•Narrator: Now listen to two students discussing the article.

•Man: So what do you think of the university's new plan?

•Woman: Oh, I don't know,

•I don't think it's gonna work.

•Man: No?

•Woman: I mean I can't imagine top students being too thrilled about some of the conditions on this campus.

•Man: What do you mean?

•Woman: Like the science laboratories having such old, outdated equipment,

•and the library needing more books and the student center being so small.

•I think that the two million could be spent in better places if the university is really serious about achieving its goal.

•Man: OK, but what about the other reason for building the stadium?

•I mean right now we have so little contact with the town.

•Woman: Yeah, but this won't help relations.

•Look, people from town hardly ever come to games because our teams always lose and they are not suddenly going to improve overnight.

•Besides, adding seats won't make a difference.

•I mean if people from town didn't come before, they won't come now just because the place is bigger.

•Narrator: Now listen to part of a lecture on this topic in a Psychology class.

•Professor: Let's take an everyday example -- an ordinary round plate like you'd find in a kitchen.

•If you hold the plate directly in front of your face and look at it,

•what shape do you see?

•A perfect circle, right?

•Suppose you tilt the plate to a different angle, to a horizontal position, like you're planning to put food on it.

•Still a perfect circle?

•No,

•the circle is now stretched out,

•flattened into an oval.

•Do you conclude the plate has actually changed shape,

•or that it's a different object,

•not the same plate?

•Of course not.

•It looks different,

•but we perceive it as still being the same.

•Here's a different example.

•This classroom we're in its fairly large, right?

•Now from up close, from the front row,

•I appear to be relatively big,

•bigger than if you were in the last roll, right?

•But let's say you're sitting in the front row today,

•but tomorrow you're sitting in the back row.

•From back there, I'm going to look smaller,

•but you don't think I've actually gotten smaller.

•You don't think you're seeing a different professor,

•a guy who looks like me except he is smaller.

•No matter where you are, up close or far away,

•you understand without even thinking about it that I'm the same size, the same person.

•Narrator: Now listen to part of a lecture in a Biology class.

•Professor: Now many sea animals, in order to hide from predators, have over time develop different kinds of camouflage to help them blend in with their environment and avoid detection by predators.

•Picture the surface of the sea floor.

•It's as varied as the land we live on.

•It's got peaks and valleys,

•vegetation,

•rocky areas,

•and some sea animals have developed permanent colors or shapes to resemble these environmental features.

•This camouflage helps disguise them from predators by enabling them to blend into a specific part of the sea.

•For instance, take a kind of fish like the leafy seadragon.

•Well, the name says it all.

•It resembles a small, green dragon with leaflike protrusions sticking out like arms.

•And because of its color and shape,

•it blends in extremely well with green sea plants.

•So when the leafy seadragon is swimming through these plants,

•predators have trouble seeing it.

•But when it enters other environments without these green plants,

•its camouflage doesn't work anymore.

•Now other sea animals are difficult to spot anywhere in the sea, because their type of camouflage enables them to change color.

•Take the cuttlefish, a fish that is closely related to the squid and octopus.

•Unlike leafy seadragons,

•cuttlefish have not developed any particular shape to hide from predators.

•But they have a lot more mobility because their camouflage allows them to blend into any environment,

•because cuttlefish have shifting pigments that allow them to change color in a matter of seconds,

•and so they can almost instantaneously match the color of their surroundings.

•If they're swimming by green sea plants,

•they'll turn green,

•and if they're swimming over the brown sea floor,

•they'll turn brown.