Journal articles: 'Animal coloration'

1

Caro, Tim, Mary Caswell Stoddard, and Devi Stuart-Fox. "Animal coloration research: why it matters." Philosophical Transactions of the Royal Society B: Biological Sciences 372, no. 1724 (May 22, 2017): 20160333. http://dx.doi.org/10.1098/rstb.2016.0333.

Full text

Abstract:

While basic research on animal coloration is the theme of this special edition, here we highlight its applied significance for industry, innovation and society. Both the nanophotonic structures producing stunning optical effects and the colour perception mechanisms in animals are extremely diverse, having been honed over millions of years of evolution for many different purposes. Consequently, there is a wealth of opportunity for biomimetic and bioinspired applications of animal coloration research, spanning colour production, perception and function. Fundamental research on the production and perception of animal coloration is contributing to breakthroughs in the design of new materials (cosmetics, textiles, paints, optical coatings, security labels) and new technologies (cameras, sensors, optical devices, robots, biomedical implants). In addition, discoveries about the function of animal colour are influencing sport, fashion, the military and conservation. Understanding and applying knowledge of animal coloration is now a multidisciplinary exercise. Our goal here is to provide a catalyst for new ideas and collaborations between biologists studying animal coloration and researchers in other disciplines. This article is part of the themed issue ‘Animal coloration: production, perception, function and application’.

APA, Harvard, Vancouver, ISO, and other styles

2

Taylor, Lisa A., and Kevin J. McGraw. "Animal Coloration: Sexy Spider Scales." Current Biology 17, no. 15 (August 2007): R592—R593. http://dx.doi.org/10.1016/j.cub.2007.05.064.

Full text

APA, Harvard, Vancouver, ISO, and other styles

3

Galán, Pedro. "Ontogenetic and sexual variation in the coloration of the lacertid lizards Iberolacerta monticola and Podarcis bocagei. Do the females prefer the greener males?" Animal Biology 58, no. 2 (2008): 173–98. http://dx.doi.org/10.1163/157075608x328026.

Full text

Abstract:

AbstractChanges in the coloration of the lacertid lizards Iberolacerta monticola and Podarcis bocagei with age in populations from NW Spain are described. The onset of sexual maturity in P. bocagei males involves a change in the ventral (yellow) and dorsal (green) colorations, which is different from immature males (dorsally brownish in color). In I. monticola males, the ventral coloration also changes to a deep green when they reach maturity, while the dorsal coloration remains brownish as in the immature specimens. In this species, the green dorsal coloration is acquired gradually after maturity. Only the oldest individuals have a predominantly green dorsal coloration. The differences between the two species in the time males take to acquire the green dorsal coloration could be related to their different longevity. The coloring is acquired gradually in the most long-lived species (I. monticola). A field study was carried out on the behaviour of adult males of I. monticola during the reproductive period. The males with green dorsal coloration were seen to pair with females significantly more frequently than those with the brownish dorsal color. The increase in the green dorsal coloration (conspicuous) with the size and age of the males of this species would appear to have a clear function as an intersexual or intrasexual signal.

APA, Harvard, Vancouver, ISO, and other styles

4

San-Jose, Luis M., and Alexandre Roulin. "Genomics of coloration in natural animal populations." Philosophical Transactions of the Royal Society B: Biological Sciences 372, no. 1724 (May 22, 2017): 20160337. http://dx.doi.org/10.1098/rstb.2016.0337.

Full text

Abstract:

Animal coloration has traditionally been the target of genetic and evolutionary studies. However, until very recently, the study of the genetic basis of animal coloration has been mainly restricted to model species, whereas research on non-model species has been either neglected or mainly based on candidate approaches, and thereby limited by the knowledge obtained in model species. Recent high-throughput sequencing technologies allow us to overcome previous limitations, and open new avenues to study the genetic basis of animal coloration in a broader number of species and colour traits, and to address the general relevance of different genetic structures and their implications for the evolution of colour. In this review, we highlight aspects where genome-wide studies could be of major utility to fill in the gaps in our understanding of the biology and evolution of animal coloration. The new genomic approaches have been promptly adopted to study animal coloration although substantial work is still needed to consider a larger range of species and colour traits, such as those exhibiting continuous variation or based on reflective structures. We argue that a robust advancement in the study of animal coloration will also require large efforts to validate the functional role of the genes and variants discovered using genome-wide tools. This article is part of the themed issue ‘Animal coloration: production, perception, function and application’.

APA, Harvard, Vancouver, ISO, and other styles

5

Lakhani, Leena. "PROTECTIVE COLORATION IN ANIMALS." International Journal of Research -GRANTHAALAYAH 2, no. 3SE (December 31, 2014): 1–5. http://dx.doi.org/10.29121/granthaalayah.v2.i3se.2014.3515.

Full text

Abstract:

Animals have range of defensive markings which helps to the risk of predator detection (camouflage), warn predators of the prey’s unpalatability (aposematism) or fool a predator into mimicry, masquerade. Animals also use colors in advertising, signalling services such as cleaning to animals of other species, to signal sexual status to other members of the same species. Some animals use color to divert attacks by startle (dalmatic behaviour), surprising a predator e.g. witheyespots or other flashes of color or possibly by motion dazzle, confusing a predator attack by moving a bold pattern like zebra stripes. Some animals are colored for physical protection, such as having pigments in the skin to protect against sunburn; some animals can lighten or darken their skin for temperature regulation. This adaptive mechanism is known as protective coloration. After several years of evolution, most animals now achieved the color pattern most suited for their natural habitat and role in the food chains. Animals in the world rely on their coloration for either protection from predators, concealment from prey or sexual selection. In general the purpose of protective coloration is to decrease an organism’s visibility or to alter its appearance to other organisms. Sometimes several forms of protective coloration are superimposed on one animal.

APA, Harvard, Vancouver, ISO, and other styles

6

Stevens, Martin, Innes C. Cuthill, Amy M. M. Windsor, and Hannah J. Walker. "Disruptive contrast in animal camouflage." Proceedings of the Royal Society B: Biological Sciences 273, no. 1600 (July 5, 2006): 2433–38. http://dx.doi.org/10.1098/rspb.2006.3614.

Full text

Abstract:

Camouflage typically involves colour patterns that match the background. However, it has been argued that concealment may be achieved by strategic use of apparently conspicuous markings. Recent evidence supports the theory that the presence of contrasting patterns placed peripherally on an animal's body (disruptive coloration) provides survival advantages. However, no study has tested a key prediction from the early literature that disruptive coloration is effective even when some colour patches do not match the background and have a high contrast with both the background and adjacent pattern elements (disruptive contrast). We test this counter-intuitive idea that conspicuous patterns might aid concealment, using artificial moth-like targets with pattern elements designed to match or mismatch the average luminance (lightness) of the trees on which they were placed. Disruptive coloration was less effective when some pattern elements did not match the background luminance. However, even non-background-matching disruptive patterns reduced predation relative to equivalent non-disruptive patterns or to unpatterned controls. Therefore, concealment may still be achieved even when an animal possesses markings not found in the background. Disruptive coloration may allow animals to exploit backgrounds on which they are not perfectly matched, and to possess conspicuous markings while still retaining a degree of camouflage.

