Scientists may have to rethink their theories on what colours dinosaurs were, following a study at University College Cork (UCC).
Many scientists had assumed that the pigment melanin found in fossils came from the skin, and had based their ideas on the colours of ancient animals accordingly.
However, researchers at the university have discovered new sources of the pigment which they say will force scientists to rethink how they reconstruct the colour of fossil birds, reptiles and dinosaurs.
Dr Maria McNamara, who led the team, said that “it’s absolutely critical that we understand the origins of melanosomes in fossils if we want to produce accurate reconstructions of the colours of ancient animals”.
The team used powerful microscopes and chemical techniques to study internal tissues of modern frogs to show that internal melanosomes are highly abundant in them.
Prof Mike Benton, from the University of Bristol, said: "This means that these internal melanosomes could make up the majority of the melanosomes preserved in some fossils."
The team also used decay experiments and analysed fossils to show that the internal melanosomes can leak into other body parts during the fossilisation process. However, there is a way to tell the difference between melanosomes from internal organs and the skin.
“The size and shape of skin melanosomes is usually distinct from those in internal organs,” said Dr McNamara. “This will allow us to produce more accurate reconstructions of the original colours of ancient vertebrates.”