Evolution of the eye

The evolution of the eye is the origin and development with diversification by natural selection over geological time of organs of photosensitivity and vision in living organisms. Many scientists have found the evolution of the eye attractive to study because the <a href="/facts/Eye/h3lbYU55">eye</a> distinctively exemplifies an <a href="/facts/Convergent_evolution/dd0L8z4R">analogous</a> <a href="/facts/Organ_(anatomy)/FUYsLaxz">organ</a> found in many <a href="/facts/Taxon/caQC1e87">animal forms</a>. Simple light eye evolution is the distinction between different types of photoreceptor cells. Salvini-Plawen and Mayr ( 1977 ) noted a remarkable diversity of photoreceptor cell morphology across the animal kingdom, and suggested that photoreceptors evolved independently numerous times." – Land, M.F. and Nilsson, D.-E., Animal Eyes(2-nd ed.), Oxford University Press, Oxford (2012), p. 7.</ref>
Diverse eyes are known from the <a href="/facts/Burgess_shale/4NX5HqIM">Burgess shale</a> of the <a href="/facts/Middle_Cambrian/5NcBhyEU">Middle Cambrian</a>, and from the slightly older <a href="/facts/Emu_Bay_Shale/V2GJjUcn">Emu Bay Shale</a>.
Eyes vary in their <a href="/facts/Visual_acuity/1hj2u0ej">visual acuity</a>, the range of wavelengths they can detect, their sensitivity in no light, their ability to detect motion or to resolve objects, and whether they can <a href="/facts/Colour_vision/j3ou3Izz">discriminate colours</a>.

Evolution of the eye open-in-new

Evolution of the eye