Phobos
Jul22-03, 01:30 PM
food for thought...
http://www.boston.com/dailyglobe2/203/science/Eyes_key_to_theory_for_early_explosion_of_life+.sh tml
Parker's explanation for this explosion is simple: It was caused by the development of the eye, an organ that not only senses light, but can see an image. He states that the trilobite evolved its eye about 543 million years ago, which would have been in time to help ignite the Cambrian explosion. Once eyes developed, there would have been a revolution in predation. According to Parker, the period before the Cambrian ''was rather an experimental stage for predation, occupied mainly by peace-loving vegetarians that were willing enough to accept any occasional animal matter they stumbled upon.'' But once the ''light switch'' was turned on, the randomness of the hunt was gone. Since every animal could be seen -- predators included -- the rules of survival changed. ''So to adapt to vision,'' Parker writes, ''an animal must evolve a response in terms of adapting its visual appearance, whether it is warning shapes and colours, camouflage or hiding behind physical barriers.''
http://www.boston.com/dailyglobe2/203/science/Eyes_key_to_theory_for_early_explosion_of_life+.sh tml
Parker's explanation for this explosion is simple: It was caused by the development of the eye, an organ that not only senses light, but can see an image. He states that the trilobite evolved its eye about 543 million years ago, which would have been in time to help ignite the Cambrian explosion. Once eyes developed, there would have been a revolution in predation. According to Parker, the period before the Cambrian ''was rather an experimental stage for predation, occupied mainly by peace-loving vegetarians that were willing enough to accept any occasional animal matter they stumbled upon.'' But once the ''light switch'' was turned on, the randomness of the hunt was gone. Since every animal could be seen -- predators included -- the rules of survival changed. ''So to adapt to vision,'' Parker writes, ''an animal must evolve a response in terms of adapting its visual appearance, whether it is warning shapes and colours, camouflage or hiding behind physical barriers.''