[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:00.00,0:00:01.58,Default,,0000,0000,0000,,When I go to parties,
Dialogue: 0,0:00:01.58,0:00:03.36,Default,,0000,0000,0000,,it doesn't usually take very long
Dialogue: 0,0:00:03.36,0:00:04.40,Default,,0000,0000,0000,,for people to find out
Dialogue: 0,0:00:04.40,0:00:07.51,Default,,0000,0000,0000,,that I'm a scientist and I study sex.
Dialogue: 0,0:00:07.51,0:00:12.41,Default,,0000,0000,0000,,And then I get asked questions.
Dialogue: 0,0:00:12.41,0:00:15.58,Default,,0000,0000,0000,,And the questions usually have a very particular format.
Dialogue: 0,0:00:15.58,0:00:16.81,Default,,0000,0000,0000,,They start with the phrase,
Dialogue: 0,0:00:16.81,0:00:18.71,Default,,0000,0000,0000,,"A friend told me,"
Dialogue: 0,0:00:18.71,0:00:20.61,Default,,0000,0000,0000,,and then they end with the phrase,
Dialogue: 0,0:00:20.61,0:00:22.52,Default,,0000,0000,0000,,"Is this true?"
Dialogue: 0,0:00:22.52,0:00:23.91,Default,,0000,0000,0000,,And most of the time
Dialogue: 0,0:00:23.91,0:00:26.03,Default,,0000,0000,0000,,I'm glad to say that I can answer them,
Dialogue: 0,0:00:26.03,0:00:27.88,Default,,0000,0000,0000,,but sometimes I have to say,
Dialogue: 0,0:00:27.88,0:00:29.01,Default,,0000,0000,0000,,"I'm really sorry,
Dialogue: 0,0:00:29.01,0:00:30.19,Default,,0000,0000,0000,,but I don't know
Dialogue: 0,0:00:30.19,0:00:33.28,Default,,0000,0000,0000,,because I'm not that kind of a doctor."
Dialogue: 0,0:00:33.28,0:00:35.19,Default,,0000,0000,0000,,That is, I'm not a clinician,
Dialogue: 0,0:00:35.19,0:00:38.38,Default,,0000,0000,0000,,I'm a comparative biologist who studies anatomy.
Dialogue: 0,0:00:38.38,0:00:41.32,Default,,0000,0000,0000,,And my job is to look at lots of different species of animals
Dialogue: 0,0:00:41.32,0:00:44.64,Default,,0000,0000,0000,,and try to figure out how their tissues and organs work
Dialogue: 0,0:00:44.64,0:00:46.14,Default,,0000,0000,0000,,when everything's going right,
Dialogue: 0,0:00:46.14,0:00:47.75,Default,,0000,0000,0000,,rather than trying to figure out
Dialogue: 0,0:00:47.75,0:00:49.34,Default,,0000,0000,0000,,how to fix things when they go wrong,
Dialogue: 0,0:00:49.34,0:00:50.54,Default,,0000,0000,0000,,like so many of you.
Dialogue: 0,0:00:50.54,0:00:52.94,Default,,0000,0000,0000,,And what I do is I look for similarities and differences
Dialogue: 0,0:00:52.94,0:00:55.20,Default,,0000,0000,0000,,in the solutions that they've evolved
Dialogue: 0,0:00:55.20,0:00:56.79,Default,,0000,0000,0000,,for fundamental biological problems.
Dialogue: 0,0:00:56.79,0:00:58.64,Default,,0000,0000,0000,,So today I'm here to argue
Dialogue: 0,0:00:58.64,0:01:02.50,Default,,0000,0000,0000,,that this is not at all
Dialogue: 0,0:01:02.50,0:01:04.40,Default,,0000,0000,0000,,an esoteric Ivory Tower activity
Dialogue: 0,0:01:04.40,0:01:05.72,Default,,0000,0000,0000,,that we find at our universities,
Dialogue: 0,0:01:05.72,0:01:07.70,Default,,0000,0000,0000,,but that broad study
Dialogue: 0,0:01:07.70,0:01:10.66,Default,,0000,0000,0000,,across species, tissue types and organ systems
Dialogue: 0,0:01:10.66,0:01:12.29,Default,,0000,0000,0000,,can produce insights
Dialogue: 0,0:01:12.29,0:01:15.68,Default,,0000,0000,0000,,that have direct implications for human health.