APA, Harvard, Vancouver, ISO, and other styles

7

Bar-Oz, G., and S. Lev-Yadun. "Paleolithic cave rock art, animal coloration, and specific animal habitats." Proceedings of the National Academy of Sciences 109, no. 20 (April 16, 2012): E1212. http://dx.doi.org/10.1073/pnas.1200729109.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

Stevens, Martin. "Concealing Coloration in Animals." Animal Behaviour 86, no. 6 (December 2013): 1333–34. http://dx.doi.org/10.1016/j.anbehav.2013.09.024.

Full text

APA, Harvard, Vancouver, ISO, and other styles

9

Caro, Tim, Mary Caswell Stoddard, and Devi Stuart-Fox. "Animal coloration: production, perception, function and application." Philosophical Transactions of the Royal Society B: Biological Sciences 372, no. 1724 (May 22, 2017): 20170047. http://dx.doi.org/10.1098/rstb.2017.0047.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

STEVENS, MARTIN, C. ALEJANDRO PÁRRAGA, INNES C. CUTHILL, JULIAN C. PARTRIDGE, and TOM S. TROSCIANKO. "Using digital photography to study animal coloration." Biological Journal of the Linnean Society 90, no. 2 (January 31, 2007): 211–37. http://dx.doi.org/10.1111/j.1095-8312.2007.00725.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

11

Cardoso, Gonçalo C., and Ana Cristina R. Gomes. "Using Reflectance Ratios to Study Animal Coloration." Evolutionary Biology 42, no. 3 (May 29, 2015): 387–94. http://dx.doi.org/10.1007/s11692-015-9328-5.

Full text

APA, Harvard, Vancouver, ISO, and other styles

12

Potash, Alex D., Daniel U. Greene, Gabrielle A. Foursa, Verity L. Mathis, L. Mike Conner, and Robert A. McCleery. "A comparison of animal color measurements using a commercially available digital color sensor and photograph analysis." Current Zoology 66, no. 6 (March 27, 2020): 601–6. http://dx.doi.org/10.1093/cz/zoaa016.

Full text

Abstract:

Abstract An animal’s pelage, feather, or skin color can serve a variety of functions, so it is important to have multiple standardized methods for measuring color. One of the most common and reliable methods for measuring animal coloration is the use of standardized digital photographs of animals. New technology in the form of a commercially available handheld digital color sensor could provide an alternative to photography-based animal color measurements. To determine whether a digital color sensor could be used to measure animal coloration, we tested the ability of a digital color sensor to measure coloration of mammalian, avian, and lepidopteran museums specimens. We compared results from the sensor to measurements taken using traditional photography methods. Our study yielded significant differences between photography-based and digital color sensor measurements of brightness (light to dark) and colors along the green to red spectrum. There was no difference between photographs and the digital color sensor measurements for colors along the blue to yellow spectrum. The average difference in recorded color (ΔE) by the 2 methods was above the threshold at which humans can perceive a difference. There were significant correlations between the sensor and photographs for all measurements indicating that the sensor is an effective animal coloration measuring tool. However, the sensor’s small aperture and narrow light spectrum range designed for human-vision limit its value for ecological research. We discuss the conditions in which a digital color sensor can be an effective tool for measuring animal coloration in both laboratory settings and in the field.

APA, Harvard, Vancouver, ISO, and other styles

13

Alvarado, Sebastian G. "Molecular Plasticity in Animal Pigmentation: Emerging Processes Underlying Color Changes." Integrative and Comparative Biology 60, no. 6 (October 26, 2020): 1531–43. http://dx.doi.org/10.1093/icb/icaa142.

Full text

Abstract:

Synopsis Animal coloration has been rigorously studied and has provided morphological implications for fitness with influences over social behavior, predator–prey interactions, and sexual selection. In vertebrates, its study has developed our understanding across diverse fields ranging from behavior to molecular biology. In the search for underlying molecular mechanisms, many have taken advantage of pedigree-based and genome-wide association screens to reveal the genetic architecture responsible for pattern variation that occurs in early development. However, genetic differences do not provide a full picture of the dynamic changes in coloration that are most prevalent across vertebrates at the molecular level. Changes in coloration that occur in adulthood via phenotypic plasticity rely on various social, visual, and dietary cues independent of genetic variation. Here, I will review the contributions of pigment cell biology to animal color changes and recent studies describing their molecular underpinnings and function. In this regard, conserved epigenetic processes such as DNA methylation play a role in lending plasticity to gene regulation as it relates to chromatophore function. Lastly, I will present African cichlids as emerging models for the study of pigmentation and molecular plasticity for animal color changes. I posit that these processes, in a dialog with environmental stimuli, are important regulators of variation and the selective advantages that accompany a change in coloration for vertebrate animals.

APA, Harvard, Vancouver, ISO, and other styles

14

Stuart-Fox, Devi, Elizabeth Newton, and Susana Clusella-Trullas. "Thermal consequences of colour and near-infrared reflectance." Philosophical Transactions of the Royal Society B: Biological Sciences 372, no. 1724 (May 22, 2017): 20160345. http://dx.doi.org/10.1098/rstb.2016.0345.

Full text

Abstract:

The importance of colour for temperature regulation in animals remains controversial. Colour can affect an animal's temperature because all else being equal, dark surfaces absorb more solar energy than do light surfaces, and that energy is converted into heat. However, in reality, the relationship between colour and thermoregulation is complex and varied because it depends on environmental conditions and the physical properties, behaviour and physiology of the animal. Furthermore, the thermal effects of colour depend as much on absorptance of near-infrared ((NIR), 700–2500 nm) as visible (300–700 nm) wavelengths of direct sunlight; yet the NIR is very rarely considered or measured. The few available data on NIR reflectance in animals indicate that the visible reflectance is often a poor predictor of NIR reflectance. Adaptive variation in animal coloration (visible reflectance) reflects a compromise between multiple competing functions such as camouflage, signalling and thermoregulation. By contrast, adaptive variation in NIR reflectance should primarily reflect thermoregulatory requirements because animal visual systems are generally insensitive to NIR wavelengths. Here, we assess evidence and identify key research questions regarding the thermoregulatory function of animal coloration, and specifically consider evidence for adaptive variation in NIR reflectance. This article is part of the themed issue ‘Animal coloration: production, perception, function and application’.

APA, Harvard, Vancouver, ISO, and other styles

15

Pike, Thomas W. "Interference coloration as an anti-predator defence." Biology Letters 11, no. 4 (April 2015): 20150159. http://dx.doi.org/10.1098/rsbl.2015.0159.

