pigmentation in adult marbled salamanders. We evaluate the degree of sexual dimorphism in several body traits, including the dorsal body white pigmentation, using univariate and multivariate methods, and analyze the sex-related difference in pigmentation asymmetry. The General Linear Model (GLM) predicts a significant main effect of sex and a significant interaction between sex and dorsal body area (DBA), influencing the coverage of dorsal body white pigmentation. The interaction effect is greater in males than in females. We show significant sex-related differences in body size and shape. Eight morphometric traits reveal female-biased sexual size dimorphism, while males display a greater coverage of dorsal white pigmentation than females. Prominent female characteristics, compared to males, include a significantly heavier and longer body with a wider trunk, head, neck, shoulder and waist. These sex-specific differences suggest selection for a larger body size in females because of increased maternal reproductive success associated with larger body size. Additionally, females display greater pigmentation asymmetry than males, suggesting a significant sex-related disparity in asymmetric pigmentation. Potential ecological and developmental implications of the observed dimorphism are discussed. To our knowledge, this is the first study demonstrating an association of dorsal white pigmentation with dorsal body area and sex, including a significantly disproportionate pigmentation asymmetry between sexes, in adult marbled salamanders. [ABSTRACT FROM AUTHOR]

Abstract: The pigmentation patterns of ‘Mantianhong’ (Pyrus pyrifolia Nakai) and ‘Cascade’ (Pyrus communis L.) that develop under bagging and postharvest UV-B/visible irradiation conditions were evaluated in this study. The results showed that, unlike ‘Cascade,’ in which almost no anthocyanin was detected, ‘Mantianhong’ developed good red coloration under bagging treatment and postharvest irradiation. The activity of PAL and DFR increased during anthocyanin accumulation. The expression of PpCHS3, PpCHI3, PpUFGT1, and PyMYB10 was up-regulated in ‘Mantianhong’ but not in ‘Cascade’ during both treatments. This suggests that these four genes may be limiting factors for peel coloration in ‘Cascade.’ The expression patterns of gene family members were also different during fruit red coloration, suggesting that different gene family members may have distinct functions during pear development. The results obtained in this study are helpful in understanding the molecular mechanism of anthocyanin accumulation in red pears and can serve as the basis for the development of marker-assisted selection or for anthocyanin metabolic engineering of pears. [Copyright &y& Elsevier]

The species of the genus Notopygos Grube, 1855 are characterized by an ovate body, a prominent caruncle with three lobes, dendritic branchiae, and double dorsal cirri. Twenty-two species belonging to Notopygos have been described, mostly from the Indo-Pacific region. In America, few species are frequently recorded: N. crinita Grube, 1855 from St. Helena Island (Atlantic) and N. ornata Grube and ørsted in Grube 1857 from Costa Rica (Pacific). Notopygos crinita is a widely distributed species in the Western Atlantic with additional reports in the Mediterranean Sea (as a questionable alien species) and in the Pacific Ocean. However, only the genus features have been considered, consequently some records could be misidentifications. During a revision of materials from collections and the barcode project, 'Mexican Barcode of Life, MEXBOL', we found specimens of N. megalops and an undescribed species from reef zones in the Caribbean; the former had been considered a junior synonym of N. crinita. Herein, N. megalops is reestablished and N. caribea sp. n. is described. A morphological and DNA barcode approach was used to explain the records of N. ornata in the Atlantic and to show the differences with the new species, since both species share features such as complex pigmentation patterns, and circular projections in the median lobe of the caruncle. [ABSTRACT FROM AUTHOR]

Selection for efficient conversion of solar radiation to body heat has favored the evolution of dark coloration in many ectotherms. The thermal melanism hypothesis posits that dark coloration is beneficial under conditions of low ambient temperatures because it results in faster heating rates and higher body temperatures. Fast heating rates, however, may come at a cost of overheating unless compensated for by thermal physiology or behaviour. Pygmy grasshopper (Orthoptera, Tetrigidae) populations that inhabit fire-ravaged areas characterized by blackened backgrounds and hot surface temperatures due to high absorbance of solar radiation show an increased frequency of black phenotypes. I raised the progeny of wild-captured Tetrix undulata in cold and hot temperatures and used data on color patterns and survival in a greenhouse to examine whether a cold thermal environment triggered the development of melanic coloration or differently affected survival of melanic versus non-melanic individuals. My results indicate that melanism was not influenced by rearing temperature but by genes or epigenetic maternal effects. Temperature also did not affect survival. However, melanic individuals produced by melanic mothers survived longer than melanic individuals produced by non- melanic mothers, whereas non-melanic individuals produced by non-black mothers survived longer than melanic individuals produced by non-black mothers. This suggests a mismatch between color and physiology in offspring belonging to a different color morph than their mother. Future investigations into the evolution of melanism should consider conflicting selection pressures on thermal capacity and camouflage as well as the influence of correlated responses to selection on traits associated with coloration. [ABSTRACT FROM AUTHOR]

