As I mentioned in the natural selection expected learning outcomes, I want you to understand the three patters on selection- directional selection, stabilizing selection, and disruptive selection. In addition, to the readings in your textbook, you will find useful info on this topic in the Encyclopedia of the Earth article on Evolution http://www.eoearth.org/article/Evolution.
Expected Learning Outcomes
By the end of this course, the fully engaged student should be able to
- distinguish between directional, stabilizing, and disruptive selection
- describes how directional. stabilizing, and disruptive selection work
- give examples of traits produced by each of these patterns of selection
- draw the graph that shows the relationship between fitness and trait size that produces each of these patterns of selection.
In answering the question "how is the organism's phenotype subject to natural selection?" - Does natural selection work on altering the frequency distribution of heritable traits PRIMARILY in these three ways or ONLY in these three ways?
ReplyDeleteThese three patterns are the main possible results of selection because they focus on the three broadest possible relationships between phenotype and fitness. A different relationship between phenotype and fitness could produce a different pattern of selection.
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