Characters: Will, Shawnte, Erica
Setting: It’s early morning. Erica and Shawnte are sitting on the steps outside of school. Will walks up to them. Erica looks upset.
Will: What's wrong with Erica?
Shawnte: She's been quiet since I got here. Erica, what’s up?
Erica: My dad ran over some birds by the park.
Shawnte and Will: What?!
Shawnte: That's messed up. What happened?
Erica: There were lots of pigeons on the road and my dad just drove right through them. I thought they’d get out of the way, but it felt like we ran over something. There were feathers under the car when I got out. It made me feel terrible.
Will: Good for your dad. Pigeons are nasty birds. There are too many of them anyway.
Shawnte: It doesn't matter how many there are. It's still wrong to kill them!
Erica: My dad said that if they weren't fast enough to get out of the way, they didn't deserve to survive. He said he was helping the pigeon population by killing the slow and dumb ones. Which I think is kind of sick.
Will: How does killing pigeons help them? I don't get it.
Erica: Well, he said if you kill all the slow and stupid pigeons, only the smart and fast ones survive. You’re helping nature with natural selection.
Shawnte: It doesn’t sound natural; it sounds pretty messed up to me.
Shawnte, Will, and Erica keep talking. Erica pulls up an entry for natural selection on her phone, but it doesn’t make much sense to her. She doubts Shawnte will get it either, but she decides to read it out loud anyway.
Erica: I’m not sure, but I think this is the basic idea. Listen:
Natural selection is the gradual, nonrandom process by which biological traits become either more or less common in a population as a function of differential reproduction of their bearers. It is a key mechanism of evolution.
Shawnte: Oh, that probably just means there’s, like, a type of bird or fish and some are red and some are green. Say the red ones do better for some reason and the green ones bite the dust more often. Of course, you’d get more baby red ones going forward even if the color was just random before.
Erica: (shocked that Shawnte understood) Who ARE you? And what have you done with Shawnte?
Shawnte: (ignoring the insult) Maybe your dad thinks that since he killed the slow pigeons, the ones that are left will have babies that will be smarter or faster.
Will: Maybe after enough time we'll have pigeons with super powers! I saw this TV show a couple of weeks ago about how some pigeons have a GPS in their head. They can sense where they are and find their way home. That's like a super power.
Shawnte: Yeah, right. I’m looking that up. What were those pigeons called?
Will: Homing pigeons, I think.
Shawnte: Hang on...whoa! This says that pigeons can find their way home from a thousand miles away! Some people even have racing pigeons and breed their own pigeons.
Erica: Is pigeon breeding like dog breeding? My friend’s mom breeds dogs. She finds dogs that have traits like soft fur and cute faces and has them make puppies.
Shawnte: Hey, it says here that Charles Darwin did sort of the same thing as your friend's mom. But he bred pigeons, not dogs.
Will: We learned about Darwin earlier. He was that evolution guy. So breeding is a kind of evolution?
Shawnte: That makes sense! By mating certain dogs together, you can get puppies with the traits you want. The dog population changes over the generations.
Erica: But I thought evolution was all about survival of the strongest. My friend's mom breeds dogs to be cute and fuzzy. Those dogs are pretty weak.
Will: Evolution is just living things changing over time. It doesn't say that they have to get stronger or faster. If that was true, everything would be super buff.
Shawnte: (pointing to phone) It says here that breeding animals is a kind of evolution called artificial selection. People select what survives and reproduces.
Erica: But humans don't go around breeding everything. How does evolution happen in nature?
Will: I guess things like weather and predators select who survives and reproduces. If you have traits that don’t help you succeed in your environment, you don't stick around to make babies.
Erica: But isn't that survival of the strongest?
Will: No. You don't have to be strong to survive.
Shawnte: Yeah, you could be hard to see, or have a good sense of smell, or have protective poison or something. This website says that most plants and animals evolve through natural selection. Natural selection is when some groups of plants or animals are better adapted to their environment than others and so they survive and reproduce. Being a good fit for your environment is called “fitness.”
Erica: Wait, I thought fitness meant being in good shape, like you’ve worked out a lot?
Shawnte: Fitness does mean that in P.E. class, but the meaning is a little different in science.
Will: Okay, so when your dad ran over pigeons with his car, was it artificial selection or natural selection?
Erica: Well, we didn’t breed them, we just ran over the slow ones according to my dad. So it must be natural selection.
Shawnte: Yeah, but because your dad ran them over, humans did it. It must be artificial selection.
Erica: Either way, I still say it’s messed up. I wish my dad taught me about evolution some other way.