Full text

Abstract:

Interference coloration, in which the perceived colour varies predictably with the angle of illumination or observation, is extremely widespread across animal groups. However, despite considerable advances in our understanding of the mechanistic basis of interference coloration in animals, we still have a poor understanding of its function. Here, I show, using avian predators hunting dynamic virtual prey, that the presence of interference coloration can significantly reduce a predator's attack success. Predators required more pecks to successfully catch interference-coloured prey compared with otherwise identical prey items that lacked interference coloration, and attacks against prey with interference colours were less accurate, suggesting that changes in colour or brightness caused by prey movement hindered a predator's ability to pinpoint their exact location. The pronounced anti-predator benefits of interference coloration may explain why it has evolved independently so many times.

APA, Harvard, Vancouver, ISO, and other styles

16

Fontaine, Joseph J., and Karie L. Decker. "Exploring Predation and Animal Coloration through Outdoor Activity." Science Activities: Classroom Projects and Curriculum Ideas 45, no. 4 (January 2009): 3–8. http://dx.doi.org/10.3200/sats.45.4.3-8.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Cloudsley-Thompson, J. L. "Multiple Factors in the Evolution of Animal Coloration." Naturwissenschaften 86, no. 3 (March 3, 1999): 123–32. http://dx.doi.org/10.1007/s001140050584.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Wybouw, Nicky, Andre H. Kurlovs, Robert Greenhalgh, Astrid Bryon, Olivia Kosterlitz, Yuki Manabe, Masahiro Osakabe, John Vontas, Richard M. Clark, and Thomas Van Leeuwen. "Convergent evolution of cytochrome P450s underlies independent origins of keto-carotenoid pigmentation in animals." Proceedings of the Royal Society B: Biological Sciences 286, no. 1907 (July 17, 2019): 20191039. http://dx.doi.org/10.1098/rspb.2019.1039.

Full text

Abstract:

Keto-carotenoids contribute to many important traits in animals, including vision and coloration. In a great number of animal species, keto-carotenoids are endogenously produced from carotenoids by carotenoid ketolases. Despite the ubiquity and functional importance of keto-carotenoids in animals, the underlying genetic architectures of their production have remained enigmatic. The body and eye colorations of spider mites (Arthropoda: Chelicerata) are determined by β-carotene and keto-carotenoid derivatives. Here, we focus on a carotenoid pigment mutant of the spider mite Tetranychus kanzawai that , as shown by chromatography, lost the ability to produce keto-carotenoids. We employed bulked segregant analysis and linked the causal locus to a single narrow genomic interval. The causal mutation was fine-mapped to a minimal candidate region that held only one complete gene, the cytochrome P450 monooxygenase CYP384A1 , of the CYP3 clan. Using a number of genomic approaches, we revealed that an inactivating deletion in the fourth exon of CYP384A1 caused the aberrant pigmentation. Phylogenetic analysis indicated that CYP384A1 is orthologous across mite species of the ancient Trombidiformes order where carotenoids typify eye and body coloration, suggesting a deeply conserved function of CYP384A1 as a carotenoid ketolase. Previously, CYP2J19, a cytochrome P450 of the CYP2 clan, has been identified as a carotenoid ketolase in birds and turtles. Our study shows that selection for endogenous production of keto-carotenoids led to convergent evolution, whereby cytochrome P450s were independently co-opted in vertebrate and invertebrate animal lineages.

APA, Harvard, Vancouver, ISO, and other styles

19

Shawkey, Matthew D., and Liliana D'Alba. "Interactions between colour-producing mechanisms and their effects on the integumentary colour palette." Philosophical Transactions of the Royal Society B: Biological Sciences 372, no. 1724 (May 22, 2017): 20160536. http://dx.doi.org/10.1098/rstb.2016.0536.

Full text

Abstract:

Animal integumentary coloration plays a crucial role in visual communication and camouflage, and varies extensively among and within species and populations. To understand the pressures underlying such diversity, it is essential to elucidate the mechanisms by which animals have created novel integumentary coloration. Colours can be produced by selective absorption of light by skin pigments, through light scattering by structured or unstructured tissues, or by a combination of pigments and nanostructures. In this review, we highlight our current understanding of the interactions between pigments and structural integumentary tissues and molecules. We analyse the available evidence suggesting that these combined mechanisms are capable of creating colours and optical properties unachievable by either mechanism alone, thereby effectively expanding the animal colour palette. Moreover, structural and pigmentary colour mechanisms frequently interact in unexpected and overlooked ways, suggesting that classification of colours as being of any particular type may be difficult. Finally, we discuss how these mixtures are useful for investigating the largely unknown genetic, developmental and physical processes generating phenotypic diversity. This article is part of the themed issue ‘Animal coloration: production, perception, function and application’.

APA, Harvard, Vancouver, ISO, and other styles

20

Brush, Alan H. "Bird Coloration." Auk 124, no. 3 (2007): 1097. http://dx.doi.org/10.1642/0004-8038(2007)124[1097:bc]2.0.co;2.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Brush, Alan H. "Bird Coloration." Auk 124, no. 3 (July 1, 2007): 1097–99. http://dx.doi.org/10.1093/auk/124.3.1097.

Full text

Abstract:

Abstract The following critiques express the opinions of the individual evaluators regarding the strengths, weaknesses, and value of the books they review. As such, the appraisals are subjective assessments and do not necessarily reflect the opinions of the editors or any official policy of the American Ornithologists' Union.

APA, Harvard, Vancouver, ISO, and other styles

22

Stevens, Martin, Isabel S. Winney, Abi Cantor, and Julia Graham. "Outline and surface disruption in animal camouflage." Proceedings of the Royal Society B: Biological Sciences 276, no. 1657 (November 18, 2008): 781–86. http://dx.doi.org/10.1098/rspb.2008.1450.

Full text

Abstract:

Camouflage is an important strategy in animals to prevent predation. This includes disruptive coloration, where high-contrast markings placed at an animal's edge break up the true body shape. Successful disruption may also involve non-marginal markings found away from the body outline that create ‘false edges’ more salient than the true body form (‘surface disruption’). However, previous work has focused on breaking up the true body outline, not on surface disruption. Furthermore, while high contrast may enhance disruption, it is untested where on the body different contrasts should be placed for maximum effect. We used artificial prey presented to wild avian predators in the field, to determine the effectiveness of surface disruption, and of different luminance contrast placed in different prey locations. Disruptive coloration was no more effective when comprising high luminance contrast per se , but its effectiveness was dramatically increased with high-contrast markings placed away from the body outline, creating effective surface disruption. A model of avian visual edge processing showed that surface disruption does not make object detection more difficult simply by creating false edges away from the true body outline, but its effect may also be based on a different visual mechanism. Our study has implications for whether animals can combine disruptive coloration with other ‘conspicuous’ signalling strategies.