Two morphological characters were examined in 4099 anguillid glass eels sampled in four south-western Indian Ocean islands, and resulting identifications were tested using genetic analysis. Distance between the origin of the dorsal and anal fins as related to total length and tail and caudal fin pigmentation enabled formulation of a useful field identification key, which was able to discriminate 4036 glass eels of the regional species Anguilla bicolor bicolor, Anguilla marmorata and Anguilla mossambica, and excluded the occurrence of Anguilla nebulosa labiata in the sample. [ABSTRACT FROM AUTHOR]

A major driving force behind the evolution of species-specific traits and novel structures is alterations in gene regulatory networks (GRNs). Comprehending evolution therefore requires an understanding of the nature of changes in GRN structure and the responsible mechanisms. Here, we review two insect pigmentation GRNs in order to examine common themes in GRN evolution and to reveal some of the challenges associated with investigating changes in GRNs across different evolutionary distances at the molecular level. The pigmentation GRN in Drosophila melanogaster and other drosophilids is a well-defined network for which studies from closely related species illuminate the different ways co-option of regulators can occur. The pigmentation GRN for butterflies of the Heliconius species group is less fully detailed but it is emerging as a useful model for exploring important questions about redundancy and modularity in cis-regulatory systems. Both GRNs serve to highlight the ways in which redeployment of trans-acting factors can lead to GRN rewiring and network co-option. To gain insight into GRN evolution, we discuss the importance of defining GRN architecture at multiple levels both within and between species and of utilizing a range of complementary approaches. [ABSTRACT FROM AUTHOR]

Simple Summary: Since large animal families with unresolved taxonomy are difficult to study, it is better to focus on smaller units. In the present study, we test if we can define a restricted group of species within a large and unsorted fish family (Nemacheilidae). In the beginning, we selected 17 candidate species that share a rare and specific pigmentation pattern, and 29 comparative species with a different pattern. We studied their relationships and the ages of pedigree branches using molecular genetic markers. It turned out that the candidate and comparative species are intermixed in two main groups, meaning that the specific pigmentation pattern is not diagnostic. However, the genetic lineages themselves are smaller units within the large family Nemacheilidae and can be used for further studies. For example, one group revealed its evolutionary history: it expanded 12 million years ago from India into Myanmar and later further to Thailand, Laos, and China. They also revealed more than 20% of undescribed species, a very high rate in vertebrates. Our results show that species groups can be a helpful tool to approach large and unsorted animal units. This finding offers species groups as a new tool for future studies exploring the diversity of life on earth. Large animal families with unresolved taxonomy are notoriously difficult to handle with respect to their biodiversity, systematics, and evolutionary history. We approach a large and taxonomically unresolved family of freshwater fishes (Nemacheilidae, >600 species) by proposing, on the basis of morphologic data, a species group within the family and study its phylogeny with conclusions regarding its diversity, taxonomy, and biogeographic history. Phylogenetic analyses of two mitochondrial and three nuclear genes of 139 specimens, representing about 46 species (17 candidate species from the proposed species-group, plus 29 comparative species), revealed that the proposed species group does not form a distinct monophyletic lineage, but that the candidate and comparative species mixed in three different lineages. However, the results revealed more than 20% of undescribed species within the ingroup and showed that species do not cluster according to the presently recognised genera. At least one of the genetic clades shows signs of an eastward range expansion during the second half of Miocene from north India via Myanmar into Laos, western China, and western Thailand. We conclude that the approach of picking monophyletic lineages to study biodiversity, systematics, and evolutionary history helps to open the door to large animal families. [ABSTRACT FROM AUTHOR]

