scholarly journals Microstructures amplify carotenoid plumage signals in tanagers

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Dakota E. McCoy ◽  
Allison J. Shultz ◽  
Charles Vidoudez ◽  
Emma van der Heide ◽  
Jacqueline E. Dall ◽  
...  
Keyword(s):  
Optical Power ◽  
Sexually Dimorphic ◽  
Carotenoid Pigments ◽  
Carotenoid Pigment ◽  
Optical Modeling ◽  
Honest Signals ◽  
The Social ◽  
Color Differences ◽  
Saturated Color ◽  
Difference Time

AbstractBrilliantly-colored birds are a model system for research into evolution and sexual selection. Red, orange, and yellow carotenoid-colored plumages have been considered honest signals of condition; however, sex differences in feather pigments and microstructures are not well understood. Here, we show that microstructures, rather than carotenoid pigments, seem to be a major driver of male–female color differences in the social, sexually-dimorphic tanager genus Ramphocelus. We comprehensively quantified feather (i) color (using spectrophotometry), (ii) pigments (using liquid chromatography–mass spectrometry (LC–MS)), and (iii) microstructures (using scanning electron microscopy (SEM) and finite-difference time-domain (FDTD) optical modeling). Males have significantly more saturated color patches than females. However, our exploratory analysis of pigments suggested that males and females have concordant carotenoid pigment profiles across all species (MCMCglmm model, female:male ratio = 0.95). Male, but not female, feathers have elaborate microstructures which amplify color appearance. Oblong, expanded feather barbs in males enhance color saturation (for the same amount of pigment) by increasing the transmission of optical power through the feather. Dihedral barbules (vertically-angled, strap-shaped barbules) in males reduce total reflectance to generate “super black” and “velvet red” plumage. Melanin in females explains some, but not all, of the male–female plumage differences. Our results suggest that a widely cited index of honesty, carotenoid pigments, cannot fully explain male appearance. We propose that males are selected to evolve amplifiers—in this case, microstructures that enhance appearance—that are not necessarily themselves linked to quality.

scholarly journals Microstructures amplify carotenoid plumage signals in colorful tanagers

2019 ◽  
Author(s):  
Dakota E. McCoy ◽  
Allison J. Shultz ◽  
Charles Vidoudez ◽  
Emma van der Heide ◽  
Sunia A. Trauger ◽  
...  
Keyword(s):  
Optical Power ◽  
Sexually Dimorphic ◽  
Carotenoid Pigment ◽  
Liquid Chromatography Mass Spectrometry ◽  
Optical Modeling ◽  
Honest Signals ◽  
The Social ◽  
Males And Females ◽  
Saturated Color ◽  
Difference Time

AbstractRed, orange, and yellow carotenoid-colored plumages have been considered honest signals of condition. We comprehensively quantified carotenoid signals in the social, sexually-dimorphic tanager genus Ramphocelus using scanning electron microscopy (SEM), finite-difference time-domain (FDTD) optical modeling, liquid chromatography–mass spectrometry (LC-MS), and spectrophotometry. Despite males having significantly more saturated color patches, males and females within a species have equivalent amounts and types of carotenoids. Male, but not female, feathers have elaborate microstructures which amplify color appearance. Expanded barbs enhance color saturation (for the same amount of pigment) by increasing the transmission of optical power through the feather. Dihedral barbules (vertically-angled, strap-shaped barbules) reduce total reflectance to generate “super black” plumage, an optical illusion to enhance nearby color. Dihedral barbules paired with red carotenoid pigment produce “velvet red” plumage. Together, our results suggest that a widely cited index of honesty—carotenoid pigments—cannot fully explain male appearance. We propose that males are selected to evolve amplifiers of honest signals—in this case, microstructures that enhance appearance —that are not necessarily themselves linked to quality.

scholarly journals Prenatal Risk for Autism Spectrum Disorder (ASD): Fetal Cortisol Exposure Predicts Child ASD Symptoms

