The Positive Effects Of Natural Selection: The Origin Of Species

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Natural selection today is considered one of the main processes of evolution, and also thought to be one of the reasons that there is such great diversity between all of the organisms on the earth today (6). The Origin of Species written by Charles Darwin helps explain that for natural selection to occur there must be optimal conditions satisfied; the units must vary, the units must be able to be passed on from generation to generation, and also there must be competition for resources (6). Since all organisms differ and have different traits and genes some organisms will have an advantage over the others and also tend to produce more offspring (6). Lewontin believed that natural selection could be applied to genes, organisms, populations, …show more content…

Due to Mendelian genetics individual selection is greatly accepted by many biologists. Darwin placed individual organism at the ‘center of the biological universe’ (6). Individual organisms are the ones who will have an advantageous trait that will be passed on to their offspring, which will in turn result in the change of populations and even species over time (6). Traits themselves are selected upon due to the fact that they will either have a positive effect or a negative effect on an individual. The positive effects will help the individual survive and in turn help them produce more offspring and pass on their genetic information (6). Individuals act on their own needs and will display selfish behaviors. Natural selection favors these selfish genes due to the fact that there is no risk in receiving the benefit …show more content…

Group selection is whenever a group of individuals benefits from the survival and reproduction of the group as a whole (1). These individuals are not related so this is not kin selection. This level of selection is not widely supported due to the fact that many characteristics that benefit the group also benefit the individual. An example of this would be whenever food is scarce an population would as a whole favor reproductive constrain, but natural selection does not favor this natural selection favors individuals that produce more offspring. This means that whenever an individual mutates and produces more offspring they will become favored by natural selection. Even though there were no selfish genes in this population, selfish genes mutate and then will be spread throughout this population (1). Groups have much slower life cycles than individuals so natural selection does not work as strongly (1). Wades did an experimental study on flour beetles and tested individual and group selection in a lab. He found that natural selection occurred on both levels, but this does not show the kind of adaptations that would of occurred in nature

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