An unusual feature that some parrots have that Don tries to apply to himself until Yael sets him straight.
D: Well, I'm all set for my date. How do I look?
Y: I see you've shaved. And you're wearing a sporty new shirt and tie. I think you'll do fine.
D: No, no . . . I mean, is my head glowing?
Y: . . . Is your head glowing? No, your head isn't glowing.
D: Rats. I've been trying all morning.
Y: Why have you been trying to make you head glow?
D: Well, it works for parrots.
Y: Parrots have glowing heads?
D: They sure do. Some birds in the parrot family have feathers on their heads that fluoresce. That means these special feathers take in energy from the sun in the for on ultraviolet light and then re-emit that energy.
Y: But we can't see ultraviolet light.
D: The energy is re-emitted in longer wavelengths that parrots can see--and humans, too.
Y: What does this have to do with dating?
D: Certain kinds of parrots use their fluorescing feathers to attract mates.
Y: Yeah? How do we know that?
D: A simple experiment done by Kathryn Arnold at the University of Glasgow in Scotland. She covered the glowing feathers on some parrots with a jelly that blocks UV-light. Others parrots got a jelly that was transparent. Guess which ones were more sexually attractive to other parrots?
Y: The ones that glowed?
D: Nothing like a little glowing-head-action to start your date off right. Well, wish me luck.
Y: Just be yourself. And better not mention the glowing head thing.