APA, Harvard, Vancouver, ISO, and other styles

23

Endler, John A., and Johanna Mappes. "The current and future state of animal coloration research." Philosophical Transactions of the Royal Society B: Biological Sciences 372, no. 1724 (May 22, 2017): 20160352. http://dx.doi.org/10.1098/rstb.2016.0352.

Full text

Abstract:

Animal colour patterns are a model system for understanding evolution because they are unusually accessible for study and experimental manipulation. This is possible because their functions are readily identifiable. In this final paper of the symposium we provide a diagram of the processes affecting colour patterns and use this to summarize their functions and put the other papers in a broad context. This allows us to identify significant ‘holes’ in the field that only become obvious when we see the processes affecting colour patterns, and their interactions, as a whole. We make suggestions about new directions of research that will enhance our understanding of both the evolution of colour patterns and visual signalling but also illuminate how the evolution of multiple interacting traits works. This article is part of the themed issue ‘Animal coloration: production, perception, function and application’.

APA, Harvard, Vancouver, ISO, and other styles

24

Stoddard, Mary Caswell, and Daniel Osorio. "Animal Coloration Patterns: Linking Spatial Vision to Quantitative Analysis." American Naturalist 193, no. 2 (February 2019): 164–86. http://dx.doi.org/10.1086/701300.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Cardoso, Gonçalo C., and Ana Cristina R. Gomes. "Erratum to: Using Reflectance Ratios to Study Animal Coloration." Evolutionary Biology 42, no. 4 (September 22, 2015): 511–12. http://dx.doi.org/10.1007/s11692-015-9344-5.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Cuthill, Innes C., and Aron Székely. "Coincident disruptive coloration." Philosophical Transactions of the Royal Society B: Biological Sciences 364, no. 1516 (November 6, 2008): 489–96. http://dx.doi.org/10.1098/rstb.2008.0266.

Full text

Abstract:

Even if an animal matches its surroundings perfectly in colour and texture, any mismatch between the spatial phase of its pattern and that of the background, or shadow created by its three-dimensional relief, is potentially revealing. Nevertheless, for camouflage to be fully broken, the shape must be recognizable. Disruptive coloration acts against object recognition by the use of high-contrast internal colour boundaries to break up shape and form. As well as the general outline, characteristic features such as eyes and limbs must also be concealed; this can be achieved by having the colour patterns on different, but adjacent, body parts aligned to match each other (i.e. in phase). Such ‘coincident disruptive coloration’ ensures that there is no phase disjunction where body parts meet, and causes different sections of the body to blend perceptually. We tested this theory using field experiments with predation by wild birds on artificial moth-like targets, whose wings and (edible pastry) bodies had colour patterns that were variously coincident or not. We also carried out an experiment with humans searching for analogous targets on a computer screen. Both experiments show that coincident disruptive coloration is an effective mechanism for concealing an otherwise revealing body form.

APA, Harvard, Vancouver, ISO, and other styles

27

Feller, Kathryn D., Thomas M. Jordan, David Wilby, and Nicholas W. Roberts. "Selection of the intrinsic polarization properties of animal optical materials creates enhanced structural reflectivity and camouflage." Philosophical Transactions of the Royal Society B: Biological Sciences 372, no. 1724 (May 22, 2017): 20160336. http://dx.doi.org/10.1098/rstb.2016.0336.

Full text

Abstract:

Many animals use structural coloration to create bright and conspicuous visual signals. Selection of the size and shape of the optical structures animals use defines both the colour and intensity of the light reflected. The material used to create these reflectors is also important; however, animals are restricted to a limited number of materials: commonly chitin, guanine and the protein, reflectin. In this work we highlight that a particular set of material properties can also be under selection in order to increase the optical functionality of structural reflectors. Specifically, polarization properties, such as birefringence (the difference between the refractive indices of a material) and chirality (which relates to molecular asymmetry) are both under selection to create enhanced structural reflectivity. We demonstrate that the structural coloration of the gold beetle Chrysina resplendens and silvery reflective sides of the Atlantic herring, Clupea harengus are two examples of this phenomenon. Importantly, these polarization properties are not selected to control the polarization of the reflected light as a source of visual information per se. Instead, by creating higher levels of reflectivity than are otherwise possible, such internal polarization properties improve intensity-matching camouflage. This article is part of the themed issue ‘Animal coloration: production, perception, function and application’.

APA, Harvard, Vancouver, ISO, and other styles

28

Seddon, Ryan, and Matthew Klukowski. "Secondary sexual coloration is related to white blood cell counts and testosterone in male southeastern five-lined skinks (Plestiodon inexpectatus)." Amphibia-Reptilia 34, no. 4 (2013): 585–89. http://dx.doi.org/10.1163/15685381-00002914.

Full text

Abstract:

The immunocompetence handicap hypothesis posits that secondary sexual coloration can honestly signal male quality because elevated testosterone, which is necessary for the expression of the coloration, also handicaps males through immunosuppression. Thus only high quality males can express the showiest coloration in spite of immunosuppression. Here we report a test of the immunocompetence handicap hypothesis in southeastern five-lined skinks, Plestiodon inexpectatus, which exhibit a reddish-orange head coloration during the breeding season. We tested whether head coloration is related to circulating testosterone concentrations and reflects the status of a male’s immune system, as measured by total leukocyte counts. As predicted, hue, saturation, and extent of head coloration were correlated with plasma testosterone, and the brightness of the head was negatively correlated with total circulating leukocytes. While results are consistent with the immunocompetence handicap hypothesis, additional studies that include experimental manipulations of testosterone levels and measure other aspects of immunity are warranted.

APA, Harvard, Vancouver, ISO, and other styles

29

van der Sluijs, Inke, Ole Seehausen, Tom J. M. Van Dooren, and Jacques J. M. van Alphen. "No evidence for a genetic association between female mating preference and male secondary sexual trait in a Lake Victoria cichlid fish." Current Zoology 56, no. 1 (February 1, 2010): 57–64. http://dx.doi.org/10.1093/czoolo/56.1.57.

Full text

Abstract:

Abstract Sexual selection by female mating preference for male nuptial coloration has been suggested as a driving force in the rapid speciation of Lake Victoria cichlid fish. This process could have been facilitated or accelerated by genetic associations between female preference loci and male coloration loci. Preferences, as well as coloration, are heritable traits and are probably determined by more than one gene. However, little is known about potential genetic associations between these traits. In turbid water, we found a population that is variable in male nuptial coloration from blue to yellow to red. Males at the extreme ends of the phenotype distribution resemble a reproductively isolated species pair in clear water that has diverged into one species with blue-grey males and one species with bright red males. Females of the turbid water population vary in mating preference coinciding with the male phenotype distribution. For the current study, these females were mated to blue males. We measured the coloration of the sires and male offspring. Parents-offspring regression showed that the sires did not affect male offspring coloration, which confirms earlier findings that the blue species breeds true. In contrast, male offspring coloration was determined by the identity of the dams, which suggests that there is heritable variation in male color genes between females. However, we found that mating preferences of the dams were not correlated with male offspring coloration. Thus, there is no evidence for strong genetic linkage between mating preference and the preferred trait in this population.