The hesionid polychaete Hesione reticulata von Marenzeller, 1879 was described from Enoshima Island, Japan and has been recorded also from the Red Sea. Depending on researchers, it has been regarded as either a distinct species or synonymous with older established ones. The type specimen has been lost. In order to clarify its taxonomic status, Hesione reticulata is herein redescribed, illustrated, and a neotype is proposed based on recent material collected near the type locality. The diagnostic features include the presence of several dorsal, discontinuous longitudinal bands, interrupted by pale segmental spots; prostomium with tiny antennae; a tuberculated dorsal integument; acicular lobes double; and neurochaetal blades with guards approaching the distal tooth. The dorsal color pattern in life enables a clear distinction from similar species such as Hesione intertexta Grube, 1878 amongst others. Mitochondrial COI barcoding sequences are deposited in the DNA Data Bank of Japan. A key to Hesione species from Japan is also included.

Sexual signals often compromise camouflage because of their conspicuousness. Pigmentation patterns, on the contrary, aid in camouflage. It was hypothesized that a particular type of pattern-barred plumage in birds, whereby pigmented bars extend across feathers-could simultaneously signal individual quality, because disruptions of these patterns should be perceptually salient at close range and help assess plumage condition. Here we show that common waxbills (Estrilda astrild), which have extensive barred plumage, have more regular patterns as adults than as juveniles, and that adult males have more regular patterns than females. Both these differences are indicative of sexual signalling in species with conventional sex roles. More regular barred plumage was related to better body condition in adult males. Colour ornamentation traits were also related to aspects of quality, either the same as barred plumage (body condition) or a different one (good feather development), supporting both the 'redundant message' and the 'multiple message' hypotheses for the coexistence of multiple sexual signals. Although receiver responses to the regularity of barred plumage were not studied here, research on other species has shown that barred plumage can mediate social interactions. We conclude that using barred plumage as a signal of quality helps circumvent the functional compromise between camouflage and communication.

The darkling beetle, Sternoplax souvorowiana (Reitter) (Coleoptera: Tenebrionidae), is flightless and lives in the Guerbantonggut desert in northwestern China. Its special eggshell structure, day-active habit, large body size, short life cycle, and ease of rearing under laboratory conditions make it an excellent model for advanced studies on desert adaptation. Determining the sex of this beetle is usually complicated by the lack of a discreet, externally visible gender-specific character. To date, dissection has been used for sex identification in this species, whereas a nondestructive means is needed for further studies of sexual dimorphism. Here, a new method based on the difference of the pigmentation pattern on the eighth tergite of each sex is described and illustrated. This method can be quickly learned, is nondestructive, is 100% accurate, and is fast enough for most applications in both the field and the laboratory. Experienced users in our laboratory routinely sex 8-10 beetles per minute., (© The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America.)

The natural bicolor floral traits of the horticultural petunia ( Petunia hybrida) cultivars Picotee and Star are caused by the spatial repression of the chalcone synthase A ( CHS-A) gene, which encodes an anthocyanin biosynthetic enzyme. Here we show that Picotee and Star petunias carry the same short interfering RNA (siRNA)-producing locus, consisting of two intact CHS-A copies, PhCHS-A1 and PhCHS-A2, in a tandem head-to-tail orientation. The precursor CHS mRNAs are transcribed from the two CHS-A copies throughout the bicolored petals, but the mature CHS mRNAs are not found in the white tissues. An analysis of small RNAs revealed the accumulation of siRNAs of 21 nucleotides that originated from the exon 2 region of both CHS-A copies. This accumulation is closely correlated with the disappearance of the CHS mRNAs, indicating that the bicolor floral phenotype is caused by the spatially regulated post-transcriptional silencing of both CHS-A genes. Linkage between the tandemly arranged CHS-A allele and the bicolor floral trait indicates that the CHS-A allele is a necessary factor to confer the trait. We suppose that the spatially regulated production of siRNAs in Picotee and Star flowers is triggered by another putative regulatory locus, and that the silencing mechanism in this case may be different from other known mechanisms of post-transcriptional gene silencing in plants. A sequence analysis of wild Petunia species indicated that these tandem CHS-A genes originated from Petunia integrifolia and/or Petunia inflata, the parental species of P. hybrida, as a result of a chromosomal rearrangement rather than a gene duplication event. [ABSTRACT FROM AUTHOR]