Concerted variation in melanogenesis genes underlies emergent patterning of plumage in capuchino seedeaters

Coloration traits are central to animal communication; they often govern mate choice, promote reproductive isolation and catalyse speciation. Specific genetic changes can cause variation in coloration, yet far less is known about how overall coloration patterns—which involve combinations of multiple colour patches across the body—can arise and are genomically controlled. We performed genome-wide association analyses to link genomic changes to variation in melanin (eumelanin and pheomelanin) concentration in feathers from different body parts in the capuchino seedeaters, an avian radiation with diverse colour patterns despite remarkably low genetic differentiation across species. Cross-species colour variation in each plumage patch is associated with unique combinations of variants at a few genomic regions, which include mostly non-coding (presumably regulatory) areas close to known pigmentation genes. Genotype–phenotype associations can vary depending on patch colour and are stronger for eumelanin pigmentation, suggesting eumelanin production is tightly regulated. Although some genes are involved in colour variation in multiple patches, in some cases, the SNPs associated with colour changes in different patches segregate spatially. These results suggest that coloration patterning in capuchinos is generated by the modular combination of variants that regulate multiple melanogenesis genes, a mechanism that may have promoted this rapid radiation.

Different Colour Predictions of Facial Preference by Caucasian and Chinese Observers

Facial colour characteristics convey vital personal information and influence social interactions and mate choices as contributing factors to perceived beauty, health, and age. How various colour characteristics would affect facial preference and whether there is a cultural difference are not fully understood. Here, we provide a useful and repeatable methodology for skin colour research based on a realistic skin model to investigate the effect of various facial colour characteristics on facial preference and compare the role of colour predictors in Caucasian (CA) and Chinese (CN) populations. Our results show that, although the averaged skin colour of facial areas plays a limited role, together with colour variation and contrast, there are stronger links between colour and facial preference than previously revealed. We also find large cultural differences in facial colour perceptions. Interestingly, Chinese observers tend to rely more heavily on colour cues to judge facial preference than Caucasian observers.

Addition of Trans-Resveratrol-Loaded Highly Concentrated Double Emulsion to Yoghurts: Effect on Physicochemical Properties

Trans-resveratrol (RSV) needs to be encapsulated to maintain its beneficial properties on the human body. This is due to its extreme photosensitivity, short biological half-life, and easy oxidation. In this study, the use of double emulsions for RSV encapsulation and their further application on functional yoghurts was studied. Different types of yoghurts were prepared: with and without RSV and with two types of volumetric emulsion formulations (20/80 and 30/70). In order to study the influence of the addition of double emulsions to the physical properties of the prepared yoghurts, they were characterised fresh and after a month under storage at 4 °C, in terms of droplet size, morphology, stability, rheology, texturometry, colorimetry, and antioxidant capacity. Results obtained showed that the presence of emulsion in the yoghurts produced a generalised decrease in the predominant droplet size (from 48 µm to 15–25 µm) and an increase in the stability. Additionally, a predominantly elastic character was observed. The firmness values obtained were very similar for all the yoghurts analysed and did not suffer important modifications with time. A slight colour variation was observed with storage time in the control sample, whereas a more notable variation in the case of emulsion yoghurts was observed. An appreciable increase of the antioxidant capacity of the final functional yoghurt (100 g) was observed when it contained 5–8 mg of RSV. Encapsulated RSV added to yoghurts presented a larger protection against RSV oxidation compared with free RSV, presenting a larger antioxidant inhibition after one month of storage. Moreover, the antioxidant capacity of yoghurts with encapsulated RSV was not affected under storage, since slight reductions (3%) were registered after one month of storage at 4 °C.

COMPARISON OF TWO MICROWAVE DRYING TECHNIQUES FOR CEREAL SEEDS AND DETERMINATION OF THEIR PHYSICAL PARAMETERS

The microwave drying of wheat and corn seeds by two technologies at different working powers is studied here. The main objective is to evaluate the effect of microwaves on variations in the moisture, colour and size of the seeds after microwave drying. The tests are performed in microwave ovens with and without inverter technology at three drying powers (260, 440 and 620 W). It has been observed that increasing drying power results in a ~50% reduction in drying time and a seed moisture level below 14%. The colour variation of the seeds is insignificant between microwave drying with and without the inverter. However, there is also an unacceptable decrease in size for both types of seeds with increasing drying power, which can lead to increased shrinkage of the seeds and the appearance of cracks, especially in the corn seeds.

