ShmoopTube

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Here’s your Shmoop du jour, brought to you by small populations.

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If that describes your Twitter following, you may want to consider tweeting about more [James Smith's twitter following page]

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exciting topics.

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And no, corn is not exciting.

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All right, let's take a look at the question…

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A small population of organisms is prone to...what?

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And here are the potential answers

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Let's start at the very beginning. [Caveman starting a fire]

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We hear it's a very good place to start.

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Mutation is a natural process that changes a DNA sequence and the precise order of nucleotides

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within a DNA molecule.

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It's also the reason why it's safe to say that no two people are alike. [Two guys take off their hats]

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So all this time you've called your little brother a mutant?

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You're not too far off base. [Family sitting down for dinner]

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Random genetic changes have little or no effect on a small population of organisms making

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“A” incorrect.

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Moving on to “B,” nonrandom mating. [A couple kissing]

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Nonrandom mating occurs within organisms when there are plenty of potential mates to choose

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from.

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It's provides the opportunity within a large gene pool to pick out a mate based on compatibility, [A large swimming pool]

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or desirable traits.

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In a small population, there’s no chance to pick and choose.

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All you can do is hope your mate likes death metal, because it’s all random selection. [Man picking a mate]

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All of this means that “B” is the wrong answer.

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How about D, high migration rates?

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Well, there's nothing that indicates that a small population has any more desire to

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pick up and move than a larger population would. [Baby deer prancing in a field]

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That's not to say it wouldn't happen given the right circumstance.

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Sometimes you end up with high rent, or irritating neighbors.

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So while a small population may be prone to migration, it is not prone to high migration

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rates, which means answer “D” is incorrect.

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Which leaves us with “C”.

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Genetic drift is the change in the frequency of a gene variant. [Graph depicting change in frequency of a gene variant]

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The smaller the population, the more susceptible it is to dramatic changes in gene frequencies.

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In other words, genetic drift can determine whether an individual within a small population

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reproduces or even survives.

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Genetic drift can have a large impact on a very small population, meaning that C is the

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correct answer.

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And seriously.

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Stop tweeting about corn. [Man tweeting about corn on his mobile]

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No one should care this much about corn. Seriously, come on people.

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