APA, Harvard, Vancouver, ISO, and other styles

30

de Sá, Rafael O., and Esteban O. Lavilla. "The tadpole of Pseudis minuta (Anura: Pseudidae), an apparent case of heterochrony." Amphibia-Reptilia 18, no. 3 (1997): 229–40. http://dx.doi.org/10.1163/156853897x00116.

Full text

Abstract:

AbstractThe external morphology, oral disc, and coloration pattern of the larva of Pseudis minuta are described. Tadpoles are mostly bottom dwellers that have a small, terminal oral disc with a labial tooth row formula 1(1-1)/(1-1)2. Internal oral anatomy is characterized using scanning electron microscopy, representing the only description available for the family Pseudidae. The coloration pattern of P. minuta tadpoles is compared with that of other pseudids. Pseudis minuta larvae do not exhibit the ontogenetic coloration change reported for P. paradoxa. Considering larval coloration, larval size, and reports of adult size, acceleration or hypermorphosis are suggested as possible heterochronic mechanisms involved in the evolution of Pseudis.

APA, Harvard, Vancouver, ISO, and other styles

31

Surmacki, Adrian. "Natural soiling has a small effect on structurally-based plumage coloration." Animal Biology 61, no. 4 (2011): 441–55. http://dx.doi.org/10.1163/157075511x596918.

Full text

Abstract:

AbstractPlumage coloration is an important trait used by birds in mate choice decisions and is often an indicator of social status. The two main types of color-producing mechanisms in feathers are pigment deposition (pigmentary coloration) or the coherent scattering of light reflected from keratin microstructure (structural coloration). External factors acting on the feather surface are also hypothesized to affect structural coloration. Because preening is an energy and time demanding behavior, color variation caused by soiling deposition is generally assumed to strengthen the condition signaling function of plumage coloration. To date, studies using artificial soiling have confirmed those hypotheses. However, information about how natural soiling affects plumage color are still scarce. In this paper, I investigated the effect of natural soiling on structurally-based feather color of blue tits Cyanistes caeruleus. As a method, I applied mechanical cleaning that functionally mimicked natural preening. Removal of soiling caused a decrease of ultraviolet (UV) chroma in males and decrease in brightness in females. According to visual contrast modeling, only changes in brightness should be perceived by birds. Further, more efficient chemical cleaning resulted in a significant increase in brightness in both sexes, presumably due to preen wax removal. These results suggest that the impact of natural feather soiling is not likely to modify structural coloration signaling. One possible explanation is that, under natural conditions, the amount of soil accumulating on feathers is too small to affect coloration.

APA, Harvard, Vancouver, ISO, and other styles

32

McGuire, Jimmy A., and William E. Cooper. "Progesterone induces bright orange throat coloration in female Petrosaurus mearnsi." Amphibia-Reptilia 14, no. 3 (1993): 213–21. http://dx.doi.org/10.1163/156853893x00417.

Full text

Abstract:

AbstractFemale Petrosaurus mearnsi develop orange throat coloration when gravid. This coloration was induced in the nonbreeding season (late fall) by exogenous progesterone delivered by subcutaneous implantation in Silastic capsules or intramuscular injection. Color change was first apparent after five days of administration. The time course of brightening was similar for the two methods. Color change was first apparent after five days, and was detectable in most females receiving implants after six days. For both routes of administration, maximum brightening usually occurred within three days of the time that brightening was first detected. Following removal of implants or termination of daily injections, the throat coloration of most females had begun to fade within 25 to 30 days. However, two injected females did not fade at all after sixty days and none faded completely to pretreatment coloration. This suggests that endogenous steroid production by early winter is insufficient to induce brightening, but it might maintain some degree of artificially induced brightening. Because progesterone has also been shown to induce orange female coloration in a distantly related phrynosomatid species and two species of crotaphytids, we hypothesize that induction of bright female secondary sexual coloration by progesterone may be a widespread trait in iguanian lizards.

APA, Harvard, Vancouver, ISO, and other styles

33

Pérez i de Lanuza, Guillem, and Enrique Font. "Iridescent (angle-dependent reflectance) properties of dorsal coloration in Podarcis muralis (Laurenti, 1768)." Amphibia-Reptilia 37, no. 4 (2016): 441–45. http://dx.doi.org/10.1163/15685381-00003063.

Full text

Abstract:

Iridescence is a visual property of those surfaces that change in colour with viewing angle. Iridescence has been rarely reported in reptiles, but some snakes and lizards show this type of coloration. Here we study the effect of different angles of light incidence and observation on the spectrophotometrically assessed reflectance of dorsal coloration in the lizard Podarcis muralis. The results demonstrate clear angle dependence of several colour parameters. In particular, different angles of light incidence and observation result in changes in hue of more than 30 nm. This suggests that lizard dorsal coloration may be perceived, depending on viewing geometry, as being of different colours by a wide range of potential observers. Functional implications of iridescence in dorsal coloration are discussed.

APA, Harvard, Vancouver, ISO, and other styles

34

Cuxim-Koyoc, Alan, Israel Escalante-Avilés, Rosendo Aragón-Pech, Doris Pinto-Escalante, Enrique Reyes-Novelo, and Hugo A. Ruiz-Piña. "Albinism in Didelphis virginiana (Kerr, 1792): the first reported case in Mexico." Mammalia 84, no. 2 (March 26, 2020): 144–49. http://dx.doi.org/10.1515/mammalia-2018-0164.

Full text

Abstract:

AbstractAtypical colorations occur in different groups of vertebrates. The loss of melanin in the skin, hair and eyes is the result of an autosomal recessive genetic entity. It causes individuals to present with a white coloration of the skin and hair, as well as red eyes, known as albino. This manuscript documents the first record in Mexico of complete albinism in a marsupial, Didelphis virginiana, captured in the Yucatan peninsula.

APA, Harvard, Vancouver, ISO, and other styles

35

ASQUITH, R. S., and A. K. PURI. "Disulphide Exchange as a Method of Coloration of Animal Fibres." Journal of the Society of Dyers and Colourists 87, no. 4 (October 22, 2008): 116–20. http://dx.doi.org/10.1111/j.1478-4408.1971.tb03011.x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

36

Lind, Olle, Miriam J. Henze, Almut Kelber, and Daniel Osorio. "Coevolution of coloration and colour vision?" Philosophical Transactions of the Royal Society B: Biological Sciences 372, no. 1724 (May 22, 2017): 20160338. http://dx.doi.org/10.1098/rstb.2016.0338.

