Discovered the oldest footprints of vision in vertebrates
Paleontologists first found fossils of rods and cones - the light-sensitive cells of the retina. These cells belonged to the fish Acanthodes bridgeyi that lived in the seas of the Earth at the end of the Carboniferous period (300 million years ago).
Scientists hope that this vertebrate animal would possess color vision. The results of the study presented in the journal Nature.
Knowledge of scientific workers about the evolution of vision in vertebrates is extremely sketchy in the fossil record preserved calcified cornea (outer lens) compound eyes of arthropods, but pliable tissue of the eye and brain usually disintegrate immediately after death.
Gengo Tanaka (Gengo Tanaka) and his colleague studied the fossil remains of fish Acanthodes bridgei found in geological formations Hamilton (Kansas). This animal is considered to be the last common ancestor of modern clustertech. Probably lived fish in shallow, brackish water. In fossils scientists have noticed the prints of eye tissues and eumelanin.
In tissues notable perfectly preserved rods and cones - these cells also prints eumelanin claim that the photosensitive vision (day use cones, and twilight is more delicate sticks) was 300 million years ago. Sticks and indicate that fish were seen in color, but of course this fact will be able to approve only traces of opsins (proteins photosensitive receptors).
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