Recording Persicaria maculosa and P. lapathifolia (Polygonaceae)

Persicaria maculosa Gray (Redshank) is a distinct species which can be distinguished from all forms of P. lapathifolia (L.) Delarbe (Pale Persicaria) based on the outer tepal veins. The recording and identification of these two taxa can be clouded by colour variation (especially in the latter species) and due to varied treatments in different works or Floras. This article describes ways to separate the two species and gives details of the various treatments in order for others to decide which taxonomic work should be followed. It suggests that there is a greater need for further morphological and or molecular studies for this complex group in order to form a consensus. Hybrids may occur but none have been confirmed by scientific methods. It may be that most of these taxa (especially in P. lapathifolia s.l.) are recognizable as forms or varieties, and this is also suggested (informally at present) by the author below, until further work clarifies the situation.

Phylogeography, colouration, and cryptic speciation across the Indo-Pacific in the sea urchin genus Echinothrix

The sea urchins Echinothrix calamaris and Echinothrix diadema have sympatric distributions throughout the Indo-Pacific. Diverse colour variation is reported in both species. To reconstruct the phylogeny of the genus and assess gene flow across the Indo-Pacific we sequenced mitochondrial 16S rDNA, ATPase-6, and ATPase-8, and nuclear 28S rDNA and the Calpain-7 intron. Our analyses revealed that E. diadema formed a single trans-Indo-Pacific clade, but E. calamaris contained three discrete clades. One clade was endemic to the Red Sea and the Gulf of Oman. A second clade occurred from Malaysia in the West to Moorea in the East. A third clade of E. calamaris was distributed across the entire Indo-Pacific biogeographic region. A fossil calibrated phylogeny revealed that the ancestor of E. diadema diverged from the ancestor of E. calamaris ~ 16.8 million years ago (Ma), and that the ancestor of the trans-Indo-Pacific clade and Red Sea and Gulf of Oman clade split from the western and central Pacific clade ~ 9.8 Ma. Time since divergence and genetic distances suggested species level differentiation among clades of E. calamaris. Colour variation was extensive in E. calamaris, but not clade or locality specific. There was little colour polymorphism in E. diadema.

Colour variation linked to host-plants in the endemic beetle currently known as Ceutorhynchus contractus (Marsham, 1802) form pallipes Crotch, 1866 (Coleoptera: Curculionidae) on Lundy, Devon

Uniquely in Britain, the small island of Lundy has an endemic plant that supports two species of beetles that are also endemic. The Lundy Cabbage Weevil (currently called Ceutorhynchus contractus form pallipes) was originally distinguished from mainland C. contractus by its yellow legs, but genetic and morphological studies have shown that f. pallipes can have either black or yellow legs. Over a period of 25 years we monitored the frequencies of the two colour varieties on its two main food plants, Coincya wrightii and Cochlearia danica. Consistent differences were maintained, with roughly equal colour frequencies on Coincya wrightii and black individuals more common on Cochlearia danica, even when host-plants were growing close together. We provide possible explanations for this persistent but enigmatic difference.

Colour variation of the Maltese wall lizards (Podarcis filfolensis) at population and individual levels in the Linosa island

The research on animal colouration has always been of great interest for biologists but since the last decades it has grown exponentially thanks to multidisciplinary approaches. Animals have found several ways to deal with the camouflage/communication trade-off in colouration, leading to the evolution of alternative patterns of variation of colourations at different levels including signal partitioning and spatial resolution of colouration. In this paper we analyse the variability of dorsal and ventral colouration in males and females of Maltese wall lizards in three populations on Linosa. We collected high-resolution digital images of dorsal, ventral and throat colouration from 61 lizards (32 males and 29 females). We showed that the colouration differs among sexes and body regions within the same individual. Colourations are also variable among individuals within population, as well as among different populations across the Island. Finally, we detected a lizard’s colouration shifts with increasing body size. Those result supports the hypothesis that colouration in this species evolved under the competing pressures of natural and sexual selection to promote signals that are visible to conspecifics while being less perceptible to avian predators. Graphic abstract