2018 ◽  
Vol 7 (2) ◽  
pp. 349-361 ◽  
Author(s):  
Sheena Ram ◽  
Mariann A. Howland ◽  
Curt A. Sandman ◽  
Elysia Poggi Davis ◽  
Laura M. Glynn
Keyword(s):  
Autism Spectrum Disorder ◽  
Developmental Disorder ◽  
Maternal Plasma ◽  
Autism Spectrum ◽  
Spectrum Disorder ◽  
Sexually Dimorphic ◽  
Fetal Exposure ◽  
Prospective Longitudinal Study ◽  
The Social ◽  
Prospective Longitudinal

The etiology of autism spectrum disorder (ASD) is multifactorial, complex, and likely involves interactions among genetic, epigenetic, and environmental factors. With respect to environmental influences, a growing literature implicates intrauterine experiences in the origin of this pervasive developmental disorder. In this prospective longitudinal study, we examined the hypothesis that fetal exposure to maternal cortisol may confer ASD risk. In addition, because ASD is four times more prevalent in males than in females, and because sexually dimorphic responses to intrauterine experiences are commonly observed, we examined whether or not any associations differ by fetal sex. Maternal plasma cortisol was measured at 15, 19, 25, 31, and 37 weeks’ gestation in a sample of 84 pregnant women. ASD symptoms were assessed in their 5-year-old children with the Social Communication Questionnaire (SCQ). Fetal exposure to lower levels of maternal cortisol was associated with higher levels of ASD symptoms only among boys. The observed hypocortisolemic profile exhibited by these mothers may indicate a risk factor that precedes the stress of caregiving for a child with ASD and may not be solely a consequence of the stress of caregiving, as previously thought. These findings confirm the value of examining prenatal hormone exposures as predictors of ASD risk and support the premise that altered prenatal steroid exposures may play a role in the etiology of ASD.

scholarly journals Heightened condition dependent expression of structural colouration in the faces, but not wings, of male and female flies

2021 ◽  
Author(s):  
Thomas E White ◽  
Amy Locke ◽  
Tanya Latty
Keyword(s):  
Mate Choice ◽  
Condition Dependence ◽  
Sexually Dimorphic ◽  
Male And Female ◽  
Honest Signals ◽  
Mutual Mate Choice ◽  
Close Range ◽  
Males And Females ◽  
Structural Colouration

Abstract Structurally coloured sexual signals are a conspicuous and widespread class of ornament used in mate choice, though the extent to which they encode information on the quality of their bearers is not fully resolved. Theory predicts that signalling traits under strong sexual selection as honest indicators should evolve to be more developmentally integrated and exaggerated than nonsexual traits, thereby leading to heightened condition dependence. Here we test this prediction through examination of the sexually dimorphic faces and wings of the cursorial fly Lispe cana. Males and females possess structural UV-white and golden faces, respectively, and males present their faces and wings to females during close-range, ground-based courtship displays, thereby creating the opportunity for mutual inspection. Across a field-collected sample of individuals, we found that the appearance of the faces of both sexes scaled positively with individual condition, though along separate axes. Males in better condition expressed brighter faces as modelled according to conspecific flies, whereas condition scaled with facial saturation in females. We found no such relationships for their wing interference pattern nor abdomens, with the latter included as a nonsexual control. Our results suggest that the structurally coloured faces, but not the iridescent wings, of male and female Lispe cana are reliable guides to individual quality and support the broader potential for structural colours as honest signals. They also highlight the potential for mutual mate choice in this system, while arguing for one of several alternate signalling roles for wing interferences patterns among the myriad taxa which bear them.

scholarly journals Analysis of Carotenoid Pigment Types in the Carapace of the Male Crab Grapsus albolinetaus Latreille in Milbert 1812

2021 ◽  
Vol 9 (1) ◽  
pp. 132
Author(s):  
Fatika Sari Mokoginta ◽  
Darus Saadah Johanis Paransa ◽  
Kurnati Kemer ◽  
James J. H. Paulus ◽  
Nickson J. Kawung ◽  
...  
Keyword(s):  
Stationary Phase ◽  
Column Chromatography ◽  
Metabolic Pathways ◽  
Mobile Phase ◽  
Separation Technique ◽  
Carotenoid Pigments ◽  
Carotenoid Pigment ◽  
Silica Powder ◽  
Male Crab ◽  
Yellow Orange

