Octopus Eye

Octopuses have a very acute vision with complicated eyes that developed independently of mammalian eyes. The eye consists of an iris, a lens, a vitreous cavity, pigment cells and photoreceptor cells that with help of photosensitive

pigment change energy of light into electric nerve signals. The octopuses´ eye is formed as an protrusion of the body surface and, consequently, incoming light hits firstly the right part of photoreceptive cells, unlike in vertebrates´ eye, where it has to firstly pass through nerves and cell bodies. The eye is focused by the movement of a spherical lens rather than changing its shape. The pupil is autonomously kept horizontal all the time.