[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:00.00,0:00:02.60,Default,,0000,0000,0000,,(Mosquito buzzing)
Dialogue: 0,0:00:02.63,0:00:05.49,Default,,0000,0000,0000,,Greg Gage: We've all heard\Nthe annoying sound of a mosquito,
Dialogue: 0,0:00:05.52,0:00:07.74,Default,,0000,0000,0000,,and we will stop at nothing\Nto make it go away.
Dialogue: 0,0:00:07.76,0:00:09.67,Default,,0000,0000,0000,,While this sound may be maddening to us,
Dialogue: 0,0:00:09.69,0:00:11.61,Default,,0000,0000,0000,,perhaps it's music to a mosquito's ears.
Dialogue: 0,0:00:11.64,0:00:15.87,Default,,0000,0000,0000,,The mosquito's nervous system has almost\Nas many sensory auditory cells as we do.
Dialogue: 0,0:00:16.37,0:00:18.91,Default,,0000,0000,0000,,But why would they have\Nso many in such a small body,
Dialogue: 0,0:00:18.93,0:00:21.48,Default,,0000,0000,0000,,and why would they need to be\Nso sensitive to sounds?
Dialogue: 0,0:00:21.50,0:00:22.70,Default,,0000,0000,0000,,The answer is love.
Dialogue: 0,0:00:22.72,0:00:24.64,Default,,0000,0000,0000,,[DIY Neuroscience]
Dialogue: 0,0:00:24.66,0:00:27.60,Default,,0000,0000,0000,,(Music)
Dialogue: 0,0:00:27.64,0:00:29.73,Default,,0000,0000,0000,,As humans, we do a lot\Nto attract each other.
Dialogue: 0,0:00:29.76,0:00:31.15,Default,,0000,0000,0000,,Some things are conscious --
Dialogue: 0,0:00:31.17,0:00:33.27,Default,,0000,0000,0000,,we put on makeup\Nand make sure we smell nice.
Dialogue: 0,0:00:33.30,0:00:34.52,Default,,0000,0000,0000,,And some are unconscious.
Dialogue: 0,0:00:34.55,0:00:38.17,Default,,0000,0000,0000,,You may unconsciously point your body\Nor even sit closer to someone you like.
Dialogue: 0,0:00:38.19,0:00:41.58,Default,,0000,0000,0000,,These are courtship behaviors,\Nand a lot of animals have them.
Dialogue: 0,0:00:41.60,0:00:43.20,Default,,0000,0000,0000,,And mosquitoes are no different.
Dialogue: 0,0:00:43.23,0:00:46.52,Default,,0000,0000,0000,,So Haley's been spending her summer\Nbravely listening to mosquitoes,
Dialogue: 0,0:00:46.55,0:00:48.47,Default,,0000,0000,0000,,and what she observed may surprise you.
Dialogue: 0,0:00:48.49,0:00:51.92,Default,,0000,0000,0000,,So we want to investigate\Nhow the mosquitoes make their song.
Dialogue: 0,0:00:51.95,0:00:54.49,Default,,0000,0000,0000,,So Haley, how do we record\Ntheir wing beats?
Dialogue: 0,0:00:54.51,0:00:56.30,Default,,0000,0000,0000,,Haley Smith: We need to tether them.
Dialogue: 0,0:00:56.32,0:01:01.10,Default,,0000,0000,0000,,First, we anesthetize them\Nin a fridge or a bed of ice.
Dialogue: 0,0:01:01.12,0:01:04.58,Default,,0000,0000,0000,,And then I transfer them\Nto this petri dish of ice,
Dialogue: 0,0:01:04.60,0:01:06.50,Default,,0000,0000,0000,,just to get them even more anesthetized.
Dialogue: 0,0:01:06.53,0:01:10.05,Default,,0000,0000,0000,,Next, I take an insect pin,
Dialogue: 0,0:01:10.08,0:01:14.55,Default,,0000,0000,0000,,and what I do is put a tiny little dab\Nof superglue on this pin.
Dialogue: 0,0:01:14.58,0:01:18.32,Default,,0000,0000,0000,,I want to make sure that I get it\Non his thorax above his wings
Dialogue: 0,0:01:18.34,0:01:21.80,Default,,0000,0000,0000,,so that when he is suspended,\Nhis wings are still free to move.
Dialogue: 0,0:01:21.82,0:01:22.98,Default,,0000,0000,0000,,So here's one down.
Dialogue: 0,0:01:23.00,0:01:25.53,Default,,0000,0000,0000,,It's really hard to catch\Nmale mosquitoes in the wild
Dialogue: 0,0:01:25.55,0:01:29.80,Default,,0000,0000,0000,,because females are the only mosquitoes\Nthat are attracted to humans.
Dialogue: 0,0:01:29.83,0:01:31.42,Default,,0000,0000,0000,,They feed on human blood.