Dialogue: 0,0:01:15.68,0:01:18.17,Default,,0000,0000,0000,,And this is true both of my recent project
Dialogue: 0,0:01:18.17,0:01:19.90,Default,,0000,0000,0000,,on sex differences in the brain,
Dialogue: 0,0:01:19.90,0:01:21.82,Default,,0000,0000,0000,,and my more mature work
Dialogue: 0,0:01:21.82,0:01:24.65,Default,,0000,0000,0000,,on the anatomy and function of penises.
Dialogue: 0,0:01:24.65,0:01:27.28,Default,,0000,0000,0000,,And now you know why I'm fun at parties.
Dialogue: 0,0:01:27.28,0:01:28.25,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:01:28.25,0:01:30.53,Default,,0000,0000,0000,,So today I'm going to give you an example
Dialogue: 0,0:01:30.53,0:01:32.25,Default,,0000,0000,0000,,drawn from my penis study
Dialogue: 0,0:01:32.25,0:01:33.86,Default,,0000,0000,0000,,to show you how knowledge
Dialogue: 0,0:01:33.86,0:01:35.63,Default,,0000,0000,0000,,drawn from studies of one organ system
Dialogue: 0,0:01:35.63,0:01:38.61,Default,,0000,0000,0000,,provided insights into a very different one.
Dialogue: 0,0:01:38.61,0:01:41.63,Default,,0000,0000,0000,,Now I'm sure as everyone in the audience already knows --
Dialogue: 0,0:01:41.63,0:01:45.15,Default,,0000,0000,0000,,I did have to explain it to my nine-year-old late last week --
Dialogue: 0,0:01:45.15,0:01:48.90,Default,,0000,0000,0000,,penises are structures that transfer sperm
Dialogue: 0,0:01:48.90,0:01:50.20,Default,,0000,0000,0000,,from one individual to another.
Dialogue: 0,0:01:50.20,0:01:51.70,Default,,0000,0000,0000,,And the slide behind me
Dialogue: 0,0:01:51.70,0:01:53.43,Default,,0000,0000,0000,,barely scratches the surface
Dialogue: 0,0:01:53.43,0:01:55.40,Default,,0000,0000,0000,,of how widespread they are in animals.
Dialogue: 0,0:01:55.40,0:01:57.38,Default,,0000,0000,0000,,There's an enormous amount of anatomical variation.
Dialogue: 0,0:01:57.38,0:02:01.26,Default,,0000,0000,0000,,You find muscular tubes, modified legs, modified fins,
Dialogue: 0,0:02:01.26,0:02:05.10,Default,,0000,0000,0000,,as well as the mammalian fleshy, inflatable cylinder
Dialogue: 0,0:02:05.10,0:02:06.74,Default,,0000,0000,0000,,that we're all familiar with --
Dialogue: 0,0:02:06.74,0:02:09.02,Default,,0000,0000,0000,,or at least half of you are.
Dialogue: 0,0:02:09.02,0:02:11.42,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:02:11.42,0:02:14.16,Default,,0000,0000,0000,,And I think we see this tremendous variation
Dialogue: 0,0:02:14.16,0:02:17.31,Default,,0000,0000,0000,,because it's a really effective solution
Dialogue: 0,0:02:17.31,0:02:19.47,Default,,0000,0000,0000,,to a very basic biological problem,
Dialogue: 0,0:02:19.47,0:02:21.96,Default,,0000,0000,0000,,and that is getting sperm in a position
Dialogue: 0,0:02:21.96,0:02:24.51,Default,,0000,0000,0000,,to meet up with eggs and form zygotes.
Dialogue: 0,0:02:24.51,0:02:28.46,Default,,0000,0000,0000,,Now the penis isn't actually required for internal fertiliztion,
Dialogue: 0,0:02:28.46,0:02:30.92,Default,,0000,0000,0000,,but when internal fertilization evolves,
Dialogue: 0,0:02:30.92,0:02:32.92,Default,,0000,0000,0000,,penises often follow.
Dialogue: 0,0:02:32.92,0:02:37.34,Default,,0000,0000,0000,,And the question I get when I start talking about this most often is,
Dialogue: 0,0:02:37.34,0:02:40.26,Default,,0000,0000,0000,,"What made you interested in this subject?"
Dialogue: 0,0:02:40.26,0:02:44.21,Default,,0000,0000,0000,,And the answer is skeletons.
