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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] Neves et al (2020) Impairment of mixed melanin-based pigmentation in parrots. J Experim Biol. DOI 10.1242/jeb.225912
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Complexity of translation of research outputs to society

Complexity of translation of research outputs to society

Researchers in multiple, related fields that address complex social and environmental challenges, have shown ongoing enthusiasm for applying transdisciplinary social-ecological systems research to promote sustainability. However, few studies have evaluated the effectiveness of social-ecological systems approach, assessed its achievements, and identified challenges to its implementation toward knowledge production for environmental conservation. Here, the results of a qualitative, participatory evaluation of several social-ecological systems projects across Europe are reported, using an evaluation methodology tailored to transdisciplinary projects. Sixty-six stakeholder interviews were conducted at four designated Long-Term Socio-ecological Research (LTSER) platforms – Danube Delta and Braila Island (Romania); Cairngorms (Scotland); and Doñana (Spain). Using qualitative analysis, data from interviews were synthesized and then researchers returned to the sites to present findings to stakeholders in focus group discussions in order to incorporate their feedback into conclusions. Although particular scientists at each platform have taken on entrepreneurial roles to operationalize transdisciplinary science, a business-as-usual attitude tends to dominate institutions, limiting meaningful progress toward transdisciplinary objectives, including: integration of social science research, giving non-researcher stakeholders a more meaningful role in advancing relevant research, and improving knowledge exchange among different stakeholder groups, among other issues. This evaluation reflect modest advancements toward reaching the goals of long-term, place-based, social-ecological systems research. In most cases, the components for creating dynamic "research-implementation spaces" are present: a charismatic leader, high-quality research institutions, relationships with stakeholders, and ongoing monitoring, research, and traditional knowledge on a variety of place-based topics. However, creating links, tools, communication, and coordination among these essential parts so that they constitute effective application of scientific knowledge to address societal challenges in environmental sustainability presents many challenges. In short, while all the components of transdisciplinary social-ecological systems research exist at the sites, there is no overarching strategy to link long-term planning and funding, knowledge integration, and priority-setting with stakeholders to ensure the relevance of research for policy and practice. informacion[at] Holzer et al (2019) Evaluating transdisciplinary science to open research-implementation spaces in European social-ecological systems. Biol Conserv 238 DOI 10.1016/j.biocon.2019.108228