Article
Multidisciplinary Sciences
Willow R. Lindsay, Rute Mendonca, Mathilda Waleij Slight, Maria Prager, Mats X. Andersson, Nicholas I. Mundy, Staffan Andersson
Summary: Intense red colours in birds are often caused by ketocarotenoids. The expression of CYP2J19 gene in southern red bishop birds is related to season, sex, moult, body condition and sex steroids, but not plumage redness or male body condition.
ROYAL SOCIETY OPEN SCIENCE
(2022)
Article
Evolutionary Biology
Lisandro T. Bazzano, Lucas R. Mendicino, Marina E. Inchaussandague, Diana C. Skigin, Natalia C. Garcia, Pablo L. Tubaro, Ana S. Barreira
Summary: The non-iridescent, structural coloration in birds is influenced by the internal nanostructure of feathers, as well as melanin pigments and the characteristics of the barb's cortex. In this study, the association between light reflectance and feather morphology was investigated in differently colored plumage patches of male swallow tanagers. The color differences between the greenish-blue and white plumage were found to be primarily due to variations in melanin deposition and the reduction of the spongy matrix near the rachis of the belly feather barbs, rather than changes in the spongy matrix itself.
JOURNAL OF EXPERIMENTAL ZOOLOGY PART B-MOLECULAR AND DEVELOPMENTAL EVOLUTION
(2021)
Article
Ornithology
Natalia C. Garcia, Ana S. Barreira, Pablo L. Tubaro
Summary: This study investigated the relationship between sexual dichromatism and color features in the Cardinalidae bird family. The results showed that sexual dichromatism levels were not strongly correlated with colorfulness or conspicuousness against the background.
Article
Ecology
Maria Cecilia Chiale, Miguel A. Rendon, Sophie Labaude, Anne-Sophie Deville, Juan Garrido-Fernandez, Antonio Perez-Galvez, Araceli Garrido, Manuel Rendon-Martos, Arnaud Bechet, Juan A. Amat
Summary: Greater flamingos use cosmetic coloration by spreading pigmented uropygial secretions over their feathers to make them redder. Experimental exposure to sunlight resulted in fading of feather color, indicating the need for regular application of makeup to maintain colorful plumage.
ECOLOGY AND EVOLUTION
(2021)
Article
Biochemistry & Molecular Biology
Diego Ocampo, Kevin Winker, Matthew J. Miller, Luis Sandoval, J. Albert C. Uy
Summary: Differences in plumage coloration are maintained by divergent selection, but are insufficient to maintain reproductive isolation. Populations with divergent phenotypes hybridize extensively in one contact zone but not in another, indicating that plumage divergence alone is insufficient to maintain reproductive isolation. Hybrid zones are wide and formed by later-generation hybrids, suggesting frequent reproduction and high survivorship for hybrid individuals. Contemporary gene flow has played an important role in shaping genetic structure between populations.
Article
Biology
M. Y. Goretskaia, I. R. Beme
Summary: The research over more than 50 years has analyzed the role of testosterone in passerine birds, discussing its influence on various aspects of bird behavior and physiology. The study also examines the role of testosterone in regulating aggressive behavior, immune function, and the development of sexual traits in birds.
Article
Ornithology
Yingqiang Lou, Lijun Chen, Qingshan Zhao, Anders Pape Moller, Yun Fang, Yuehua Sun
Summary: Study finds that in Chestnut Thrushes, female birds had better body condition than males, and female behavior was associated with lower chroma of their back plumage while male behavior was associated with lower red chroma of their brown back plumage. However, plumage coloration did not explain variation in exploratory behavior.
Article
Biochemistry & Molecular Biology
Ana Paula Machado, Tristan Cumer, Christian Iseli, Emmanuel Beaudoing, Anne-Lyse Ducrest, Melanie Dupasquier, Nicolas Guex, Klaus Dichmann, Rui Lourenco, John Lusby, Hans-Dieter Martens, Laure Prevost, David Ramsden, Alexandre Roulin, Jerome Goudet
Summary: Research suggests that barn owls colonized the British Isles directly from a white-colored refugium in the Iberian Peninsula after the last glaciation, rather than crossing over Doggerland as previously believed. They maintained their white color in the British Isles through low gene flow with the mainland, suggesting neutral processes rather than selection for the contrasting color. This unexpected colonization route may have implications for other species from the paleo community as well.