Dialogue: 0,0:01:31.45,0:01:36.77,Default,,0000,0000,0000,,And now, we can try to get\Nsome recordings from them.
Dialogue: 0,0:01:36.79,0:01:39.09,Default,,0000,0000,0000,,So this is the stand\Nthat I use to hold them.
Dialogue: 0,0:01:39.11,0:01:41.27,Default,,0000,0000,0000,,I like to place it\Nright over the microphone
Dialogue: 0,0:01:41.29,0:01:44.08,Default,,0000,0000,0000,,so that I can get a recording\Nof the buzzing that you hear.
Dialogue: 0,0:01:44.11,0:01:47.11,Default,,0000,0000,0000,,That sound is generated\Nby how fast they're beating their wings.
Dialogue: 0,0:01:47.13,0:01:48.37,Default,,0000,0000,0000,,This is a male.
Dialogue: 0,0:01:48.40,0:01:52.07,Default,,0000,0000,0000,,The males have very bushy antennae,\Nand they look kind of feathery.
Dialogue: 0,0:01:52.10,0:01:54.61,Default,,0000,0000,0000,,And they are also much smaller.
Dialogue: 0,0:01:54.64,0:01:57.90,Default,,0000,0000,0000,,GG: So he's flying at around 600 hertz.
Dialogue: 0,0:01:57.92,0:02:00.40,Default,,0000,0000,0000,,Can we try a female mosquito?
Dialogue: 0,0:02:00.42,0:02:02.45,Default,,0000,0000,0000,,HS: Sure, here we go.
Dialogue: 0,0:02:02.48,0:02:08.13,Default,,0000,0000,0000,,(Mosquito buzzing, lower pitch)
Dialogue: 0,0:02:08.15,0:02:09.40,Default,,0000,0000,0000,,GG: Wow.
Dialogue: 0,0:02:09.42,0:02:11.96,Default,,0000,0000,0000,,HS: This is a much lower\Nfrequency than the male.
Dialogue: 0,0:02:11.98,0:02:14.12,Default,,0000,0000,0000,,GG: Yeah, it sounds completely different.
Dialogue: 0,0:02:14.14,0:02:15.100,Default,,0000,0000,0000,,(Mosquito buzzing)
Dialogue: 0,0:02:16.02,0:02:18.50,Default,,0000,0000,0000,,(Mosquito buzzing, lower pitch)
Dialogue: 0,0:02:18.52,0:02:20.89,Default,,0000,0000,0000,,So is it because they're\Ntwo different mosquitoes,
Dialogue: 0,0:02:20.91,0:02:22.59,Default,,0000,0000,0000,,or because they're male and female?
Dialogue: 0,0:02:22.62,0:02:24.53,Default,,0000,0000,0000,,HS: It's because\Nthey're male and female.
Dialogue: 0,0:02:24.56,0:02:26.20,Default,,0000,0000,0000,,GG: Alright, let's verify that.
Dialogue: 0,0:02:26.22,0:02:28.81,Default,,0000,0000,0000,,Can you bring in another female\Nand see if she sounds
Dialogue: 0,0:02:28.83,0:02:30.71,Default,,0000,0000,0000,,like mosquito A or mosquito B?
Dialogue: 0,0:02:30.73,0:02:31.88,Default,,0000,0000,0000,,HS: Yeah.
Dialogue: 0,0:02:31.91,0:02:33.66,Default,,0000,0000,0000,,(Mosquito buzzing, lower pitch)
Dialogue: 0,0:02:33.68,0:02:35.76,Default,,0000,0000,0000,,And again, she is much lower\Nthan the male.
Dialogue: 0,0:02:35.78,0:02:37.48,Default,,0000,0000,0000,,GG: Yeah, she sounds different.
Dialogue: 0,0:02:37.50,0:02:43.15,Default,,0000,0000,0000,,(Mosquito buzzing, lower pitch)
Dialogue: 0,0:02:43.17,0:02:44.68,Default,,0000,0000,0000,,Yeah, she's spot-on 400.
Dialogue: 0,0:02:44.70,0:02:46.83,Default,,0000,0000,0000,,HS: She really is.\NGG: That's really bizarre.
Dialogue: 0,0:02:46.86,0:02:50.60,Default,,0000,0000,0000,,HS: The females are at a much\Nlower pitch. They were around 400 hertz.
Dialogue: 0,0:02:50.62,0:02:52.91,Default,,0000,0000,0000,,HS: And all of the females\Nwere around that, too.
Dialogue: 0,0:02:52.94,0:02:54.75,Default,,0000,0000,0000,,They were much larger than the males,
Dialogue: 0,0:02:54.77,0:02:58.22,Default,,0000,0000,0000,,so they didn't have to flap their wings\Nas fast to stay in free flight.
Dialogue: 0,0:02:58.24,0:03:01.24,Default,,0000,0000,0000,,GG: So they have larger wings,\Nso they're flapping slower.
