scholarly journals Divergent color signals from homologous unfeathered ornaments in two congeneric grouse

2019 ◽  
Vol 9 (20) ◽  
pp. 11833-11847 ◽  
Author(s):  
Geoffrey M. Gould ◽  
Gerald G. Carter ◽  
Jacqueline K. Augustine
Keyword(s):  
Color Signals

Fully compatible EDTV for improving both Y and color signals by using a single new subcarrier

1988 ◽  
Vol 34 (3) ◽  
pp. 469-473 ◽  
Author(s):  
T. Fukinuki ◽  
Y. Hirano ◽  
H. Yoshigi ◽  
N. Suzuki
Keyword(s):  
Color Signals

scholarly journals Self-recognition, color signals, and cycles of greenbeard mutualism and altruism

2006 ◽  
Vol 103 (19) ◽  
pp. 7372-7377 ◽  
Author(s):  
B. Sinervo ◽  
A. Chaine ◽  
J. Clobert ◽  
R. Calsbeek ◽  
L. Hazard ◽  
...  
Keyword(s):  
Self Recognition ◽  
Color Signals

scholarly journals Male characteristics as predictors of genital color and display variation in vervet monkeys

2020 ◽  
Vol 74 (2) ◽  
Author(s):  
Mirjam M. I. Young ◽  
Sandra Winters ◽  
Christopher Young ◽  
Brigitte M. Weiß ◽  
Jolyon Troscianko ◽  
...  
Keyword(s):  
Color Variation ◽  
Male Dominance ◽  
Primate Species ◽  
Vervet Monkeys ◽  
Color Analysis ◽  
Visual Modeling ◽  
Modeling Methods ◽  
Chlorocebus Pygerythrus ◽  
Color Signals ◽  
Behavioral Display

Abstract In the animal kingdom, conspicuous colors are often used for inter- and intra-sexual communication. Even though primates are the most colorful mammalian taxon, many questions, including what potential information color signals communicate to social partners, are not fully understood. Vervet monkeys (Chlorocebus pygerythrus) are ideal to examine the covariates of color signals. Males have multi-colored genitals, which they present during distinctive male-male interactions, known as the “Red-White-and-Blue” (RWB) display, but the genitals are also visible across a variety of other contexts, and it is unclear what this color display signals to recipients. We recorded genital color presentations and standardized digital photos of male genitals (N = 405 photos) over one mating season for 20 adult males in three groups at the Samara Private Game Reserve, South Africa. We combined these with data on male characteristics (dominance, age, tenure length, injuries, and fecal glucocorticoid metabolite concentrations). Using visual modeling methods, we measured single colors (red, white, blue) but also the contrasts between colors. We assessed the frequency of the RWB genital display and male variation in genital coloration and linked this to male characteristics. Our data suggest that the number of genital displays increased with male dominance. However, none of the variables investigated explained the inter- and intra-individual variation in male genital coloration. These results suggest that the frequency of the RWB genital display, but not its color value, is related to dominance, providing valuable insights on covariation in color signals and their display in primates. Significance statement Conspicuous colors in animals often communicate individual quality to mates and rivals. By investigating vervet monkeys, a primate species in which males present their colorful genitals within several behavioral displays, we aim to identify the covariates of such colorful signals and their behavioral display. Using visual modeling methods for the color analysis and combining behavioral display data and color data with male characteristics, we found that high-ranking males displayed their colorful genitals more frequently than lower-ranking ones. In contrast, color variation was not influenced by male dominance, age, tenure length, or health. Our results can serve as a basis for future investigations on the function of colorful signals and behavioral displays, such as a badge of status or mate choice in primates.

