Opsin And The 600 Million-Year-Old Origins Of Vision
Researchers writihg in Proceedings of the Royal Society B say they have made a discovery in understanding the origins of human vision. They say they have determined which genetic 'gateway,' or ion channel, in the hydra is involved in light sensitivity. Hydra are simple animals that, along with jellyfish, belong to the phylum cnidaria. Cnidarians first emerged 600 million years ago. Complex traits with components of individual evolutionary histories are always more difficult to understand but a gene called opsin is present in vision among vertebrate animals and is responsible for a different way of seeing than that of animals like flies. The vision of insects emerged later than the visual machinery found in hydra and vertebrate animals. read more