The evolution of the eyes has attracted significant study with the study with the eye distinctively it is difficult to estimate the rate eye evolution becausethe fossil record particularly of the early
Eyes<span> are critical because, for the 'vast majority of animals', vision is </span>their<span> 'most ... Natural selection</span>should<span>, under many circumstances, favor the increments. ... The oldest </span>eye<span> in the </span>fossil record<span>, that of a trilobite, is a </span>very<span> complex faceted ... </span>eye<span>, and in particular the lens, has changed </span>very little<span> during the course of </span>evolution<span>.</span>
