FAQ: Is the difference between eumelanin and phaeomelanin visible on cross sections of feathers?
Yes, that difference is clearly visible provided the cross-sections are made in the right way, with professional material and with the right chemicals. Then you can see clear colour differences between eumelanin and pheomelanin (by the way, the shape of both pigments is also different).
In recent years, however, we have not used many cross sections any more because we can also demonstrate the presence of eumelanin and pheomelanin with other, more high-tech techniques. With these techniques it is even possible to compare the amount of concentration of the pigments present with, among other things, the wild type and thus determine precisely whether more or fewer pigments are present. This is not always possible with cross-sections, so we prefer the new and unfortunately more expensive techniques 🙂