Fossil remains suggest color vision in ancient fish species
DOI: 10.1063/PT.5.028523
Los Angeles Times : The fossil of a fish has been found that was so well buried in sediment that even soft tissue from the eyes was preserved. Uncovered in the Hamilton Quarry in Kansas, the fish—a member of the species Acanthodes bridgei—was about 10 cm in length and lived about 300 million years ago. At that time, the quarry would have been a shallow lagoon. Fossils found there have been well preserved not only because they were buried quickly in sediment but also because prior to burial, bacterial activity resulted in the fish’s eyes being covered by a thin film of phosphate. According to the paper published in Nature Communications, researchers say this is the first ever study of mineralized rods and cones in a fossil eye and their results suggest the fish likely had color vision.