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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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Evaluation of the network of protection areas for the feeding of scavengers in Spain

Evaluation of the network of protection areas for the feeding of scavengers in Spain

Protected areas are one of the most common strategies for wildlife conservation worldwide. However, their effectiveness is rarely evaluated. In Europe, after the outbreak of bovine spongiform encephalopathy, a restrictive sanitary regulation prohibited the abandonment of dead livestock in extensive farming in the field, which led to negative consequences for scavengers. As an attempt to mitigate this negative impact, a new regulation was approved to allow farmers to leave extensive livestock carcasses in the so-called "Protection areas for the feeding of necrophagous species of European interest" (PAFs). General aims of this study were to quantify (i) the proportion of breeding distribution of targeted scavenger species overlapping PAFs; (ii) the extensive livestock carrion biomass available inside PAFs; (iii) the proportion of breeding distribution of non-targeted scavenger species falling within PAFs; (iv) the overlap between the home range of vultures and PAFs, as well as the extent to which vultures move through different administrative units; and (v) the savings in greenhouse gas emissions in relation to the pre-PAF scenario. Results show that the implementation of the new sanitary regulation by means of areas for the feeding of scavengers could mean an important improvement in scavenger conservation and a noteworthy reduction of greenhouse gas emissions. However, some gaps related to the distribution of endangered facultative scavengers were identified. Moreover, given that vultures are highly mobile organisms, the design and management of these feeding areas should be coordinated at both the supra-regional and supra-national scales. informacion[at]ebd.csic.es: Morales-Reyes et al (2016) Evaluation of the network of protection areas for the feeding of scavengers in Spain: from biodiversity conservation to greenhouse gas emission savings. J Appl Ecol doi:10.1111/1365-2664.12833


http://onlinelibrary.wiley.com/doi/10.1111/1365-2664.12833/abstract