Full text

Abstract:

The evolutionary relationship between signals and animal senses has broad significance, with potential consequences for speciation, and for the efficacy and honesty of biological communication. Here we outline current understanding of the diversity of colour vision in two contrasting groups: the phylogenetically conservative birds, and the more variable butterflies. Evidence for coevolution of colour signals and vision exists in both groups, but is limited to observations of phenotypic differences between visual systems, which might be correlated with coloration. Here, to illustrate how one might interpret the evolutionary significance of such differences, we used colour vision modelling based on an avian eye to evaluate the effects of variation in three key characters: photoreceptor spectral sensitivity, oil droplet pigmentation and the proportions of different photoreceptor types. The models predict that physiologically realistic changes in any one character will have little effect, but complementary shifts in all three can substantially affect discriminability of three types of natural spectra. These observations about the adaptive landscape of colour vision may help to explain the general conservatism of photoreceptor spectral sensitivities in birds. This approach can be extended to other types of eye and spectra to inform future work on coevolution of coloration and colour vision. This article is part of the themed issue ‘Animal coloration: production, perception, function and application’.

APA, Harvard, Vancouver, ISO, and other styles

37

Liu, Hong-Yi, Ke He, Yun-Fa Ge, Qiu-Hong Wan, and Sheng-Guo Fang. "Cape Feather Coloration Signals Different Genotypes of the Most Polymorphic MHC Locus in Male Golden Pheasants (Chrysolophus pictus)." Animals 11, no. 2 (January 22, 2021): 276. http://dx.doi.org/10.3390/ani11020276.

Full text

Abstract:

Ornamental feather coloration is usually a reflection of male quality and plays an important role during courtship, whereas the essence of male quality at the genetic level is not well understood. Major histocompatibility complex (MHC)-based mate choice has been observed in various vertebrates. Here, we investigated the relationship between the coloration of cape feathers and the MHC genotypes in golden pheasants (Chrysolophus pictus). We found that feather coloration differed sharply among different individuals (brightness: 1827.20 ± 759.43, chroma: 1241.90 ± 468.21, hue: 0.46 ± 0.06). Heterozygous individuals at the most polymorphic MHC locus (IA2) had brighter feathers than homozygous individuals (Z = −2.853, p = 0.004) and were more saturated in color (Z = −2.853, p = 0.004). However, feather coloration was not related to other MHC loci or to overall genetic heterozygosity (p > 0.050). Our study suggested that coloration of cape feathers might signal IA2 genotypes in golden pheasants.

APA, Harvard, Vancouver, ISO, and other styles

38

Glover, Jenell A., and Matthew S. Lattanzio. "Female preferences for discrete and continuous male colour expression may help reinforce colour polymorphism in a desert lizard." Behaviour 158, no. 3-4 (February 5, 2021): 315–39. http://dx.doi.org/10.1163/1568539x-bja10068.

Full text

Abstract:

Abstract Despite recognition that colour can vary continuously, colour expression in colour polymorphic species is usually treated as discrete. We conducted three experiments to evaluate the extent that discrete and continuous male coloration influenced female mating preferences in long-tailed brush lizards (Urosaurus graciosus). Each experiment provided females with a different social context: a dimorphic choice between a yellow and an orange male (coloration treated as discrete), and a choice between either two orange males or two yellow males (coloration treated as continuous variation). Females preferred orange males over yellow males in the first experiment, and the findings of our second experiment suggested that males with moderate orange coloration were most preferred. In contrast, females behaved randomly with respect to two yellow males. Our findings show that females in colour polymorphic species can evaluate both discrete and continuous aspects of morph coloration during mate assessment, which may help maintain their polymorphism.

APA, Harvard, Vancouver, ISO, and other styles

39

Caro, Tim, Kasey Brockelsby, Annie Ferrari, Manisha Koneru, Konatsu Ono, Edward Touche, and Theodore Stankowich. "The evolution of primate coloration revisited." Behavioral Ecology 32, no. 4 (July 1, 2021): 555–67. http://dx.doi.org/10.1093/beheco/arab029.

Full text

Abstract:

Abstract Primates are noted for their varied and complex pelage and bare skin coloration but the significance of this diverse coloration remains opaque. Using new updated information, novel scoring of coat and skin coloration, and controlling for shared ancestry, we reexamined and extended findings from previous studies across the whole order and the five major clades within it. Across primates, we found (i) direct and indirect evidence for pelage coloration being driven by protective coloration strategies including background matching, countershading, disruptive coloration, and aposematism, (ii) diurnal primates being more colorful, and (iii) the possibility that pelage color diversity is negatively associated with female trichromatic vision; while (iv) reaffirming avoidance of hybridization driving head coloration in males, (v) darker species living in warm, humid conditions (Gloger’s rule), and (vi) advertising to multiple mating partners favoring red genitalia in females. Nonetheless, the importance of these drivers varies greatly across clades. In strepsirrhines and cercopithecoids, countershading is important; greater color diversity may be important for conspecific signaling in more diurnal and social strepsirrhines; lack of female color vision may be associated with colorful strepsirrhines and platyrrhines; whereas cercopithecoids obey Gloger’s rule. Haplorrhines show background matching, aposematism, character displacement, and red female genitalia where several mating partners are available. Our findings emphasize several evolutionary drivers of coloration in this extraordinarily colorful order. Throughout, we used coarse but rigorous measures of coloration, and our ability to replicate findings from earlier studies opens up opportunities for classifying coloration of large numbers of species at a macroevolutionary scale.

APA, Harvard, Vancouver, ISO, and other styles

40

Wardill, T. J., P. T. Gonzalez-Bellido, R. J. Crook, and R. T. Hanlon. "Neural control of tuneable skin iridescence in squid." Proceedings of the Royal Society B: Biological Sciences 279, no. 1745 (August 15, 2012): 4243–52. http://dx.doi.org/10.1098/rspb.2012.1374.

Full text

Abstract:

Fast dynamic control of skin coloration is rare in the animal kingdom, whether it be pigmentary or structural. Iridescent structural coloration results when nanoscale structures disrupt incident light and selectively reflect specific colours. Unlike animals with fixed iridescent coloration (e.g. butterflies), squid iridophores (i.e. aggregations of iridescent cells in the skin) produce dynamically tuneable structural coloration , as exogenous application of acetylcholine (ACh) changes the colour and brightness output. Previous efforts to stimulate iridophores neurally or to identify the source of endogenous ACh were unsuccessful, leaving researchers to question the activation mechanism. We developed a novel neurophysiological preparation in the squid Doryteuthis pealeii and demonstrated that electrical stimulation of neurons in the skin shifts the spectral peak of the reflected light to shorter wavelengths (greater than 145 nm) and increases the peak reflectance (greater than 245%) of innervated iridophores. We show ACh is released within the iridophore layer and that extensive nerve branching is seen within the iridophore. The dynamic colour shift is significantly faster (17 s) than the peak reflectance increase (32 s), revealing two distinct mechanisms. Responses from a structurally altered preparation indicate that the reflectin protein condensation mechanism explains peak reflectance change, while an undiscovered mechanism causes the fast colour shift.

