Color Evolution Research Articles

Rapid assessment of acetophenone using an anti-interfering triple-emission Ln3+-functionalized HOF@MOF sensor

The development of high-performance sensors for rapidly detecting acetylacetone (AP) in water samples is necessary because its release into the environment can result in many vital problems for human health and environment. Herein, we first designed a hybrid by integrating HOF with ZIF-8 through a sequential growth strategy. By separately introducing blue-emitting SiQDs and green- and red-emitting Tb3+ and Eu3+ into ZIF-8 and HOF, the resultant ZIF-8@SiQDs@HOF@Eu3+@Tb3+ comprised three emission peaks at 484, 545 and 620 nm, all of which could be employed as switch-off responsive peaks to low concentrations of AP with a detection limit of 0.79 ppm. However, in environments with high concentrations of AP, a turn-on signal at 484 nm was observed. Thereupon, the ratiometric fluorescence intensity of the ternary emission varied within different concentration ranges, accompanied by the fluorescence color evolution from red to salmon to plum to purple to final blue. Moreover, a portable sensing film was fabricated for rapid warning, sensitive and visual determination of AP in complicated environments. Therefore, this triple-emission sensor with wide color variations and strong anti-interference advantages could promote further research to improve the selectivity, sensitivity and inherent self-correction of multimodal fluorescence detection and the ease of sensing operation.

Size differences among canaries, goldfinches and allies may explain correlated evolution of song and colour.

Sexual signals such as colour ornamentation and birdsong evolve independently of each other in some clades, and in others they evolve positively or negatively correlated. We rarely know why correlated evolution does or does not occur. Here, we show positively correlated evolution between plumage colour and song motor performance among canaries, goldfinches and allies, associated with species differences in body size. When controlling for body size, the pattern of correlated evolution between song performance and colour disappeared. Syllable diversity was not as strongly associated with size, and did not evolve in a correlated manner with colour. We argue that correlated evolution between song and colour was mediated by large size limiting song motor performance, likely due to constraints on the speed of moving heavier bills, and by larger species having less saturated plumage colour, possibly due to life-history traits of larger birds (e.g. longevity, stable pairs) contributing to weaker sexual selection. Results are consistent with the hypothesis that correlated evolution between sexual signals is influenced by how, in a clade, selective pressures and constraints affecting each type of signal happen to be co-distributed across species. Such contingency helps explain the diversity in clade-specific patterns of correlated evolution between sexual signals.

Transitions between colour mechanisms affect speciation dynamics and range distributions of birds.

Several ecogeographical 'rules' have been proposed to explain colour variation at broad spatial and phylogenetic scales but these rarely consider whether colours are based on pigments or structural colours. However, mechanism can have profound effects on the function and evolution of colours. Here, we combine geographic information, climate data and colour mechanism at broad phylogenetic (9,409 species) and spatial scales (global) to determine how transitions between pigmentary and structural colours influence speciation dynamics and range distributions in birds. Among structurally coloured species, we find that rapid dispersal into tropical regions drove the accumulation of iridescent species, whereas the build-up of non-iridescent species in the tropics was driven by a combination of dispersal and faster in situ evolution in the tropics. These results could be explained by pleiotropic links between colouration and dispersal behaviour or ecological factors influencing colonization success. These data elucidate geographic patterns of colouration at a global scale and provide testable hypotheses for future work on birds and other animals with structural colours.

Physicochemical, antioxidant activity, and sensory properties of grape juice-herbs extract based isotonic beverages

The aim of this work was to develop isotonic drinks free of chemical additives and based on grape juice as a source of carbohydrates, pigments and rich in antioxidants, mixed with herb and spice extracts to improve the taste of the drinks. The color evolution, pH and acidity, sugar content, anthocyanin content, antioxidant activity and sensory properties were analyzed. The results of color evolution demonstrated an increase in color intensity in all samples over four weeks. The determination of anthocyanins revealed the presence of non-acylated and acylated anthocyanins, with malvidin pigments predominating (71.75–73.05%). Antioxidant activity values ranged from 3.97 to 4.92 μmol TE/mL and were positively correlated with anthocyanin content, however anthocyanins were negatively correlated with pH. Sensory evaluation showed that the combination of grape juice with herb and spice extracts promoted the use of natural sources to enrich sports drinks with antioxidants and improve their sensory profile.

