[00:00.00]Narrator: Listen to a conversation between a student and his biology professor.
[00:07.57]Student: Professor Landrea.
[00:09.90]Professor: Hi, Dennis. You are right on time. [00:11.75]Come on in and have a seat.
[00:13.04]Student: Great! Thanks.
[00:16.57]Professor: So like I told you in class, I just wanted to take a few minutes to meet with everyone to make sure your class presentations for next week are all in order and coming along well. [00:26.97]And as you know, you are supposed to report on some area of recent research in genetics, something…you know…original.
[00:33.54]Student: Well, I think I found just the thing! [00:36.13]It actually occurred to me a couple nights ago while I was eating dinner in the cafeteria. [00:40.40]Tell me professor, do you like broccoli?
[00:42.95]Professor: Broccoli? You mean the vegetable broccoli?
[00:47.39]Professor: Well, I guess not really.
[00:51.40]Student: Me neither. I have never liked it or most other vegetables for that matter…Brussels sprouts, asparagus, cauliflower…you name it. [00:58.86]They just taste bitter and…well…nasty to me.[01:02.16] My mother always called me a picky eater.
[01:06.64]Student: And so I got to wondering: I mean, I am obviously not the only person like this. [01:11.81]So is this just because of some…like trauma from our childhoods? [01:16.12]Some bad experience we’ve had with vegetables? [01:18.61]Or could there be some genetic explanation for why some people are picky eaters and others aren’t?
[01:23.98]Professor: OK. I see. Well, I suppose it’s a possibility.
[01:28.13]Student: Actually, it turns out it’s more than a possibility.[01:30.98] I started doing some research in the library that night and I found out that a biologist at the National Institutes of Health has been looking at that very question recently.
[01:40.20]Professor: Well, I guess that’s not too surprising. [01:42.57]And this is great stuff actually. [01:45.27]So what’s the verdict?
[01:46.85]Student: Well, this guy seems to have discovered a particular gene that actually makes it possible for people to taste the bitterness in certain green vegetables. [01:54.92]But people who have a mutation in that gene cannot taste the bitterness.
[01:59.15]Professor: Well…that’s certainly fascinating! [02:02.69]But…so this biologist is basically claiming that people who like to eat these vegetables actually have some sort of sensory deficit? [02:10.97]Sort of makes us picky eaters than normal ones, doesn’t it? [02:14.66]I mean, that’s kind of turning things on their head, isn’t it?
[02:17.48]Student: Well…then again, it wouldn’t be the first time, would it? [02:20.69]Think of it this way: humans originally needed to have a stronger sensitivity to bitter-tasting foods so they could learn what plants were good for them and which ones might be poisonous. [02:30.59]But at some point, as people figured out what they could safely eat, this need became less crucial and a segment of the population lost that ability.
[02:39.09]Professor: OK. Well, you make a compelling case. [02:42.82]I can’t wait to hear more about this when you deliver your report.