APA, Harvard, Vancouver, ISO, and other styles

41

Cezário, Rodrigo Roucourt, Vinicius Marques Lopez, Stanislav Gorb, and Rhainer Guillermo-Ferreira. "Dynamic iridescent signals of male copperwing damselflies coupled with wing-clapping displays: the perspective of different receivers." Biological Journal of the Linnean Society 134, no. 1 (June 2, 2021): 229–39. http://dx.doi.org/10.1093/biolinnean/blab068.

Full text

Abstract:

Abstract Dynamic signals are a widespread phenomenon in several taxa, usually associated with intraspecific communication. In contrast, dynamic iridescent signals are detectable only at specific angles of illumination; hence, the animal can hide the signal to avoid detection when necessary. This structural coloration is mostly dependent on the illumination, the contrast against the background and the vision of the receiver. Complex behavioural displays can be coupled with structural coloration to create dynamic visual signals that enhance these functions. Here, we address whether iridescence of the males of a damselfly that inhabits dark rainforests, Chalcopteryx scintillans, can be considered a dynamic visual signal. We analyse whether coloration is perceived by conspecifics, while reducing detectability to eavesdroppers against three types of backgrounds. Our results suggest that the visual background affects the detectability of male hindwings by different receivers, mostly predators and prey. We discuss whether these results and the angle dependence of colour could indicate a mechanism to avoid unwanted intraspecific interactions or even to lure both predators and prey. We conclude that the main functions of the dynamic iridescent signal are to communicate with conspecifics while hindering the signal for prey, adding evidence of the multifunctionality of structural coloration coupled with behavioural displays in animals.

APA, Harvard, Vancouver, ISO, and other styles

42

Reed, Steven, Richard K. Simpson, and Kevin J. McGraw. "Feather morphological predictors of angle-dependent color changes in parrot plumage." Avian Biology Research 13, no. 4 (October 28, 2020): 108–17. http://dx.doi.org/10.1177/1758155920963198.

Full text

Abstract:

Among the most ornate animal traits in nature are the angle-dependent (e.g. iridescent) structural colors of many fishes, damselflies, birds, beetles, and butterflies. Though we now have a solid understanding of the mechanisms that create angle-dependent coloration in several groups, we know little about whether pigmentary colors reflect light in an angle-dependent fashion or if similar or different mechanisms govern angle-dependent reflectance from pigmentary versus structural colors. Here for the first time we describe non-iridescent angle-dependent coloration from the tail and wing feathers of several parrot species (Aves: Psittaciformes). We employed a novel approach—by calculating chromatic and achromatic contrasts (in just noticeable differences, JNDs) of straight and angled measurements of the same feather patch—to test for perceptually relevant angle-dependent changes in coloration on dorsal and ventral feather surfaces. We found, among the 15 parrot species studied, significant angle dependence for seven of our eight feather JND parameters. We then measured micro-scale features on each side of feathers, including size and color of barbs and barbules, to attempt to predict interspecific variation in degree of angle-dependent reflectance. We found that barb height, plumage-color type (e.g. melanin, structural), and differences between barb-barbule coloration (measured using Euclidean distances) were the strongest predictors of angle-dependent coloration. Interestingly, there was no significant phylogenetic signal in any of the angle-dependence models tested. These findings deepen our views on the importance of microscopic feather features in the production of directional animal coloration, especially in tissues that are colored predominantly by pigments and appear to be statically colored.

APA, Harvard, Vancouver, ISO, and other styles

43

Mehlis, Marion, Lukas K. Hilke, and Theo C. M. Bakker. "Attractive males have faster sperm in three-spined sticklebacks Gasterosteus aculeatus." Current Zoology 59, no. 6 (December 1, 2013): 761–68. http://dx.doi.org/10.1093/czoolo/59.6.761.

Full text

Abstract:

Abstract Recent studies have revealed that sexually selected traits may signal sperm quality and hence male fertilisation ability. There is also evidence that the expression of male sexual ornamentation and associated sperm characteristics depend on an individual’s ability to cope with oxidative stress. Carotenoids are known for their antioxidant properties and carotenoid-based ornaments might represent honest signals as these pigments can be traded off between the investment in sexual ornamentation, sperm function as well as immune response. In this study, we examined the relationship between sexual ornamentation (breeding coloration) and sperm characteristics (e.g., velocity and morphology) in the three-spined stickleback Gasterosteus aculeatus, an externally fertilising fish species, in which sperm competition commonly occurs. During the breeding season males are sperm limited and develop a conspicuous carotenoid-based coloration, which is under strong pre-copulatory sexual selection due to female mate choice and male-male competition. The results of the present study show that the expression of stickleback male breeding coloration is significantly positively associated with the linearity of sperm movement, whereas sperm morphology (head length to tail length ratio) is significantly negatively related to the trajectory of sperm movement. Moreover, there is some support for the phenotype-linked fertility hypothesis as the intensity of male red breeding coloration is significantly positively correlated with sperm velocity, which is supposed to be an important determinant of fertilisation success in external fertilisers, indicating the honesty of the sexually selected nuptial red coloration.

APA, Harvard, Vancouver, ISO, and other styles

44

Stevens, Martin, Annette C. Broderick, Brendan J. Godley, Alice E. Lown, Jolyon Troscianko, Nicola Weber, and Sam B. Weber. "Phenotype–environment matching in sand fleas." Biology Letters 11, no. 8 (August 2015): 20150494. http://dx.doi.org/10.1098/rsbl.2015.0494.

Full text

Abstract:

Camouflage is perhaps the most widespread anti-predator strategy in nature, found in numerous animal groups. A long-standing prediction is that individuals should have camouflage tuned to the visual backgrounds where they live. However, while several studies have demonstrated phenotype–environment associations, few have directly shown that this confers an improvement in camouflage, particularly with respect to predator vision. Here, we show that an intertidal crustacean, the sand flea ( Hippa testudinaria ), has coloration tuned to the different substrates on which it occurs when viewed by potential avian predators. Individual sand fleas from a small, oceanic island (Ascension) matched the colour and luminance of their own beaches more closely than neighbouring beaches to a model of avian vision. Based on past work, this phenotype–environment matching is likely to be driven through ontogenetic changes rather than genetic adaptation. Our work provides some of the first direct evidence that animal coloration is tuned to provide camouflage to prospective predators against a range of visual backgrounds, in a population of animals occurring over a small geographical range.