Colour pattern diversity and evolution in Oriental velvet ants (Hymenoptera: Aculeata: Mutillidae)

Abstract The Mutillidae (Hymenoptera: Aculeata) are a family of solitary ectoparasitoid wasps, famous for their sting and conspicuous coloration. The occurrence of Müllerian mimicry complexes has been demonstrated in both Africa and North America. Müllerian mimicry is the resemblance between several harmful species, advertising their defence to would-be predators by sharing a conspicuous colour pattern. Various colour patterns are known to occur in Oriental (Asian) velvet ants, but potential Müllerian mimicry complexes have not yet been inferred. We analysed the coloration of the females of 283 Oriental velvet ant species (52 genera), characterized by 12 phenotypic traits, and we identified shared colour patterns. Morphological differences between groups were tested using non-metric multidimensional scaling and permutational multivariate analysis of variance. We also inferred the geographical range of these colour patterns, and we investigated whether the shared patterns are the result of convergent evolution or common ancestry. We identified six distinct shared colour patterns, of which four can be associated with Müllerian mimicry. We also studied the position and shape of metasomal markings, and we found no association with mimicry rings. Our results improve the understanding of colour evolution in Oriental velvet ants and extend the previously described Müllerian mimicry complex to the south Asiatic landmass.

Bi3+/Eu3+ Co‐Activated Multimode Anti‐Counterfeiting Material with White Light Emission and Orange‐Yellow Persistent Luminescence

AbstractTraditional anti‐counterfeiting luminescent phosphors are usually composed of single‐mode photoluminescence materials, which greatly limits the security of encryption by its static fluorescent pattern. Herein, multi‐mode luminescence properties are achieved including fluorescence and persistent luminescence (PersL) within single host by co‐doping Bi3+ and Eu3+ in CaNaSb2O6F (CNSOF). A tunable emission is observed from blue (Bi3+, 3P1→1S0) to white and then to orange‐yellow (Eu3+, 5D1→7F2 and 5D0→7F0, 1, 2, 3, 4) as the excitation schemes, environment temperatures and doping level are modulated. Impressively, the blue emission attributed to the Bi3+ rapidly disappears after stopping the excitation light irradiation, and only the intense orange‐yellow PersL produced by Eu3+ can be observed. And a possible model for the energy transfer and PersL mechanism is proposed by the investigation crystal structure and photoluminescence/PersL. A schematic of security logo and digital information encryption is demonstrated using the prepared samples, which shows the dynamic evolution of the emission color and PersL brightness. The excellent property of multiple color outputs, different decay processes, and external field stimulation modes (including low energy light, thermal, and mechanical stimuli) present in CNSOF:Bi3+, Eu3+ provides a fast, low‐cost, and effective method for advanced anti‐counterfeiting and information encryption applications.

Correlated evolution of conspicuous colouration and burrowing in crayfish.

Conspicuous colours have fascinated biologists for centuries, leading to research on the evolution and functional significance of colour traits. In many cases, research suggests that conspicuous colours are adaptive and serve a function in sexual or aposematic signalling. In other cases, a lack of evidence for the adaptive value of conspicuous colours garners interest from biologists, such as when organisms that live underground and are rarely exposed to the surface are nevertheless colourful. Here, we use phylogenetic comparative methods to investigate colour evolution throughout freshwater crayfishes that vary in burrowing ability. Within the taxa we analysed, conspicuous colours have evolved independently over 50 times, and these colours are more common in semi-terrestrial crayfishes that construct extensive burrows. The intuitive but not evolutionarily justified assumption when presented with these results is to assume that these colours are adaptive. But contrary to this intuition, we discuss the hypothesis that colouration in crayfish is neutral. Supporting these ideas, the small population sizes and reduced gene flow within semi-terrestrial burrowing crayfishes may lead to the fixation of colour-phenotype mutations. Overall, our work brings into question the traditional view of animal colouration as a perfectly adapted phenotype.

Melanin-based color variation in response to changing climates in snakes.

