�y��vlog

In work published in 2016, he and his colleagues looked carefully at the different trace metals in pigments from modern feathers and found that whereas eumelanin contains copper, pheomelanin contains sulfur and zinc.

But its sister pigment called pheomelanin, which gives skin and hair a pink or red hue, has been tougher to nail down.

Now that scientists know what to look for, Wogelius says, he’s confident the pheomelanin signature will be detectable in much older fossils.

The new data support the team’s previous claim of evidence for pheomelanin in a 30-million-year-old fossil tadpole.

In the yellow hairs, the researchers noticed the melanin had changed to a sulfur-containing type called pheomelanin, seen in animals with yellow, red, or orange tones.