CA Evolution Part 1 - these chemicals. Once pesticide...

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Evolutionary Mechanisms Decide which evolutionary mechanism is involved. Explain your answer. 1. All of the cattle on Iceland are descended from a small group of cattle brought to the island more than 1000 years ago from Norway. The genetic makeup of the Icelandic cattle is now significantly different from the Norwegian cattle. 2. Prior to the extensive use of pesticides that began in the 1940s, insects that feed on crops only contained a small amount of genetic variability for resistance to
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Unformatted text preview: these chemicals. Once pesticide spraying became widespread, the insects that had resistant genes became much more frequent and passed more of their genes on to the next generation. As a result, after sixty years of pesticide applications, these insects are now very resistant to common pesticides and are no longer harmed by these chemicals....
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This note was uploaded on 10/01/2011 for the course BIOL 1407 taught by Professor Lisagloyna during the Spring '09 term at Austin Community College.

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