Carotenoid pigments have various colors such as yellow, orange, or red-orange. One of the carotenoid pigment sources is Crab G. albolineatus Latreille in Milbert 1812. Column chromatography separation technique was used to determine the metabolism of carotenoid pigments in the crab G. albolineatus latreille in Milbert 1812. This CC separation used hexane and acetone as the developer solution (70:30). The developer solution as known as the mobile phase is semipolar, while the stationary phase is silica powder G60. Therefore, it formed two metabolic pathways. The male G. albolineatus crab used in this study was on the D3 molting stage which had a concentration of 36.37 g/g dry residue and 4.72 g content. The types of pigments identified are: β – karoten, Zeaxanthin, lutein, β – kriptoxanthin dan Astaxanthin.Keywords: Carotenoid Pigments; G. albolineatus; Column Chromatography; MoltingAbstrakPigmen karotenoid memiliki berbagai warna seperti kuning, oranye, atau merah oranye. Salah satu sumber pigmen karotenoid adalah pada karapas kepiting G. albolineatus Latreille in Milbert 1812. Untuk mengetahui metabolisme jenis pigmen karotenoid pada kepiting Grapsus albolineatus latreille in Milbert 1812 yaitu menggunakan pemisahan kromatografi Kolom. Pemisahan KK ini menggunakan larutan pengembang heksan dan aseton (70:30). Larutan pengembang merupakan fase gerak yang bersifat semipolar dan fase diamnya menggunakan bubuk silika G60. Terbentuk dua  jalur metabolisme. Kepiting G. albolineatus jantan yang digunakan pada penelitian berada di stadium molting D3 dengan konsentrasi sebesar 36,37 µg/g berat residu kering dan kandungan 4,72 µg. Jenis pigmen yang teridentifikasi yaitu : β – karoten, Zeaxanthin, lutein, β – kriptoxanthin dan Astaxanthin.Kata kunci: Pigmen; Karotenoid; G. albolineatus; Kromatofrafi Kolom; Molting

Spatial variability in the social organisation of the yellow-bellied glider (Petaurus australis) near Ravenshoe, north Queensland

2001 ◽  
Vol 49 (4) ◽  
pp. 397 ◽  
Author(s):  
Ross L. Goldingay ◽  
Darren G. Quin ◽  
Sue Churchill
Keyword(s):  
Adult Female ◽  
Social System ◽  
Dominant Male ◽  
Female Group ◽  
Sexually Dimorphic ◽  
Adult Males ◽  
Adult Females ◽  
The Social ◽  
Natal Home ◽  
Petaurus Australis

A detailed study was conducted over a 12-month period of 10 yellow-bellied glider groups at Nitchaga Creek in north Queensland. Adult gliders were sexually dimorphic in body size and were characterised by yellow ventral fur, which is consistent with southern populations. Gliders lived in groups of 3–6 individuals that occupied exclusive areas of about 50 ha. The structure of glider groups varied enormously: five contained one adult pair, three contained one adult male and 2–3 adult females, and two initially contained 2–3 adult males and one adult female but then persisted as bachelor groups after the death or disappearance of the adult female. Group size changed during the year as offspring matured and as individuals died. One male glider dispersed about 1 km from its natal home-range and became the dominant male in a nearby group. Young were born throughout the year, with a peak in the number of pouch-young in June. This study has confirmed the highly variable social system of the yellow-bellied glider, which appears to be mediated by local resource abundance.

scholarly journals Facial Feminization Surgery Changes Perception of Patient Gender

2019 ◽  
Vol 40 (7) ◽  
pp. 703-709 ◽  
Author(s):  
Mark Fisher ◽  
Stephen M Lu ◽  
Kevin Chen ◽  
Ben Zhang ◽  
Marcelo Di Maggio ◽  
...  
Keyword(s):  
Hormone Therapy ◽  
Online Survey ◽  
Confidence Score ◽  
Sexually Dimorphic ◽  
Level Of Evidence ◽  
Female Hormone ◽  
The Public ◽  
Patient Gender ◽  
The Social ◽  
The Face

