Generally animal tissue, made up mostly of protein, degrades quickly. Over the course of millions of years all that is likely to be found from an animal is skeletal remains or an impression of the shape of the animal in surrounding rock. Scientists can learn much about an animal by its bones and impressions, but without organic matter they are left with many unanswered questions.
But melanin is an exception. Though organic, it is highly resilient to degradation over the course of vast amounts of time.
"Out of all of the organic pigments in living systems, melanin has the highest odds of being found in the fossil record," Simon said. "That attribute also makes it a challenge to study. We had to use innovative methods from chemistry, biology and physics to isolate the melanin from the inorganic material."
The researchers cross-checked their work using separate complementary experiments designed to capitalize on various molecular features unique to melanin and determined the morphology and chemical composition of the material. This combination of in-depth, multidisciplinary techniques is not normally used by paleontologists to study fossil samples.
"I think the strength of this paper is that it is not tied to a single method," Simon said. "Any one technique would have brought some insights, but potentially more questions than insights. It was really the more holistic approach that fully characterized it and allowed us to actually do a real comparison between what existed during the Jurassic period and what exists now.
"It's also given us a handle on ways of identifying organic components in fossils that might
|Contact: Fariss Samarrai|
University of Virginia