Palaeocolour reconstruction in fossil amniotes
Photo by Amber Flowers on Unsplash
What is it about?
Colour and patterns are critical to understanding the life, ecology and behaviour of animals. Animals routinely use colour patterns while looking for potential mates, as warning signals to defend their territories and camouflage for hunting or for escaping. Different colours in vertebrates range from blacks, greys and reds to yellows and greens produced by pigments like melanin, carotenoids, pterins, flavins, psittacofulvins, and porphyrins. These are found all across the vertebrate evolutionary tree.
Why is it important?
In the last ten years, melanin-based colour patterns have been reconstructed in over 30 fossil animals including birds, non-avialan dinosaurs and mammals. Unfortunately, our knowledge of other pigments is scarce in the fossil record as these non-melanin pigments are more difficult to fossilise. This incomplete knowledge and the lack of a standard study approach have been prevailing challenges to the reconstruction of colour in fossil animals.In our new paper, Dr. Michael Pittman and I at the Vertebrate Palaeontology Laboratory, University of Hong Kong with our international collaborators, propose a framework that overcomes past challenges by incorporating the chemical signatures of different pigments, large and small-scale anatomical details visible in fossils as well as the potential for non-melanic pigments to fossilise. This comprises four main steps: (1) Map the known or suspected extent of preserved colour and patterns in the specimen; (2) Search for pigment-bearing microstructures using electron microscopy e.g. microstructure shape can be used to identify melanin-based colours like black, grey, brown and iridescence and non-iridescent blue; (3) If melanin-based colours are not detected, use high-end chemical analysis techniques to detect biomarkers of other pigments (4) Use reconstructed colours and patterns to test fundamental hypotheses related to animal physiology, ecology and behaviour.
The following have contributed to this page: Arindam Roy and Dr. Evan Thomas Saitta
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