Abstract Background The goal of facial feminization surgery (FFS) is to feminize the sexually dimorphic characteristics of the face and enable transwomen to be correctly gendered as female. Studies have demonstrated high patient satisfaction with FFS. However, the correct gendering of patients after FFS has never been objectively studied. Objectives The aim of this study was to determine if FFS changed the perceived gender of patients in the public eye. Methods An online survey platform with control photographs of cis-gender males and cis-gender females as well as preoperative and postoperative FFS patients was created. Respondents were asked to identify patients as “male” or “female” and to assign a confidence score ranging from –10 (masculine) to +10 (feminine) (n = 802). Results Cis-gender male and female controls were gendered correctly 99% and 99.38% of the time and with a confidence metric (CM) of –8.96 and 8.93, respectively. Preoperative FFS patients were gendered as female 57.31% of the time with a CM of 1.41 despite hormone therapy, makeup, and hairstyle. Postoperative FFS patients were gendered as female 94.27% of the time with a CM of 7.78. Ninety-five percent of patients showed a significant improvement in CM after FFS. Conclusions This study illustrates that FFS changes the social perception of a patient’s gender. Patients after FFS are more likely to be identified as female and with greater confidence than before surgery. This is despite preoperative female hormone therapy, and nonsurgical methods that patients use to feminize their appearance. Level of Evidence: 4

Depth Distribution of the Carotenoid Pigments and Lipids of Some Oceanic Animals 1. Mixed Zooplankton, Copepods and Euphausiids

1972 ◽  
Vol 52 (1) ◽  
pp. 179-189 ◽  
Author(s):  
Peter J. Herring
Keyword(s):  
Lipid Content ◽  
Depth Distribution ◽  
Carotenoid Pigments ◽  
Carotenoid Pigment ◽  
Protective Coloration ◽  
Close Relationship ◽  
Different Depths ◽  
Pigment Concentrations ◽  
Depth Ranges ◽  
Related Increase

Analysis of the carotenoid pigment and lipid concentrations of groups of the smaller zooplankton organisms from different depths has suggested a midwater maximum for carotenoid concentrations and a slight depth-related increase in lipid content. Similar analysis of seventeen species of euphausiid has not indicated similar trends, but has shown a close relationship between size and pigment content in all species other than those ofStylocheiron,which have significantly lower pigment concentrations. Comparisons of the data of Fisher, Kon & Thompson (1964) on the pigment and lipid concentrations of copepods with the known depth ranges of the various species have suggested a midwater maximum in pigment concentrations, but no consistent trends in the lipid concentrations. A midwater pigment peak is explicable in terms of pigment accessibility and requirement for protective coloration, and the significance of the pigments is discussed.

scholarly journals Oil droplets of bird eyes: microlenses acting as spectral filters

2014 ◽  
Vol 369 (1636) ◽  
pp. 20130041 ◽  
Author(s):  
Doekele G. Stavenga ◽  
Bodo D. Wilts
Keyword(s):  
Narrow Band ◽  
Carotenoid Pigments ◽  
Carotenoid Pigment ◽  
Spectral Filtering ◽  
Quantitative Modelling ◽  
Oil Droplets ◽  
Spectral Filters ◽  
Spectral Discrimination ◽  
Light Loss ◽  
High Concentrations

An important component of the cone photoreceptors of bird eyes is the oil droplets located in front of the visual-pigment-containing outer segments. The droplets vary in colour and are transparent, clear, pale or rather intensely yellow or red owing to various concentrations of carotenoid pigments. Quantitative modelling of the filter characteristics using known carotenoid pigment spectra indicates that the pigments’ absorption spectra are modified by the high concentrations that are present in the yellow and red droplets. The high carotenoid concentrations not only cause strong spectral filtering but also a distinctly increased refractive index at longer wavelengths. The oil droplets therefore act as powerful spherical microlenses, effectively channelling the spectrally filtered light into the photoreceptor's outer segment, possibly thereby compensating for the light loss caused by the spectral filtering. The spectral filtering causes narrow-band photoreceptor spectral sensitivities, which are well suited for spectral discrimination, especially in birds that have feathers coloured by carotenoid pigments.

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