Dan - Eric Nilsson ( Evolution of the Eye) An Evolutionary Biologist

Dan-Erik Nilsson : A Research

2007

Dan-Erik Nilsson : A Research

How truly complex and remarkable structures such as the human eye could evolve has almost always been one of the direst questions that have puzzled biologists around the world . We know that human sight relies on the ability of our eye to be able to form a clear and focused image on the retina . There are many researchers who have studied this issue , most of which who have suggested that prior to the evolution of the lens there was a regulatory link

between two tiers of genres , those that would later become responsible for controlling lens development , and those that would help give the lens its special physical properties .it is .This combination of genes which appears to have then been selected in an early vertebrae during the evolution of its visual system , giving rise to the lens (Current Biology , 2005 . The history of research on this matter is long and extensive , and although there are really no evolutionary biologists known better than Charles Darwin , who stated that To suppose that the eye , with all its inimitable contrivances for adjusting the focus to different distances , for admitting different amounts of light , and for the correction of spherical and chromatic aberration , could have been formed by natural selection , seems , I freely confess , absurd in the highest possible degree (Ridley , 2004 . There are also many other evolutionary biologists who must be taken into consideration here , one in particular to be referenced in this report Dan-Erik Nilsson

When it comes to a subject such as evolutionary biology , there are plenty of critics and skeptics that are present in this regards . Through natural selection , there have been many very different types of eyes which have emerged in evolutionary history in general , and for instance Darwin , who was one of the first truly recognized , acknowledged from the start that the eye would have been a difficult case for his new theory to explain . Difficult , but not impossible . Scientists have come up with scenarios through which the first eye-like structure , a light-sensitive pigmented spot on the skin , could have gone through changes and complexities to form the human eye , with its many parts and astounding abilities (Evolution Library , 2007 . Biologists in general use the range of less complex light sensitive structures that exist in living species today in to come to hypotheses regarding the various evolutionary stages that eyes may have gone through over time

One evolutionary biologist in general who has sparked much controversy especially regarding the issue of the evolution of the eye , is Dan-Erik Nilsson . I chose this individual to focus on for this assignment because he has been so renowned and recognized in terms of his contributions to this matter . Specifically , his major contribution to evolution was his demonstration that a primitive optical sense organ could evolve into a complex human-like eye within a reasonable period (less than a million years ) simply through small mutations and natural selection (Nilsson 1994...