Article
Ecology
Gabriel Macedo, Rafael S. Marcondes, Cibele Biondo, Gustavo A. Bravo, Elizabeth P. Derryberry
Summary: Selection on signals is affected by resource availability, which is regulated by climate. Harsher environments may lead to convergent development of signals in both sexes, increasing sexual dimorphism.
Article
Ecology
Diego F. Beltran, Allison J. Shultz, Juan L. Parra
Summary: The uneven distribution of biodiversity among different clades in nature shows that communication signals, such as plumage coloration in hummingbirds, play a crucial role in speciation. The study on 237 hummingbird species reveals that color evolution rates are associated with speciation rates, particularly in male plumage patches, suggesting an interplay between natural and sexual selection in driving speciation.
Article
Agricultural Engineering
Xiaowei Zhu, Tianchen Wei, Matthew D. Shawkey, Tieling Xing, Guoqiang Chen
Summary: Utilizing caffeic acid for the fabrication of structurally colored nanospheres, the resulting fabrics exhibit vibrant colors and remarkable durability, suitable for various laundering and abrasion tests.
INDUSTRIAL CROPS AND PRODUCTS
(2022)
Article
Environmental Sciences
Yong Song, Katherine Southam, Ellen Bennett, Fay Johnston, Lisa Foa, Amanda J. Wheeler, Graeme R. Zosky
Summary: The study found that gestational exposure to residential roof space PM during pregnancy affects body weight and brain development in post-natal mice, particularly leading to increased myelin load in the white matter and elevated microglial density.
ENVIRONMENTAL RESEARCH
(2021)
Article
Psychiatry
Leo Sher, Linda M. Bierer, Iouri Makotkine, Rachel Yehuda
Summary: The study found significant differences in testosterone levels between suicide attempters and non-attempters, with attempters having higher suicidal ideation scores and lower baseline testosterone levels. Dexamethasone administration had no significant impact on free testosterone levels among attempters, and post-dexamethasone free testosterone levels positively correlated with aggression scores among non-attempters.
JOURNAL OF PSYCHIATRIC RESEARCH
(2021)
Article
Plant Sciences
Wanwan Zhang, Yifang Wei, Xiaoxiao Cao, Kaixin Guo, Qiangqiang Wang, Xiaochun Xiao, Xufeng Zhai, Dingding Wang, Zebo Huang
Summary: The Crassostrea oyster peptide preparation COP3 has shown promising effects in increasing testosterone and cAMP levels in male mice, enhancing NOS activity in the penile region, and stimulating testosterone and NO production in Leydig-derived cells. Its upregulation of genes associated with sex hormone secretion pathways and a conserved steroidogenic enzyme suggests its potential in addressing erectile dysfunction.
JOURNAL OF ETHNOPHARMACOLOGY
(2021)
Article
Multidisciplinary Sciences
Mari-Ann Lind, Tuul Sepp, Kristiina Stseglova, Peeter Horak
Summary: Carotenoid plumage coloration in greenfinches is affected by the antibiotic METRO, leading to significantly higher chroma of yellow parts in feathers grown during the experiment.
SCIENTIFIC REPORTS
(2021)
Article
Zoology
Geoffrey E. Hill
INTEGRATIVE AND COMPARATIVE BIOLOGY
(2019)
Review
Ecology
Lynn B. Martin, BriAnne Addison, Andrew G. D. Bean, Katherine L. Buchanan, Ondi L. Crino, Justin R. Eastwood, Andrew S. Flies, Rodrigo Hamede, Geoffrey E. Hill, Marcel Klaassen, Rebecca E. Koch, Johanne M. Martens, Constanza Napolitano, Edward J. Narayan, Lee Peacock, Alison J. Peel, Anne Peters, Nynke Raven, Alice Risely, Michael J. Roast, Lee A. Rollins, Manuel Ruiz-Aravena, Dan Selechnik, Helena S. Stokes, Beata Ujvari, Laura F. Grogan
TRENDS IN ECOLOGY & EVOLUTION
(2019)
Article
Zoology
Wendy R. Hood, Ashley S. Williams, Geoffrey E. Hill
INTEGRATIVE AND COMPARATIVE BIOLOGY
(2019)
Article
Psychology, Biological
Matthew J. Powers, Geoffrey E. Hill, Ryan J. Weaver
Article
Ecology
Nicholas M. Justyn, Corey T. Callaghan, Geoffrey E. Hill
Review
Genetics & Heredity
Geoffrey E. Hill
TRENDS IN GENETICS
(2020)
Article
Ecology
Geoffrey E. Hill
ECOLOGY AND EVOLUTION
(2020)
Article
Marine & Freshwater Biology
Matthew J. Powers, Ryan J. Weaver, Kyle B. Heine, Geoffrey E. Hill
Review
Zoology
Matthew J. Powers, Geoffrey E. Hill
Summary: For decades, scientists have observed a connection between carotenoid-based coloration and an organism's physiological performance and behavior. Traditional explanations for this relationship suggest that colorful displays are costly, but an alternative explanation, the Shared-Pathway Hypothesis, proposes that carotenoid-based coloration is linked to mitochondrial energy metabolism. Empirical tests have been conducted to investigate this hypothesis in various species.
INTEGRATIVE AND COMPARATIVE BIOLOGY
(2021)
Editorial Material
Ecology
Geoffrey E. Hill, Nicholas M. Justyn
Summary: Estimating per-individual rates of hybridization in wild birds involves challenges related to the definition of hybrid, distinguishing between shared DNA sequences and ongoing hybridization, the dangers of focusing only on known hybrid zones, and the implications of very low rates of per individual hybridization. Recognizing hybrids based on phenotype, quantifying ongoing between-species mating, and not prejudging which birds are presumed to engage in hybridization are important considerations in this field. Additionally, evidence for strong prezygotic sorting does not necessarily indicate that mate choice drives speciation.
Article
Ornithology
Geoffrey E. Hill, Matthew Powers
Summary: The process of speciation remains poorly understood, with definitions of species continuing to be a focus of debate. The unresolved issue of whether local populations somewhat distinct from a parent population but connected via gene flow should be recognized as species is a key point in speciation debates. The recognition of the Cassia crossbill, parrot crossbill, and Scottish crossbill as species is argued against, as they do not meet the criteria for species designation under the Biological Species Concept and show no fixed genetic differences from other red crossbill populations.
JOURNAL OF AVIAN BIOLOGY
(2021)
Editorial Material
Ecology
Nicholas M. Justyn, Corey T. Callaghan, Geoffrey E. Hill
Summary: When working with a citizen science database like eBird, it is important to be cautious when filtering or subsampling observations to avoid potential biases. Restricting observations based on specific criteria may inflate the calculated hybridization rate and assume researchers have complete knowledge of birds' hybridization capacity.
Article
Biology
Matthew J. Powers, James A. Baty, Alexis M. Dinga, James H. Mao, Geoffrey E. Hill
Summary: The shared-pathway hypothesis suggests that ketocarotenoid pigmentation and mitochondrial function are biochemically interconnected. This study exposed Tigriopus californicus copepods to DNP and found that it increased respiration and ketocarotenoid accumulation. The results support the hypothesis and suggest a fundamental connection between ketocarotenoid pigmentation and mitochondrial function.
JOURNAL OF EXPERIMENTAL BIOLOGY
(2022)
Article
Biology
Geoffrey E. Hill, Ryan J. Weaver, Matthew J. Powers
Summary: The deposition of carotenoids resulting in red and yellow coloration is an honest signal of condition. The resource trade-off hypothesis suggests that condition-dependent honest signalling depends on a trade-off between ornamental display and body maintenance, while the index hypothesis proposes that carotenoid coloration is inherently condition dependent due to vital cellular processes. These hypotheses have contrasting and testable predictions about ornamental traits. Reviewing mechanisms of carotenoid production, condition dependency patterns, and behavioral responses to carotenoid coloration provides evidence for the existence of condition-dependent signals without the influence of sexual selection. Genetic manipulation and expression of ornamental traits in synthetic biological systems open up new opportunities for studying condition-dependent signaling.
BIOLOGICAL REVIEWS
(2023)
Article
Multidisciplinary Sciences
Nicholas M. Justyn, Kyle B. Heine, Wendy R. Hood, Jennifer A. Peteya, Bram Vanthournout, Gerben Debruyn, Matthew D. Shawkey, Ryan J. Weaver, Geoffrey E. Hill
Summary: This study investigated the formation mechanism of red eyespots in Tigriopus californicus copepods and found that the red eyespots are the result of a combination of structural and pigmentary coloration.
JOURNAL OF THE ROYAL SOCIETY INTERFACE
(2022)