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Impairment of mixed melanin-based pigmentation in parrots

Parrots and allies (Order Psittaciformes) have evolved an exclusive capacity to synthesize polyene pigments called psittacofulvins at feather follicles, which allows them to produce a striking diversity of pigmentation phenotypes. Melanins are polymers constituting the most abundant pigments in animals, and the sulphurated form (pheomelanin) produces colors that are similar to those produced by psittacofulvins. However, the differential contribution of these pigments to psittaciform phenotypic diversity has not been investigated. Given the color redundancy, and physiological limitations associated to pheomelanin synthesis, this study assumed that the latter would be avoided by psittaciform birds. This hypothesis was tested by using Raman spectroscopy to identify pigments in feathers exhibiting colors suspicious of being produced by pheomelanin (i.e., dull red, yellow and grey- and green-brownish) in 26 species from the three main lineages of Psittaciformes. The non-sulphurated melanin form (eumelanin) were detected in black, grey and brown plumage patches, and psittacofulvins in red, yellow and green patches, but no evidence of pheomelanin was found. As natural melanins are assumed to be composed of eumelanin and pheomelanin in varying ratios, these results represent the first report of impairment of mixed melanin-based pigmentation in animals. Given that psittaciforms also avoid the uptake of circulating carotenoid pigments, these birds seem to have evolved a capacity to avoid functional redundancy between pigments, likely by regulating follicular gene expression. The study provides the first vibrational characterization of different psittacofulvin-based colors and thus helps to determine the relative polyene chain length in these pigments, which is related to their antireductant protection activity. informacion[at]ebd.csic.es: Neves et al (2020) Impairment of mixed melanin-based pigmentation in parrots. J Experim Biol. DOI 10.1242/jeb.225912


https://jeb.biologists.org/content/early/2020/05/08/jeb.225912
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Development of European longterm ecosystem research infrastructures

Development of European longterm ecosystem research infrastructures

Distributed environmental research infrastructures are important to support assessments of the effects of global change on landscapes, ecosystems and society. These infrastructures need to provide continuity to address longterm change, yet be flexible enough to respond to rapid societal and technological developments that modify research priorities. This horizon scanning exercise was done to identify and prioritize emerging research questions for the future development of ecosystem and socio-ecological research infrastructures in Europe. Twenty research questions covered topics related to ecosystem structures and processes, the impacts of anthropogenic drivers on ecosystems, ecosystem services and socio-ecological systems, and methods and research infrastructures. Several key priorities for the development of research infrastructures emerged. Addressing complex environmental issues requires the adoption of a whole-system approach, achieved through integration of biotic, abiotic and socio-economic measurements. Interoperability among different research infrastructures needs to be improved by developing standard measurements, harmonizing methods, and establishing capacities and tools for data integration, processing, storage and analysis. Future research infrastructures should support a range of methodological approaches including observation, experiments and modelling. They should also have flexibility to respond to new requirements, for example by adjusting the spatiotemporal design of measurements. When new methods are introduced, compatibility with important longterm data series must be ensured. Finally, indicators, tools, and transdisciplinary approaches to identify, quantify and value ecosystem services across spatial scales and domains need to be advanced. In summary, to address complex scientific issues sophisticated research infrastructures are required that operate in the longterm, and cover large spatial scales as well as multiple dimensions of ecosystems and socioecological systems. The combined network of LTER sites, LTSER platforms and Critical Zones Observatories offers great potential as a distributed infrastructure. LTSER platforms should be developed into pilot areas that will allow researchers, managers and decision makers to make evidence-based choices which centre on finding the balance between sustaining landscapes and the demands placed upon them by different stakeholders. informacion[at]ebd.csic.es: Musche et al (2019) Research questions to facilitate the future development of European longterm ecosystem research infrastructures: A horizon scanning exercise. J Environ Management DOI 10.1016/j.jenvman.2019.109479


https://www.sciencedirect.com/science/article/pii/S0301479719311971