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Open Call for Research Projects in ICTS-Doñana!

The Singular Scientific and Technical Infrastructure Doñana Biological Reserve (ICTS-Doñana) announces the opening of a call for international research projects in the Doñana Natural Space.

Las altas temperaturas están provocando que las lagunas y las marismas de Doñana pierdan agua rápidamente

La superficie inundada en la marisma es de un 78% pero la profundidad es escasa. Por otra parte, sólo el 1,9% de las lagunas temporales están inundadas. Las precipitaciones crean una oportunidad...

Traffic noise causes lifelong harm to baby birds

A study with CSIC participation reveals for the first time that car noise harms individuals throughout their lifetime even years after exposure

Illegal wildlife trade, a serious problem for biodiversity and human health

A research team led by the Doñana BIological Station and the University Pablo de Olavide have detected wild-caught pets in 95% of the localities in the Neotropic and warns of the risk of zoonotic...

Urbanization and loss of woody vegetation are changing key traits of arthropod communities

Urbanization is favouring smaller beetle species and larger spider species with greater dispersal capacity.

The loss of woody areas is linked to a decline in the duration of the activity...

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Identification and quantification of melanin types by Raman spectroscopy

Identification and quantification of melanin types by Raman spectroscopy

Melanins are the most prevalent pigments in animals and are involved in visual communication by producing colored traits that often evolve as intraspecific signals of quality. Identifying and quantifying melanins are therefore essential to understand the function and evolution of melanin-based signals. However, the analysis of melanins is difficult due to their insolubility and the lack of simple methods that allow the identification of their chemical forms. We recently proposed the use of Raman spectroscopy as a simple, noninvasive technique that can be used to identify and quantify melanins in feathers and hairs. Contrarily, other authors later stated that melanins are characterized by a lack of defined Raman signals. Here, we use confocal Raman microscopy to confirm previous analyses showing that the two main chemical forms of melanins (eumelanin and pheomelanin) exhibit distinct Raman signal and compare different excitation wavelengths to analyze synthetic pheomelanin and natural melanins in feathers of different species of birds. Our analyses indicate that only laser excitation wavelengths below 1064 nm are useful for the analysis of melanins by Raman spectroscopy, and only 780-nm laser in the case of melanins in feathers. These findings show that the capacity of Raman spectroscopy to distinguish different chemical forms of melanins depends on laser power and integration time. As a consequence, Raman spectroscopy should be applied after preliminar analyses using a range of these parameters, especially in fragile biological tissues such as feathers. informacion[at]ebd.csic.es Galván & Jorge (2015) Dispersive Raman spectroscopy allows the identification and quantification of melanin types Ecol Evol DOI: 10.1002/ece3.1453