A Level Biology Revision "Stabilising Selection and Directional Selection" 

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In this video, we look at stabilising selection and directional selection. First we explore stabilising selection, using the example of birth weight in humans. We then look at directional selection, including the presence of antibiotic resistance.
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Basketball
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Staph A
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Content Providers(s): CDC/ Matthew J. Arduino, DRPH Photo Credit: Janice Haney Carr, Public domain, via Wikimedia Commons