[00:00.00]Listen to part of a conversation between a student and her biology professor.
[00:06.53]Professor：So, the assignment is to reproduce one of the animal camouflage experiments we read about in our textbook. [00:13.10]Which experiment did you pick?
[00:15.10]Student:Well, I was wondering if I can try to reproduce an experiment that’s……kind of the opposite of what was discussed in the textbook?
[00:23.02]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? [00:31.51]Em? Tell me more.
[00:33.66]Student:Well, I got the idea from one of the journals you said we should look at. [00:37.21]It’s an experiment about ah……they called them eyes spots in the article?
[00:42.95]Professor:Eyes spots, sure. [00:44.51]The patterns on the wings of moths and butterflies that are generally believed to scare off predators because they look like big eyes?
[00:51.77]Student:Yeah. Except the article was about the experiment that disputes that theory.
[00:56.14]Professor:Well, we know that the markings do scare the birds but the idea that the spots looked like eyes is……well, that is just a commonly held belief.
[01:06.12]Student:So, that’s not even based on research?
[01:09.33]Professor:Well, this whole idea of moths and butterfly markings being scary because they looked like eyes, rest on how we imagine the predators, like birds, perceive the markings.[01:20.62] And we can never really know that. [01:22.79]All we can do is observe bird behavior. [01:25.79]But tell me more about the experiment.
[01:28.34]Student: Ok. It said the experiment looked at the shapes of the markings on moths’ wings. [01:33.10]The researchers wanted to know if the markings that were round and eye-shaped were more effective in deterring predators than square and rectangular markings.
[01:42.44]Student:Yeah. So they attached food to paper models of moths with different shaped marks drawn on the wings to see how birds reacted. [01:49.94]And what’s interesting is they realized the round marks were not more effective in scaring bird than other shapes.
[01:56.55]Professor:Were they less effective?
[01:58.44]Student:No, they were about the same. [02:00.77]But what researchers did determine is that larger markings were more effective than smaller markings in scaring off prey. [02:07.23]They call this phenomenon “visual aliveness”.
[02:10.49]Professor:Visual aliveness. Um. [02:12.62]Well, I guess that it is not all that shocking if you think about it.
[02:16.80]Student:So anyway, is it ok? [02:19.44]Can I repeat this experiment and write about it?
[02:22.25]Professor:Yes, I think that’ll work. [02:24.46]The problem I foresee is……well……where? [02:28.16]This is an urban campus, you’ll have a hard time finding a good place to set up the experiment.
[02:33.29]Student:Oh, I wasn’t planning on doing it on campus. [02:36.17]I’m going home for spring break and my family lives in the country, far from the near city. [02:40.77]I can set it up in the backyard.
[02:42.60]Professor:Good idea. [02:43.66]Except one week is not a lot of time, so you will need to make some adjustments to have enough data. [02:49.99]I’d set up the experiment near bird feeder and get in as much observation time as you can.