APA, Harvard, Vancouver, ISO, and other styles

45

Stoddard, Mary Caswell, and Mark E. Hauber. "Colour, vision and coevolution in avian brood parasitism." Philosophical Transactions of the Royal Society B: Biological Sciences 372, no. 1724 (May 22, 2017): 20160339. http://dx.doi.org/10.1098/rstb.2016.0339.

Full text

Abstract:

The coevolutionary interactions between avian brood parasites and their hosts provide a powerful system for investigating the diversity of animal coloration. Specifically, reciprocal selection pressure applied by hosts and brood parasites can give rise to novel forms and functions of animal coloration, which largely differ from those that arise when selection is imposed by predators or mates. In the study of animal colours, avian brood parasite–host dynamics therefore invite special consideration. Rapid advances across disciplines have paved the way for an integrative study of colour and vision in brood parasite–host systems. We now know that visually driven host defences and host life history have selected for a suite of phenotypic adaptations in parasites, including mimicry, crypsis and supernormal stimuli. This sometimes leads to vision-based host counter-adaptations and increased parasite trickery. Here, we review vision-based adaptations that arise in parasite–host interactions, emphasizing that these adaptations can be visual/sensory, cognitive or phenotypic in nature. We highlight recent breakthroughs in chemistry, genomics, neuroscience and computer vision, and we conclude by identifying important future directions. Moving forward, it will be essential to identify the genetic and neural bases of adaptation and to compare vision-based adaptations to those arising in other sensory modalities. This article is part of the themed issue ‘Animal coloration: production, perception, function and application’.

APA, Harvard, Vancouver, ISO, and other styles

46

Jablonski, Nina G., and George Chaplin. "The colours of humanity: the evolution of pigmentation in the human lineage." Philosophical Transactions of the Royal Society B: Biological Sciences 372, no. 1724 (May 22, 2017): 20160349. http://dx.doi.org/10.1098/rstb.2016.0349.

Full text

Abstract:

Humans are a colourful species of primate, with human skin, hair and eye coloration having been influenced by a great variety of evolutionary forces throughout prehistory. Functionally naked skin has been the physical interface between the physical environment and the human body for most of the history of the genus Homo , and hence skin coloration has been under intense natural selection. From an original condition of protective, dark, eumelanin-enriched coloration in early tropical-dwelling Homo and Homo sapiens , loss of melanin pigmentation occurred under natural selection as Homo sapiens dispersed into non-tropical latitudes of Africa and Eurasia. Genes responsible for skin, hair and eye coloration appear to have been affected significantly by population bottlenecks in the course of Homo sapiens dispersals. Because specific skin colour phenotypes can be created by different combinations of skin colour–associated genetic markers, loss of genetic variability due to genetic drift appears to have had negligible effects on the highly redundant genetic ‘palette’ for the skin colour. This does not appear to have been the case for hair and eye coloration, however, and these traits appear to have been more strongly influenced by genetic drift and, possibly, sexual selection. This article is part of the themed issue ‘Animal coloration: production, perception, function and application’.

APA, Harvard, Vancouver, ISO, and other styles

47

Flood, Nancy J. "Coloration in New World orioles." Behavioral Ecology and Sociobiology 25, no. 1 (July 1989): 49–56. http://dx.doi.org/10.1007/bf00299710.

Full text

APA, Harvard, Vancouver, ISO, and other styles

48

Siefferman, Lynn, Yuan-Jyun Wang, Yi-Ping Wang, and Hsiao-Wei Yuan. "Sexual Dichromatism, Dimorphism, and Condition-Dependent Coloration in Blue-Tailed Bee-Eaters." Condor 109, no. 3 (August 1, 2007): 577–84. http://dx.doi.org/10.1093/condor/109.3.577.

Full text

Abstract:

Abstract Abstract. The Blue-tailed Bee-eater (Merops philippinus) is a cooperatively breeding and socially monogamous member of the Coraciiformes that displays conspicuous coloration and elongated central rectrices (“streamers”). Humans cannot distinguish males from females; both sexes are brightly colored with a chestnut throat patch, a yellow chin, and green body coloration fading into a turquoise-blue rump and tail. We quantified coloration with ultraviolet- (UV) visible spectrometry and measured morphology to determine the extent of sexual dichromatism and dimorphism. Males displayed more exaggerated coloration, longer tail streamers, and were larger than females. Multiple plumage ornaments (measures of plumage coloration and streamer length) were positively correlated in both sexes. Males in better body condition expressed darker chestnut throats and more chromatic green body plumage. Females in better body condition, however, exhibited more chromatic blue rumps and yellow chins. This study represents the first objective description of plumage ornamentation in the order Coraciiformes.

APA, Harvard, Vancouver, ISO, and other styles

49

Nielsen, Matthew E., and Johanna Mappes. "Out in the open: behavior’s effect on predation risk and thermoregulation by aposematic caterpillars." Behavioral Ecology 31, no. 4 (May 20, 2020): 1031–39. http://dx.doi.org/10.1093/beheco/araa048.

Full text

Abstract:

Abstract Warning coloration should be under strong stabilizing selection but often displays considerable intraspecific variation. Opposing selection on color by predators and temperature is one potential explanation for this seeming paradox. Despite the importance of behavior for both predator avoidance and thermoregulation, its role in mediating selection by predators and temperature on warning coloration has received little attention. Wood tiger moth caterpillars, Arctia plantaginis, have aposematic coloration, an orange patch on the black body. The size of the orange patch varies considerably: individuals with larger patches are safer from predators, but having a small patch is beneficial in cool environments. We investigated microhabitat preference by these caterpillars and how it interacted with their coloration. We expected caterpillar behavior to reflect a balance between spending time exposed to maximize basking and spending time concealed to avoid detection by predators. Instead, we found that caterpillars preferred exposed locations regardless of their coloration. Whether caterpillars were exposed or concealed had a strong effect on both temperature and predation risk, but caterpillars in exposed locations were both much warmer and less likely to be attacked by a bird predator (great tits, Parus major). This shared optimum may explain why we observed so little variation in caterpillar behavior and demonstrates the important effects of behavior on multiple functions of coloration.

APA, Harvard, Vancouver, ISO, and other styles

50

Dias, Sidclay Calaça. "Color pattern changes in Pachistopelma rufonigrum Pocock (Araneae, Theraphosidae)." Revista Brasileira de Zoologia 21, no. 1 (March 2004): 153–54. http://dx.doi.org/10.1590/s0101-81752004000100025.

Full text

Abstract:

Pachistopelma rufonigrum Pocock, 1901 presents ontogenetic changes of its coloration pattern throughout its development. After emergence from the eggs, spiderlings are bluish, with metallic and/or iridescent nuances. The juveniles have a vertically directed black stripe in the central region of abdomen dorsum and three horizontally directed black stripes in the abdomen dorsum. Adults are completely black. These coloration differences between juveniles and adults of the same species appear to be a strategy to avoid the intraspecific competition.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Animal coloration'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles