ShmoopTube

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Here’s your Shmoop du jour, brought to you by traveling animals.

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It’s why those snakes had to get on the plane…. [Samuel L Jackson with a lot of snakes boarding a plane]

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Seriously, what was Samuel L. Jackson’s problem…?

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They just wanted a nice vacation….

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All right, here we go:

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For what purpose do animals travel in packs, schools, or swarms?

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And here are the potential answers:

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(A) To decrease gene flow (B) To increase the fitness of the individual

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and the survival of the population (C) To increase genetic drift

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(D) To decrease competition between species

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First let's take a look at what happens when animals do hang out together. [Animals hanging out by a pool of water]

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Well, animals that cooperate with each other are often more successful.

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Take wolves, for example... [Two wolves walking in a forest together]

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These two guys hang out together, they eat together, they play Xbox together…

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Okay, fine, one of those things isn’t true. [Wolves playing Xbox together]

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...They usually eat separately.

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Anyway.

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They’re part of a pack.

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And being part of a pack can get you your next meal, or unlock some cool achievements [Wolves in a pack wearing wolf pack t-shirts]

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when you play Call of Duty together.

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And you don’t even have to be part of a blood thirsty, Xbox playing pack.

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You could prefer hanging out with a school of fish and still end up with some sweet benefits. [A fish swimming with other fishes]

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Y’know like...not being eaten.

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So hanging out in groups can either help you find more food or avoid being food. [A pack of wolves with a plate of food]

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Sounds like a pretty good way to increase your chances of survival.

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Now let’s go back to the possible answers, starting with (A), to decrease gene flow.

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Gene flow is the transfer of genes from one population to another.

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It’s basically what happens when two groups randomly bump into each other and make more [Two birds bump into each other]

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babies.

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Which is also why we were terrified of bumping into anyone for a solid ten years of our life...and

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may still have our protective plastic bubble in the garage... [Man rolling around in a plastic bubble]

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So if you hang out in groups, you have a better chance of increasing gene flow, so the answer

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can’t be A.

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Now for answer B.

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We already established that hanging out in groups increases survival, both in real life

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and in Call of Duty.

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And increased survival means that everyone in that group is ‘fitter’. [Wolves hanging out together]

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Except for that one guy who swears by an exercise regime of lifting the remote control once

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every two hours. [A wolf using the television remote]

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So it looks like B is the correct answer.

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But just for fun, let’s take a quick look at answers C & D.

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C is all about increasing genetic drift.

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We know that genetic drift is the change in frequency of a trait in a population.

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Like trying to keep track of how many black sheep are in a flock over 10 years. [Man counting black sheep in a flock]

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If only we didn’t keep falling asleep while we were counting them…

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But we also know that that’s not what we’re looking for, so we can toss it out.

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And we know we can eliminate D, “to decrease competition between species.”

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Hanging out in groups has nothing to do with that. [Wolves in a pack eating together]

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Seriously, ask our Call of Duty buddies.

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No decrease in competition, there...

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It all depends on which species are interacting, how large the groups are and so on…

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And we can’t forget about resources and population densities and yadayadayayada...so

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we can toss out D.

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B is definitely our guy.

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Now back to counting those sheep. [Man attempts to count black sheep]

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This time we’re really going to do it, we’re...we’re….zzzzzzz

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(snore)

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