Echolocation Most bats have echolocation, but some have are more Its rods and cones face forwards, and blood supply and nerves come from behind. Keep up the good work. Megabats on the other hand have bigger eyes. Bat Eyes Vs. Human Eyes Differences between bat species. The retina is inverted and the photoreceptors face the sclera. In the example, 4 denotes the vertebrate blind spot, which is notably absent in the octopus eye. I had no idea it was so complex and similar to a human eye even though after they branched from a distant common ancestor humans and octopuses developed their eyes at different times. Then, tens of millions of years later on the branch leading to cephalopods, it had to "create a camera eye" that is a wonder of nature in squids and octopus. The common octopus was found to have this amino acid in the rhodopsin scientist have long studied the eye sight of Cephalopods and this amino acid is a common amino acid between human and cephalopods vision Cephalopods use this as a neurotransmitter directly to the photo luminescent skin and humans use it in high order brain functions. They have no blind spot! This false eye spot is dark red brown and it is found halfway between the eyes and the base of the arms. Image: Roy Caldwell, Klaus Stiefel, Alexander Stubbs Size Bat's eye size depends on what species it is. Simply put, the eyes of any creature are adapted for their best useage. Figure 1 Schematic outline of the basic tissular elements of vertebrate and invertebrate bicameral eyes. The main difference with the common octopus is a dark spot located beneath each eye of the Mexican four-eyed octopus which is called an ocellus. The octopus eye, it seems, evolved independently to ours and whilst it is similar in many ways the octopus got the retina in ‘the right way’. In both images, 1 denotes the retina and 2 the nerve fibers, including the optic nerve ( 3 ). (A) The eye of vertebrates. The octopus and human eye really shocked me I had never seen an octopus eye before. Q: How do evolutionists explain why the human eye and the eye of an octopus being nearly the same in its complexity? Like wings, eyes have evolved multiple times in different lineages of animals. Distribution of rods and cones along a line passing through the fovea and the blind spot of a human eye  From top, a cuttlefish, squid, and octopus eye, whose weird shapes may allow cephalopods to distinguish color despite being technically colorblind. The ocellus is a spot that looks like an eye. Diseases that Affect the Retina • Macular degeneration – Fovea and small surrounding area are destroyed Human eye Octopus eye Octopus, squid and terrestrial gastropods (slugs and snails) have photoreceptors in the ‘correct’ side of the retina. Microbats, the most common of bats, have small eyes. Transmission of the impulse with here cells (as in mammals), photoreceptor and ganglion, and transmission of the impulse with t two cells (as in fishes); (B) the bicameral eye of the octopus. How could this have happened exactly twice in two speicies that never started as the same organism? But then — without any possible cross-communication — another Pax6 gene on a completely separate branch leading to vertebrates had to learn to create a camera eye all over again. It is apparent that the eye has evolved relatively independently several times among the large group we call animals.