Three-Dimensional Spectrum and Processing of Digital NTSC Color Signals

SMPTE Journal ◽  
1982 ◽  
Vol 91 (4) ◽  
pp. 372-378 ◽  
Author(s):  
E. Dubois ◽  
M. S. Sabri ◽  
J.-Y. Ouellet
Keyword(s):  
Three Dimensional ◽  
Dimensional Spectrum ◽  
Color Signals

Lie methods for color robot vision

Robotica ◽  
2008 ◽  
Vol 26 (4) ◽  
pp. 453-464 ◽  
Author(s):  
Reiner Lenz
Keyword(s):  
Color Image ◽  
Robot Vision ◽  
Image Sequences ◽  
Color Changes ◽  
Integrable Functions ◽  
Conical Section ◽  
Lie Methods ◽  
Color Signals ◽  
Half Axis ◽  
Square Integrable Functions

SUMMARYWe describe how Lie-theoretical methods can be used to analyze color related problems in machine vision. The basic observation is that the nonnegative nature of spectral color signals restricts these functions to be members of a limited, conical section of the larger Hilbert space of square-integrable functions. From this observation, we conclude that the space of color signals can be equipped with a coordinate system consisting of a half-axis and a unit ball with the Lorentz groups as natural transformation group. We introduce the theory of the Lorentz group SU(1, 1) as a natural tool for analyzing color image processing problems and derive some descriptions and algorithms that are useful in the investigation of dynamical color changes. We illustrate the usage of these results by describing how to compress, interpolate, extrapolate, and compensate image sequences generated by dynamical color changes.

Consistent Associations between Body Size and Hidden Contrasting Color Signals across a Range of Insect Taxa

2019 ◽  
Vol 194 (1) ◽  
pp. 28-37 ◽  
Author(s):  
Karl Loeffler-Henry ◽  
Changku Kang ◽  
Thomas N. Sherratt
Keyword(s):  
Body Size ◽  
Color Signals

scholarly journals Chemical Basis of Floral Color Signals in Gesneriaceae: The Effect of Alternative Anthocyanin Pathways

2020 ◽  
Vol 11 ◽  
Author(s):  
Ezgi Ogutcen ◽  
Karine Durand ◽  
Marina Wolowski ◽  
Laura Clavijo ◽  
Catherine Graham ◽  
...  
Keyword(s):  
High Performance ◽  
Flower Color ◽  
Pollination Syndromes ◽  
Angiosperm Evolution ◽  
Ecological Diversification ◽  
Floral Color ◽  
Wide Range ◽  
Hummingbird Pollination ◽  
Color Signals ◽  
Physical And Chemical

Changes in floral pigmentation can have dramatic effects on angiosperm evolution by making flowers either attractive or inconspicuous to different pollinator groups. Flower color largely depends on the type and abundance of pigments produced in the petals, but it is still unclear whether similar color signals rely on same biosynthetic pathways and to which extent the activation of certain pathways influences the course of floral color evolution. To address these questions, we investigated the physical and chemical aspects of floral color in the Neotropical Gesnerioideae (ca. 1,200 spp.), in which two types of anthocyanins, hydroxyanthocyanins, and deoxyanthocyanins, have been recorded as floral pigments. Using spectrophotometry, we measured flower reflectance for over 150 species representing different clades and pollination syndromes. We analyzed these reflectance data to estimate how the Gesnerioideae flowers are perceived by bees and hummingbirds using the visual system models of these pollinators. Floral anthocyanins were further identified using high performance liquid chromatography coupled to mass spectrometry. We found that orange/red floral colors in Gesnerioideae are produced either by deoxyanthocyanins (e.g., apigenidin, luteolinidin) or hydroxyanthocyanins (e.g., pelargonidin). The presence of deoxyanthocyanins in several lineages suggests that the activation of the deoxyanthocyanin pathway has evolved multiple times in the Gesnerioideae. The hydroxyanthocyanin-producing flowers span a wide range of colors, which enables them to be discriminated by hummingbirds or bees. By contrast, color diversity among the deoxyanthocyanin-producing species is lower and mainly represented at longer wavelengths, which is in line with the hue discrimination optima for hummingbirds. These results indicate that Gesnerioideae have evolved two different biochemical mechanisms to generate orange/red flowers, which is associated with hummingbird pollination. Our findings also suggest that the activation of the deoxyanthocyanin pathway has restricted flower color diversification to orange/red hues, supporting the potential constraining role of this alternative biosynthetic pathway on the evolutionary outcome of phenotypical and ecological diversification.

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