JULIES CPR - cichlid pools were put in the pools with...

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<P>Natural selection plays a huge part in evolution. It keeps environments strong by only allowing the organisms with traits most beneficial to the environment to survive. When testing the diversities of guppy populations David Reznick and John Endler used natural selection as an evolutionary tool. <P>Endler and Reznick’s guppies were of the same species but from different populations. These diverse habitats also consisted of different predators. For example, some pools contained killifish that preyed only on the smaller guppies which reproduced at an older age and grew larger. In the other pool there is the pike-cichlid eating only the larger guppies. These guppies grow slower and reproduce earlier. These results led Endler and Reznick to suggest that natural selection plays a major role in growth and age of maturity. Endler and Reznick transplanted guppies into different pools to observe the guppies’ reaction to different predators and test these ideas. The guppies from the pike-
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Unformatted text preview: cichlid pools were put in the pools with killifish as the predator. Over thirty to sixty generations the transplanted guppies grew 14% proving Endler and Reznicks theory about natural selection resulting from the habitat in where organisms live. &lt;P&gt;Endler and Reznick tested a hypothesis claiming that individuals adapted to changes in the environment. They proved this and that natural selection can occur more rapidly. They performed this experiment by transplanting guppies into pools containing different predators. Several generations show the changing rate of growth and age of maturity. The guppies that were transplanted into the killifish pool from the pike-cichlid pool grew and matured earlier compared to control groups. A conclusion was drawn that the change in predator resulted in a change from the guppies leading to a longer and more productive life. The traits most favored became the dominant traits in the guppy population in the tested pool....
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This note was uploaded on 03/27/2008 for the course BIO 1407 taught by Professor Grise during the Spring '08 term at Texas A&M University, Corpus Christi.

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