Rod and Cone cells that are in our eye and help us in our vision have been found in an eye of an ancient fossil dating back to over 300 million years.
This finding indicates that these cells evolved at least that much time ago and the ancient fish probably saw in color. These are the oldest photoreceptors ever found in a vertebrate eye.
Rod cells are long thread like and are more sensitive to light enabling us to see and also number in about 120 million whereas the triangular cone cells number only 6 to 7 million but are responsible for giving color to our vision.
The 4 inch well preserved fossil was unearthed in Kansas and now is the property of the National Museum of Nature and Science in Tokyo. The fossil is of a fish known as Acanthodes Bridgei.
Since Rods and Cones are composed of a fragile soft tissue, they usually start to disintegrate within days following the animal’s death. But this fossil was probably very quickly covered in sediment.
The fish is quite similar to a modern day fish called the Rhinogobius which is a small Gobi fish often kept in aquariums. The ratio of rod and cone cells was also about the same in both the fish as well.
This finding illustrates that the development of eyes can be traced back to hundreds of millions years ago and we can also say that dinosaurs were able to see in color as well.