Mutations In a Population

Mutations In a Population

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  CHAPTER 3: MUTATIONAND ADAPTIVE TRAITS 3.2: Mutations in a Population
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  3.2.1: WARM-UP Remember, theSim from last lesson’s homework is a model of natural selection. Scientists sometimes use models to investigate changes to a population that they couldn’t actually make in real life. For example, up until this point when we’ve used the Sim, the Mutation toggle was always off. This meant mutations could not occur. You can’t actually turn off mutations in real populations because mutations happen randomly. Another way the Sim is different from the natural world is in its frequency of mutations. In the Sim, mutations happen pretty frequently so that you can learn how they impact populations. However, they happen much less often in real life.
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  3.2.1: WARM-UP
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  3.2.2: REREADING MUTATIONS Inthe last lesson, we read that new traits can become part of a population when mutations happen. Today, we are going to think about how these traits could become more common in a population over generations. You will reread the article you chose from Mutations to answer the new Investigation Question. As you read, focus on the trait that was introduced by a mutation and think about whether it became more or less common in the population over generations.
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  3.2.2: REREADING MUTATIONS Studentsread. Work with a partner who read the same article to answer these questions.
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  3.2.3: INVESTIGATING MUTANTFUR TRAITS IN THE SIM Students will investigate in the Sim whether traits created through mutation are always adaptive. (15 min) You will use the Sim to investigate an ostrilope population that only has a trait for low fur (Level 2) in a cold environment. You will see what happens when mutations are allowed to introduce new fur traits into the population. QUESTION: Will non-adaptive, low-fur traits be introduced through mutations? ANSWER HERE
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  3.2.3: INVESTIGATING MUTANTFUR TRAITS IN THE SIM You will be able to investigate in the Sim whether mutations can introduce non-adaptive traits into populations. Review the steps to complete the Sim activity and emphasize the fur-trait histograms.
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  3.2.3: INVESTIGATING MUTANTFUR TRAITS IN THE SIM Launch the Sim and load the Mutations and Traits mode.
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  3.2.3: INVESTIGATING MUTANTFUR TRAITS IN THE SIM Change the temperature of the environment to cold (Level 1) by moving the Temperature slider.
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  3.2.3: INVESTIGATING MUTANTFUR TRAITS IN THE SIM Turn ostrilope fur-trait mutations on by pressing the Ostrilope icon and pressing the Mutations toggle. •Press RUN and observe the population for at least 50 generations.
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  3.2.3: INVESTIGATING MUTANTFUR TRAITS IN THE SIM •Press ANALYZE and use the Generations slider to carefully observe new traits in the population.
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  3.2.3: INVESTIGATING MUTANTFUR TRAITS IN THE SIM Answer the Following based on the SIM
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  3.2.4: REFLECTION Work independentlyto complete the reflection. KEEP THIS CONCEPT IN MIND! •ALSO: •Mutations happen randomly; individuals can’t choose to have a mutant trait. •Mutations can create traits that can be adaptive, non-adaptive, or neutral depending on the environment. •If the mutant trait is adaptive it will become more common, if it is non-adaptive it will become less common. ANSWER THESE
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  3.2.5 READING ANDRESPONDING TO SHERMAN •Read the story and answer the questions.