Dialogue: 0,0:03:01.26,0:03:04.58,Default,,0000,0000,0000,,And you noticed that all the females\Nhave the same frequency, roughly?
Dialogue: 0,0:03:04.61,0:03:07.02,Default,,0000,0000,0000,,And the males do, too.\NThat's kind of interesting.
Dialogue: 0,0:03:07.04,0:03:08.56,Default,,0000,0000,0000,,So that must mean something.
Dialogue: 0,0:03:08.59,0:03:12.13,Default,,0000,0000,0000,,Well, let's see what happens when\Nwe put the male and the female together.
Dialogue: 0,0:03:12.16,0:03:16.15,Default,,0000,0000,0000,,(Mosquitoes buzzing; pitch varies)
Dialogue: 0,0:03:16.18,0:03:18.51,Default,,0000,0000,0000,,HS: When I put them\Ninto the same hearing range,
Dialogue: 0,0:03:18.54,0:03:21.32,Default,,0000,0000,0000,,I noticed that they were kind of\Nchanging their tones.
Dialogue: 0,0:03:21.34,0:03:23.60,Default,,0000,0000,0000,,It was kind of more dull, almost.
Dialogue: 0,0:03:23.63,0:03:25.21,Default,,0000,0000,0000,,(Mosquitoes buzzing)
Dialogue: 0,0:03:25.23,0:03:28.97,Default,,0000,0000,0000,,And when I put it back in my spectrogram\Nto see their interaction,
Dialogue: 0,0:03:28.99,0:03:31.32,Default,,0000,0000,0000,,they were meeting at the same tone.
Dialogue: 0,0:03:31.34,0:03:32.80,Default,,0000,0000,0000,,GG: OK, pause.
Dialogue: 0,0:03:32.83,0:03:35.12,Default,,0000,0000,0000,,The males and females are singing a duet,
Dialogue: 0,0:03:35.14,0:03:38.57,Default,,0000,0000,0000,,meaning that they adjust their wings\Nto be able to produce a common tone.
Dialogue: 0,0:03:38.60,0:03:41.27,Default,,0000,0000,0000,,You have the male singing up here at G,
Dialogue: 0,0:03:41.30,0:03:44.15,Default,,0000,0000,0000,,and you have the female\Nsinging down here at D,
Dialogue: 0,0:03:44.17,0:03:45.46,Default,,0000,0000,0000,,and when they get together,
Dialogue: 0,0:03:45.48,0:03:48.70,Default,,0000,0000,0000,,you're saying that they change\Nthe frequency of their wings
Dialogue: 0,0:03:48.72,0:03:50.18,Default,,0000,0000,0000,,such that they come together?
Dialogue: 0,0:03:50.21,0:03:52.65,Default,,0000,0000,0000,,HS: Yeah, exactly.\NGG: And they sort of sing a duet.
Dialogue: 0,0:03:52.67,0:03:57.78,Default,,0000,0000,0000,,(Mosquitoes gradually\Nadjusting to identical pitch)
Dialogue: 0,0:03:57.80,0:04:00.12,Default,,0000,0000,0000,,HS: They're communicating\Nto let each other know
Dialogue: 0,0:04:00.14,0:04:02.30,Default,,0000,0000,0000,,that they've basically\Nfound a potential mate.
Dialogue: 0,0:04:02.32,0:04:03.47,Default,,0000,0000,0000,,GG: So in other words,
Dialogue: 0,0:04:03.50,0:04:06.49,Default,,0000,0000,0000,,the female tends to choose\Na male that best sings her duet.
Dialogue: 0,0:04:06.52,0:04:08.66,Default,,0000,0000,0000,,And studies have found\Nthat if she's pregnant,
Dialogue: 0,0:04:08.68,0:04:09.92,Default,,0000,0000,0000,,she doesn't even bother.
Dialogue: 0,0:04:10.66,0:04:13.34,Default,,0000,0000,0000,,So if we can understand\Nthe mosquito mating behavior,
Dialogue: 0,0:04:13.37,0:04:17.44,Default,,0000,0000,0000,,we may be able to disrupt it in the wild\Nand prevent diseases like malaria.
Dialogue: 0,0:04:17.47,0:04:21.35,Default,,0000,0000,0000,,But for now, the next time\Nyou hear a mosquito buzzing,
Dialogue: 0,0:04:21.37,0:04:24.64,Default,,0000,0000,0000,,just pause and remember she may be in love
Dialogue: 0,0:04:24.67,0:04:26.22,Default,,0000,0000,0000,,and she may be singing her song,
Dialogue: 0,0:04:26.25,0:04:28.18,Default,,0000,0000,0000,,looking for her perfect match.
Dialogue: 0,0:04:28.20,0:04:29.20,Default,,0000,0000,0000,,(Mosquito buzzing)
Dialogue: 0,0:04:29.23,0:04:30.38,Default,,0000,0000,0000,,(Smack)