Melanism, the process of heavier melanin deposition, can interact with climate variation at both micro and macro scales, ultimately influencing color evolution in organisms. While the ecological processes regulating melanin production in relation to climate have been extensively studied, intraspecific variations of melanism are seldom considered. Such scientific gap hampers our understanding of how species adapt to rapidly changing climates. For example, dark coloration may lead to higher heat absorption and be advantageous in cool climates, but also in hot environments as a UV or antimicrobial protection mechanism. To disentangle such opposing predictions, here we examined the effect of climate on shaping melanism variation in 150 barred grass snakes (Natrix helvetica) and 383 green whip snakes (Hierophis viridiflavus) across Italy. By utilizing melanistic morphs (charcoal and picturata in N. helvetica, charcoal and abundistic in H. viridiflavus) and compiling observations from 2002 to 2021, we predicted that charcoal morphs in H. viridiflavus would optimize heat absorption in cold environments, while offering protection from excessive UV radiation in N. helvetica within warm habitats; whereas picturata and abundistic morphs would thrive in humid environments, which naturally have a denser vegetation and wetter substrates producing darker ambient light, thus providing concealment advantages. While picturata and abundistic morphs did not align with our initial humidity expectations, the charcoal morph in N. helvetica is associated with UV environments, suggesting protection mechanisms against damaging solar radiation. H. viridiflavus is associated with high precipitations, which might offer antimicrobial protection. Overall, our results provide insights into the correlations between melanin-based color morphs and climate variables in snake populations. While suggestive of potential adaptive responses, future research should delve deeper into the underlying mechanisms regulating this relationship.

Claw coloration in the fiddler crab Leptuca uruguayensis has no correlation with male quality

Abstract Sexual selection is thought to play a major role in the evolution of color due to the correlation between a signaler’s physiological state and the displayed color. As such, researchers often investigate how color correlates to the quality of the signaler. However, research on the relationship between color and individual quality is often taxonomically limited and researchers typically investigate how color phenotypes relate to one index of quality, such as a linear measure of body size. Here, we investigated the relationship among body size, claw size, claw muscle mass, lipid content, and the color of the claw in male fiddler crabs (Leptuca uruguayensis) which wield an exaggerated claw that varies in color from brown to red. We hypothesized that if the color was correlated to one or more indices of male quality, the color displayed on the claws of male L. uruguayensis could be under sexual selection. We found L. uruguayensis claw color varies substantially among the individuals we photographed. However, we did not find a correlation between claw color and indices of quality; neither brightness nor hue correlated to the indices of quality we measured. Our findings suggest that claw color in L. uruguayensis is unlikely to have evolved to signal quality, but may instead function as a species identity or as a non-indicator sexual signal.

Ecological drivers of ultraviolet colour evolution in snakes

Ultraviolet (UV) colour patterns invisible to humans are widespread in nature. However, research bias favouring species with conspicuous colours under sexual selection can limit our assessment of other ecological drivers of UV colour, like interactions between predators and prey. Here we demonstrate widespread UV colouration across Western Hemisphere snakes and find stronger support for a predator defence function than for reproduction. We find that UV colouration has evolved repeatedly in species with ecologies most sensitive to bird predation, with no sexual dichromatism at any life stage. By modelling visual systems of potential predators, we find that snake conspicuousness correlates with UV colouration and predator cone number, providing a plausible mechanism for selection. Our results suggest that UV reflectance should not be assumed absent in “cryptically coloured” animals, as signalling beyond human visual capacities may be a key outcome of species interactions in many taxa for which UV colour is likely underreported.

Mapping and annotating genomic loci to prioritize genes and implicate distinct polygenic adaptations for skin color

Evidence for adaptation of human skin color to regional ultraviolet radiation suggests shared and distinct genetic variants across populations. However, skin color evolution and genetics in East Asians are understudied. We quantified skin color in 48,433 East Asians using image analysis and identified associated genetic variants and potential causal genes for skin color as well as their polygenic interplay with sun exposure. This genome-wide association study (GWAS) identified 12 known and 11 previously unreported loci and SNP-based heritability was 23–24%. Potential causal genes were determined through the identification of nonsynonymous variants, colocalization with gene expression in skin tissues, and expression levels in melanocytes. Genomic loci associated with pigmentation in East Asians substantially diverged from European populations, and we detected signatures of polygenic adaptation. This large GWAS for objectively quantified skin color in an East Asian population improves understanding of the genetic architecture and polygenic adaptation of skin color and prioritizes potential causal genes.

Oxidative Evolution of Different Model Rosé Wines Affected by Distinct Anthocyanin and Tannin Contents

The quality of rosé wines significantly depends on their phenolic composition, particularly tannins, anthocyanins, and their derivatives, which determine the perceived color of these products and their color evolution throughout the storage and shelf-life periods. This study investigated the impact of phenolic content on the oxidation and color evolution of five different model rosé wines obtained by blending a fixed amount of grape tannins with varying concentrations of oenocyanin to modulate their respective ratio and color intensity. The solutions were monitored for color and pigment changes promoted by oxidation in a Fenton-like environment. The findings revealed a potential correlation between the initial phenolic concentration and the different degrees of oxidation within each solution, resulting in significant variations in CIELAB data. Overall, all solutions exhibited a substantial decrease in redness, with losses ranging from 23% in the darkest solution to 43% in the lightest one compared to their initial levels. Additionally, their color profiles shifted toward yellow hues, up to triple the original value, indicating the degradation of the pigments responsible for the characteristic rosé color. Greater amounts of anthocyanins preserved higher Fe(II) concentrations over time, suggesting the antioxidant role of these compounds. The whole dataset also permitted the evaluation of the different oxidation susceptibilities of individual anthocyanins, among which derived pigments, such as vitisins, proved to be notably more stable than native pigments, particularly delphinidin and petunidin.

Preparation of Choco Dates Bar

Abstract: We aimed to produce dates bar by using of dates, standard procedure we adopted for preparing the Choco dates bar. However, in this study, product was devoid of any sweet additives, as dates are rich in natural sugar. Various analysis (proximate composition moisture andAsh, color, texture profile and sensory quality evolution) Were performed to evaluate the overallvirtues of dates-basedbarto be rich in protein, Fat and carbohydrates with good energy values. TheRadical was observed in bars compared to raw dates. Texture wise, product had high factor- ability, indicating easy to bite and chew nature thus rendering it suitable for elderly people and small children. result of sensory quality evolution indicated dates have evolutes potential to be converted into bars. Result generated in this study suggests date-based bars maybe expected to fulfill the requirement of heart conscious consumers. it is anticipated that the ‘CHOCO DATESBAR' attract better marketability at the international level.

Synchrotron radiation excited luminescence of Eu, Er, and Tm codoped β-Ga2O3 thin film

Ga2O3 thin film with Eu, Er, and Tm codoping was prepared on Si substrate by pulsed laser deposition. The obtained codoping film has a monoclinic Ga2O3 structure identified by X-ray diffraction and Raman measurements. The excitation wavelength-dependent photoluminescence measurements were performed using synchrotron radiation sources with photon energies both below and above bandgap. Moreover, temperature-dependent PL measurements were carried out from 30 to 300 K to systematically investigate the PL characteristics of codoped Eu3+, Er3+, Tm3+ ions in the Ga2O3 film. Typical luminescent bands originating from Eu3+, Er3+, and Tm3+ dopants were concurrently observed in the PL spectra. The codoping film emits a near purple light when it was excited at 30 K, which gradually shifts to the orange region as the temperature rises to 300 K. This color evolution results from different quenching rates of Eu3+, Er3+, and Tm3+ dopants with the increase of temperature. These findings provide a solid foundation for Si-compatible full-color displays using RE doped Ga2O3.

Thermomechanical and physicochemical evolution of meat‐analogue based fried foods

SummaryThis study aimed to get mechanistic insights on the evolution of major quality attributes of meat‐analogue (MA) based batter‐coated fried products. Wheat and rice flour‐based batter systems were used to coat a MA. The products were deep‐fried at 180°C for 4 min in canola oil and their post‐fry quality changes at room environment (RE, 25°C) and under IR‐heating (65 °C) were investigated. Results showed that in addition to moisture‐fat profile, batter coating substantially (P < 0.05) influenced the development of thermal, textural, colour and microstructural traits of MA. Post‐fry colour changes (ΔE value: 3.1 to 10.4) in MA‐based coated product continued under IR‐heating (65 °C). Evolution of the thermal, textural and colour attributes of MA‐based coated products were significantly (P < 0.05) influenced by the formulation of outer batter coatings. Moisture migration occurred from high moisture (ranged from 1.07 to 1.25 g g−1 dry matter) containing core to dry (moisture ranged from 0.15 to 0.59 g g−1 dry matter) crust region of MA‐based coated fried product, where the moisture migration was interlaced with batter formulations. Holding environment and duration substantially (P < 0.05) impacted the textural properties (hardness, brittleness and crispiness) of MA‐based coated fried product. Glass transition temperature (Tg) of coated fried products were ranged between −20.4 to −23.0 °C, that explains quality changes at RE and under IR‐heating. Scanning electron microscopic image analysis (surface openings: 5.7 to 27.31%; fractal dimension: 2.555 to 2.702) revealed the impact of surface microstructure and mass‐transfer modulated textural development in MA‐based coated products. FTIR spectroscopy revealed surface chemical profile in relation to colour evolution of MA‐based fried products. Principal component analysis outcome (PC1: 52.9.% and PC2: 25.8%) revealed varying extent of correlation between studied thermomechanical and physicochemical attributes.

A highly resolved nuclear phylogeny uncovers strong phylogenetic conservatism and correlated evolution of fruit color and size in Solanum L.

Mutualisms between plants and fruit-eating animals were key to the radiation of angiosperms. Still, phylogenetic uncertainties limit our understanding of fleshy-fruit evolution, as in the case of Solanum, a genus with remarkable fleshy-fruit diversity, but with unresolved phylogenetic relationships. We used 1786 nuclear genes from 247 species, including 122 newly generated transcriptomes/genomes, to reconstruct the Solanum phylogeny and examine the tempo and mode of the evolution of fruit color and size. Our analysis resolved the backbone phylogeny of Solanum, providing high support for its clades. Our results pushed back the origin of Solanum to 53.1 million years ago (Ma), with most major clades diverging between 35 and 27 Ma. Evolution of Solanum fruit color and size revealed high levels of trait conservatism, where medium-sized berries that remain green when ripe are the likely ancestral form. Our analyses revealed that fruit size and color are evolutionary correlated, where dull-colored fruits are two times larger than black/purple and red fruits. We conclude that the strong phylogenetic conservatism shown in the color and size of Solanum fruits could limit the influences of fruit-eating animals on fleshy-fruit evolution. Our findings highlight the importance of phylogenetic constraints on the diversification of fleshy-fruit functional traits.

Genome of the endangered eastern quoll (Dasyurus viverrinus) reveals signatures of historical decline and pelage color evolution

The eastern quoll (Dasyurus viverrinus) is an endangered marsupial native to Australia. Since the extirpation of its mainland populations in the 20th century, wild eastern quolls have been restricted to two islands at the southern end of their historical range. Eastern quolls are the subject of captive breeding programs and attempts have been made to re-establish a population in mainland Australia. However, few resources currently exist to guide the genetic management of this species. Here, we generated a reference genome for the eastern quoll with gene annotations supported by multi-tissue transcriptomes. Our assembly is among the most complete marsupial genomes currently available. Using this assembly, we infer the species’ demographic history, identifying potential evidence of a long-term decline beginning in the late Pleistocene. Finally, we identify a deletion at the ASIP locus that likely underpins pelage color differences between the eastern quoll and the closely related Tasmanian devil (Sarcophilus harrisii).

Extraction and characterization of anthocyanin pigments from Iris flowers and metal complex formation

Exploring the chemical processes and factors influencing the stability of the blue color derived from anthocyanins is a crucial objective in agricultural and food chemistry research. The ability of these compounds to bind with metals could potentially stabilize anthocyanins extracted from plant-based foods or enable modifying their hues for application as natural food colorants. This study had two core objectives - first, to extract and identify the major anthocyanin pigments responsible for iris flower coloration. Second, to selectively complex purified iris anthocyanins with aluminum (Al3+) and copper (Cu2+) ions, probing the coordination chemistry underlying synthetic metalloanthocyanin formation. Fresh iris flowers were collected and anthocyanins extracted using an optimized acidic solution. After separation, anthocyanins were complexed with metals Al3+ and Cu2+ at pH 5–6 to understand better the evolution of blue and green colors in anthocyanin-metal chelates. Characterization of anthocyanins and their metal complexes utilized UV–visible spectrometry, colorimetry (L\\* a\\*b\\* values), FTIR spectroscopy, and LC-MS. Metal complexation of anthocyanins exhibited bathochromic shifts of visible absorption maxima from 538 to 584 nm for Al-complex and 538–700 nm for Cu-complex. Color changes were accompanied by decreased lightness (L\\*, from 87 to 81) and color coefficients a\\* (+5.4 to −6.8) and b\\* (−12.2 to −4.8). LC-MS analysis identified five major anthocyanin aglycones: cyanidin (Cyd, m/z 289), delphinidin (Dpd, m/z 305), petunidin (Ptd, m/z 229), malvidin (Mv, m/z 329) and pelargonidin (m/z 273), along with various glycosylated derivatives. This work successfully isolated key iris anthocyanin pigments and elucidated their metal chelation interactions underlying expanded floral color production, bridging knowledge gaps about this underexplored genus.

Rational primary drying temperature for freeze-drying of fermented dairy products

The influence of primary drying temperature on the quality of freeze-dried fermented dairy products was determined experimentally. The objectives of this research were to investigate the freeze-drying characteristics of yogurt, bio-yogurt and curdled milk dried at primary drying temperatures of −40 ± 2 °C; −25 ± 2 °C; −15 ± 2 °C; −10 ± 2 °C and −5 ± 2 °C. The primary drying time and the total drying time of the tested products were determined for each primary drying temperature. The survival rate of lactic acid bacteria, active and titratable acidity, color and sensory quality evolution were also determined. Increasing the temperature of primary drying (p < 0.05) from −40 ± 2 °C to −25 ± 2 °C was observed to lead to the preservation of 75–80% of lactic acid bacteria. A further increase in the primary drying temperature to −15 ± 2 °C and to −10 ± 2 °C leads to a decrease (p < 0.05) of this parameter to 65-70% and 5-35%, respectively. It is noted that an increase in the temperature of primary drying leads to a decrease (p < 0.05) in pH to 3.7-3.8 and an increase (p < 0.05) in the titratable acidity to 93-95°T for yogurt and bio-yogurt and it is up to 85°T for curdled milk. An increase in the primary drying temperature affected the sensory characteristics of the freeze-dried dairy products. The optimal primary drying temperature for yogurt and curdled milk is found to be −25 ± 2 °C, and for bio-yogurt this temperature is −15 ± 2 °C. The application of the optimal primary drying temperature proposed in the industrial practice is expected to lead to significant savings in specific energy costs along with a reduction in the time of drying.

Morphological changes and color development during cookie baking-Kinetic, heat, and mass transfer considerations.

Color and shape are important quality attributes in baked goods, particularly cookies. Composition and processing conditions determine and influence color development and morphological changes in these baked goods. The objective of this study was to systematically evaluate the evolution of color and shape during baking to determine useful correlations that can be implemented during the assessment and modeling of the baking process. Cookies (AACC-I standard protocol 10-53.01) were baked at 185, 205, and 225°C. Moisture content, water activity, surface temperature, characteristic dimensions (radius and thickness), and color indexes (lightness, redness, blueness, and browning index [BI]) were monitored at different locations on the cookie surface and baking times. Relationships among the tested conditions were explored using correlation analysis. The cookies' dimensions and color indexes were strongly correlated with changes in moisture content over time, and those relationships were characterized using empirical models. The temperature dependence of the kinetic parameters of the changes in lightness and BI was also described and deemed independent of the location on the cookie surface. This study provides insights into the influence of heat and mass transfer on the physical and physicochemical changes of cookies during baking. The kinetic and secondary models developed in this study can serve as important components for establishing a comprehensive approach for coupling heat transfer, mass transfer, and reaction kinetics to estimate and optimize cookie-baking processes. PRACTICAL APPLICATION: The findings from this study provide valuable information for better understanding the morphological changes and color developments during the cookie-baking process. The quantitative data and models generated in this study will allow identifying baking conditions for better quality development.