NARRATOR：

Listen to part of a conversation between a student and her biology professor.

MALE PROFESSOR：

So the assignment is to reproduce one of the animal camouflage experiments we read about in our text book.

Which experiment did you pick?

FEMALE STUDENT：

Well... I was wondering if I could try to reproduce an experiment that’s...kinda the opposite of what was discussed in the textbook?

MALE PROFESSOR：

So, instead of how and why an animal might hide itself, you want to do something about why an animal might want to be seen? Hmmm. Tell me more.

FEMALE STUDENT：

Well, I got the idea from one of the journals you said we should look at…

it’s an experiment about, um, [upspeak] they called them eyespots in the article?

<-MALE PROFESSOR:->Eyespots, sure. The patterns on the wings of moths and butterflies that are generally believed to scare off predators because they look like big eyes?

FEMALE STUDENT：

Yeah. Except the article was about an experiment that disputes that theory.

MALE PROFESSOR：

Well, we know that the markings do scare the birds, but the idea that the spots look like eyes is, well that’s just a commonly held belief.

FEMALE STUDENT：

So...that’s not even based on research?

MALE PROFESSOR：

Well, this whole idea of moth or butterfly markings being scary because they look like eyes rests on how we imagine that their predators, like birds, perceive the markings.

And we can never really know that. All we can do is observe bird behavior. But tell me more about the experiment.

FEMALE STUDENT：

OK, so the experiment looked at the shapes of the markings on moth wings.

The researchers wanted to know if the markings that were round or eye-shaped were more effective at deterring predators than square or rectangular markings.

MALE PROFESSOR：

OK…

FEMALE STUDENT：

Yeah. So, they attached food to paper models of moths, with different shaped marks drawn on the wings, to see how birds reacted.

And what’s interesting is they realized that the round marks were not more effective at scaring birds than other shapes.

MALE PROFESSOR：

Were they less effective?

<-FEMALE STUDENT:->No, they were about the same. But what researchers did determine is that larger markings are more effective than smaller markings at scaring off prey.

They called this phenomenon “visual aliveness.”

MALE PROFESSOR：

Visual aliveness. huh. Well, I guess it’s not all that shocking, if you think about it.

FEMALE STUDENT：

So, anyway, is it OK? Can I repeat this experiment and write about it?

MALE PROFESSOR：

Yes, I think that’ll work. The problem I foresee is, well, where?

This is an urban campus...You’ll have a hard time finding a good place to set up the experiment.

FEMALE STUDENT：

Oh, I-I wasn’t planning on doing it on campus.

I’m going home for spring break, and my family lives in the country, far from the nearest city. I can set it up in the backyard.

MALE PROFESSOR：

Good idea. Except one week is not a lot of time. So you’ll need to make some adjustments to have enough data.

I’d set up the experiment near a bird feeder, and get in as much observation time as you can.