Dialogue: 0,0:02:44.21,0:02:46.77,Default,,0000,0000,0000,,You wouldn't think that skeletons and penises
Dialogue: 0,0:02:46.77,0:02:48.62,Default,,0000,0000,0000,,have very much to do with one another.
Dialogue: 0,0:02:48.62,0:02:50.76,Default,,0000,0000,0000,,And that's because we tend to think of skeletons
Dialogue: 0,0:02:50.76,0:02:52.41,Default,,0000,0000,0000,,as stiff lever systems
Dialogue: 0,0:02:52.41,0:02:54.09,Default,,0000,0000,0000,,that produce speed or power.
Dialogue: 0,0:02:54.09,0:02:57.66,Default,,0000,0000,0000,,And my first forays into biological research,
Dialogue: 0,0:02:57.66,0:03:00.48,Default,,0000,0000,0000,,doing dinosaur paleontology as an undergraduate,
Dialogue: 0,0:03:00.48,0:03:02.03,Default,,0000,0000,0000,,were really squarely in that realm.
Dialogue: 0,0:03:02.03,0:03:05.14,Default,,0000,0000,0000,,But when I went to graduate school to study biomechanics,
Dialogue: 0,0:03:05.14,0:03:07.61,Default,,0000,0000,0000,,I really wanted to find a dissertation project
Dialogue: 0,0:03:07.61,0:03:10.51,Default,,0000,0000,0000,,that would expand our knowledge of skeletal function.
Dialogue: 0,0:03:10.51,0:03:12.31,Default,,0000,0000,0000,,I tried a bunch of different stuff.
Dialogue: 0,0:03:12.31,0:03:13.96,Default,,0000,0000,0000,,A lot of it didn't pan out.
Dialogue: 0,0:03:13.96,0:03:15.79,Default,,0000,0000,0000,,But then one day I started thinking
Dialogue: 0,0:03:15.79,0:03:17.57,Default,,0000,0000,0000,,about the mammalian penis.
Dialogue: 0,0:03:17.57,0:03:21.59,Default,,0000,0000,0000,,And it's really an odd sort of structure.
Dialogue: 0,0:03:21.59,0:03:24.41,Default,,0000,0000,0000,,Before it can be used for internal fertilization,
Dialogue: 0,0:03:24.41,0:03:25.89,Default,,0000,0000,0000,,its mechanical behavior has to change
Dialogue: 0,0:03:25.89,0:03:27.61,Default,,0000,0000,0000,,in a really dramatic fashion.
Dialogue: 0,0:03:27.61,0:03:30.21,Default,,0000,0000,0000,,Most of the time it's a flexible organ.
Dialogue: 0,0:03:30.21,0:03:31.49,Default,,0000,0000,0000,,It's easy to bend.
Dialogue: 0,0:03:31.49,0:03:33.48,Default,,0000,0000,0000,,But before it's brought into use
Dialogue: 0,0:03:33.48,0:03:34.70,Default,,0000,0000,0000,,during copulation
Dialogue: 0,0:03:34.70,0:03:36.46,Default,,0000,0000,0000,,it has to become rigid,
Dialogue: 0,0:03:36.46,0:03:38.48,Default,,0000,0000,0000,,it has to become difficult to bend.
Dialogue: 0,0:03:38.48,0:03:40.49,Default,,0000,0000,0000,,And moreover, it has to work.
Dialogue: 0,0:03:40.49,0:03:43.24,Default,,0000,0000,0000,,A reproductive system that fails to function
Dialogue: 0,0:03:43.24,0:03:46.56,Default,,0000,0000,0000,,produces an individual that has no offspring,
Dialogue: 0,0:03:46.56,0:03:49.73,Default,,0000,0000,0000,,and that individual is then kicked out of the gene pool.
Dialogue: 0,0:03:49.73,0:03:52.19,Default,,0000,0000,0000,,And so I thought, "Here's a problem
Dialogue: 0,0:03:52.19,0:03:55.44,Default,,0000,0000,0000,,that just cries out for a skeletal system --
Dialogue: 0,0:03:55.44,0:03:58.65,Default,,0000,0000,0000,,not one like this one,
Dialogue: 0,0:03:58.65,0:04:01.71,Default,,0000,0000,0000,,but one like this one --
Dialogue: 0,0:04:01.71,0:04:04.12,Default,,0000,0000,0000,,because, functionally,
Dialogue: 0,0:04:04.12,0:04:05.69,Default,,0000,0000,0000,,a skeleton is any system
Dialogue: 0,0:04:05.69,0:04:08.72,Default,,0000,0000,0000,,that supports tissue and transmits forces.
Dialogue: 0,0:04:08.72,0:04:11.07,Default,,0000,0000,0000,,And I already knew that animals like this earthworm,
Dialogue: 0,0:04:11.07,0:04:12.52,Default,,0000,0000,0000,,indeed most animals,
Dialogue: 0,0:04:12.52,0:04:13.81,Default,,0000,0000,0000,,don't support their tissues
Dialogue: 0,0:04:13.81,0:04:15.60,Default,,0000,0000,0000,,by draping them over bones.
Dialogue: 0,0:04:15.60,0:04:18.44,Default,,0000,0000,0000,,Instead they're more like reinforced water balloons.
Dialogue: 0,0:04:18.44,0:04:22.30,Default,,0000,0000,0000,,They use a skeleton that we call a hydrostatic skeleton.
Dialogue: 0,0:04:22.30,0:04:24.37,Default,,0000,0000,0000,,And a hydrostatic skeleton
Dialogue: 0,0:04:24.37,0:04:26.29,Default,,0000,0000,0000,,uses two elements.
Dialogue: 0,0:04:26.29,0:04:28.44,Default,,0000,0000,0000,,The skeletal support comes from an interaction
Dialogue: 0,0:04:28.44,0:04:30.21,Default,,0000,0000,0000,,between a pressurized fluid
Dialogue: 0,0:04:30.21,0:04:31.82,Default,,0000,0000,0000,,and a surrounding wall of tissue
Dialogue: 0,0:04:31.82,0:04:36.29,Default,,0000,0000,0000,,that's held in tension and reinforced with fibrous proteins.
Dialogue: 0,0:04:36.29,0:04:38.54,Default,,0000,0000,0000,,And the interaction is crucial.
Dialogue: 0,0:04:38.54,0:04:41.91,Default,,0000,0000,0000,,Without both elements you have no support.
Dialogue: 0,0:04:41.91,0:04:43.19,Default,,0000,0000,0000,,If you have fluid
Dialogue: 0,0:04:43.19,0:04:45.22,Default,,0000,0000,0000,,with no wall to surround it
Dialogue: 0,0:04:45.22,0:04:46.66,Default,,0000,0000,0000,,and keep pressure up,
Dialogue: 0,0:04:46.66,0:04:48.56,Default,,0000,0000,0000,,you have a puddle.
Dialogue: 0,0:04:48.56,0:04:50.66,Default,,0000,0000,0000,,And if you have just the wall
Dialogue: 0,0:04:50.66,0:04:52.39,Default,,0000,0000,0000,,with no fluid inside of it to put the wall in tension,
Dialogue: 0,0:04:52.39,0:04:54.34,Default,,0000,0000,0000,,you've got a little wet rag.
Dialogue: 0,0:04:54.34,0:04:56.98,Default,,0000,0000,0000,,When you look at a penis in cross section,
Dialogue: 0,0:04:56.98,0:04:59.41,Default,,0000,0000,0000,,it has a lot of the hallmarks
Dialogue: 0,0:04:59.41,0:05:01.46,Default,,0000,0000,0000,,of a hydrostatic skeleton.
Dialogue: 0,0:05:01.46,0:05:02.97,Default,,0000,0000,0000,,It has a central space
Dialogue: 0,0:05:02.97,0:05:04.49,Default,,0000,0000,0000,,of spongy erectile tissue
Dialogue: 0,0:05:04.49,0:05:07.07,Default,,0000,0000,0000,,that fills with fluid -- in this case blood --
Dialogue: 0,0:05:07.07,0:05:09.46,Default,,0000,0000,0000,,surrounded by a wall of tissue
Dialogue: 0,0:05:09.46,0:05:13.32,Default,,0000,0000,0000,,that's rich in a stiff structural protein called collagen.
Dialogue: 0,0:05:13.32,0:05:15.82,Default,,0000,0000,0000,,But at the time when I started this project,
Dialogue: 0,0:05:15.82,0:05:19.02,Default,,0000,0000,0000,,the best explanation I could find for penal erection
Dialogue: 0,0:05:19.02,0:05:23.30,Default,,0000,0000,0000,,was that the wall surrounded these spongy tissues,
Dialogue: 0,0:05:23.30,0:05:25.00,Default,,0000,0000,0000,,and the spongy tissues filled with blood
Dialogue: 0,0:05:25.00,0:05:28.27,Default,,0000,0000,0000,,and pressure rose and voila! it became erect.
Dialogue: 0,0:05:28.27,0:05:32.23,Default,,0000,0000,0000,,And that explained to me expansion --
Dialogue: 0,0:05:32.23,0:05:35.80,Default,,0000,0000,0000,,made sense: more fluid, you get tissues that expand --
Dialogue: 0,0:05:35.80,0:05:38.82,Default,,0000,0000,0000,,but it didn't actually explain erection.
Dialogue: 0,0:05:38.82,0:05:42.71,Default,,0000,0000,0000,,Because there was no mechanism in this explanation
Dialogue: 0,0:05:42.71,0:05:45.68,Default,,0000,0000,0000,,for making this structure hard to bend.
Dialogue: 0,0:05:45.68,0:05:48.39,Default,,0000,0000,0000,,And no one had systematically looked at the wall tissue.
Dialogue: 0,0:05:48.39,0:05:50.99,Default,,0000,0000,0000,,So I thought, wall tissue's important in skeletons.
Dialogue: 0,0:05:50.99,0:05:53.36,Default,,0000,0000,0000,,It has to be part of the explanation.
Dialogue: 0,0:05:53.36,0:05:55.89,Default,,0000,0000,0000,,And this was the point
Dialogue: 0,0:05:55.89,0:05:58.49,Default,,0000,0000,0000,,at which my graduate adviser said,
Dialogue: 0,0:05:58.49,0:06:01.87,Default,,0000,0000,0000,,"Whoa! Hold on. Slow down."
Dialogue: 0,0:06:01.87,0:06:05.24,Default,,0000,0000,0000,,Because after about six months of me talking about this,
Dialogue: 0,0:06:05.24,0:06:06.56,Default,,0000,0000,0000,,I think he finally figured out
Dialogue: 0,0:06:06.56,0:06:09.61,Default,,0000,0000,0000,,that I was really serious about the penis thing.
Dialogue: 0,0:06:09.61,0:06:12.65,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:06:12.65,0:06:14.70,Default,,0000,0000,0000,,So he sat me down, and he warned me.
Dialogue: 0,0:06:14.70,0:06:16.88,Default,,0000,0000,0000,,He was like, "Be careful going down this path.
Dialogue: 0,0:06:16.88,0:06:19.65,Default,,0000,0000,0000,,I'm not sure this project's going to pan out."
Dialogue: 0,0:06:19.65,0:06:22.18,Default,,0000,0000,0000,,Because he was afraid I was walking into a trap.
Dialogue: 0,0:06:22.18,0:06:26.100,Default,,0000,0000,0000,,I was taking on a socially embarrassing question
Dialogue: 0,0:06:26.100,0:06:29.33,Default,,0000,0000,0000,,with an answer that he thought
Dialogue: 0,0:06:29.33,0:06:31.71,Default,,0000,0000,0000,,might not be particularly interesting.
Dialogue: 0,0:06:31.71,0:06:33.24,Default,,0000,0000,0000,,And that was because
Dialogue: 0,0:06:33.24,0:06:34.76,Default,,0000,0000,0000,,every hydrostatic skeleton
Dialogue: 0,0:06:34.76,0:06:36.83,Default,,0000,0000,0000,,that we had found in nature up to that point
Dialogue: 0,0:06:36.83,0:06:38.63,Default,,0000,0000,0000,,had the same basic elements.
Dialogue: 0,0:06:38.63,0:06:39.84,Default,,0000,0000,0000,,It had the central fluid,
Dialogue: 0,0:06:39.84,0:06:41.64,Default,,0000,0000,0000,,it had the surrounding wall,
Dialogue: 0,0:06:41.64,0:06:44.78,Default,,0000,0000,0000,,and the reinforcing fibers in the wall
Dialogue: 0,0:06:44.78,0:06:47.20,Default,,0000,0000,0000,,were arranged in crossed helices
Dialogue: 0,0:06:47.20,0:06:49.26,Default,,0000,0000,0000,,around the long axis of the skeleton.
Dialogue: 0,0:06:49.26,0:06:50.58,Default,,0000,0000,0000,,So the image behind me
Dialogue: 0,0:06:50.58,0:06:52.21,Default,,0000,0000,0000,,shows a piece of tissue
Dialogue: 0,0:06:52.21,0:06:54.23,Default,,0000,0000,0000,,in one of these cross helical skeletons
Dialogue: 0,0:06:54.23,0:06:56.76,Default,,0000,0000,0000,,cut so that you're looking at the surface of the wall.
Dialogue: 0,0:06:56.76,0:06:58.48,Default,,0000,0000,0000,,The arrow shows you the long axis.
Dialogue: 0,0:06:58.48,0:07:00.33,Default,,0000,0000,0000,,And you can see two layers of fibers,
Dialogue: 0,0:07:00.33,0:07:02.03,Default,,0000,0000,0000,,one in blue and one in yellow,
Dialogue: 0,0:07:02.03,0:07:04.83,Default,,0000,0000,0000,,arranged in left-handed and right-handed angles.
Dialogue: 0,0:07:04.83,0:07:07.08,Default,,0000,0000,0000,,And if you weren't just looking at a little section of the fibers,
Dialogue: 0,0:07:07.08,0:07:09.78,Default,,0000,0000,0000,,those fibers would be going in helices
Dialogue: 0,0:07:09.78,0:07:11.53,Default,,0000,0000,0000,,around the long axis of the skeleton --
Dialogue: 0,0:07:11.53,0:07:13.66,Default,,0000,0000,0000,,something like a Chinese finger trap,
Dialogue: 0,0:07:13.66,0:07:15.56,Default,,0000,0000,0000,,where you stick your fingers in and they get stuck.
Dialogue: 0,0:07:15.56,0:07:18.65,Default,,0000,0000,0000,,And these skeletons have a particular set of behaviors,
Dialogue: 0,0:07:18.65,0:07:20.68,Default,,0000,0000,0000,,which I'm going to demonstrate in a film.
Dialogue: 0,0:07:20.68,0:07:21.83,Default,,0000,0000,0000,,It's a model skeleton
Dialogue: 0,0:07:21.83,0:07:24.01,Default,,0000,0000,0000,,that I made out of a piece of cloth
Dialogue: 0,0:07:24.01,0:07:26.57,Default,,0000,0000,0000,,that I wrapped around an inflated balloon.
Dialogue: 0,0:07:26.57,0:07:28.26,Default,,0000,0000,0000,,The cloth's cut on the bias.
Dialogue: 0,0:07:28.26,0:07:31.01,Default,,0000,0000,0000,,So you can see that the fibers wrap in helices,
Dialogue: 0,0:07:31.01,0:07:35.33,Default,,0000,0000,0000,,and those fibers can reorient as the skeleton moves,
Dialogue: 0,0:07:35.33,0:07:36.76,Default,,0000,0000,0000,,which means the skeleton's flexible.
Dialogue: 0,0:07:36.76,0:07:39.23,Default,,0000,0000,0000,,It lengthens, shortens and bends really easily
Dialogue: 0,0:07:39.23,0:07:42.78,Default,,0000,0000,0000,,in response to internal or external forces.
Dialogue: 0,0:07:42.78,0:07:44.07,Default,,0000,0000,0000,,Now my adviser's concern
Dialogue: 0,0:07:44.07,0:07:46.44,Default,,0000,0000,0000,,was what if the penile wall tissue
Dialogue: 0,0:07:46.44,0:07:48.11,Default,,0000,0000,0000,,is just the same as any other hydrostatic skeleton.
Dialogue: 0,0:07:48.11,0:07:50.04,Default,,0000,0000,0000,,What are you going to contribute?
Dialogue: 0,0:07:50.04,0:07:51.50,Default,,0000,0000,0000,,What new thing are you contributing
Dialogue: 0,0:07:51.50,0:07:53.15,Default,,0000,0000,0000,,to our knowledge of biology?
Dialogue: 0,0:07:53.15,0:07:56.57,Default,,0000,0000,0000,,And I thought, "Yeah, he does have a really good point here."
Dialogue: 0,0:07:56.57,0:07:58.32,Default,,0000,0000,0000,,So I spent a long, long time thinking about it.
Dialogue: 0,0:07:58.32,0:08:00.46,Default,,0000,0000,0000,,And one thing kept bothering me,
Dialogue: 0,0:08:00.46,0:08:02.90,Default,,0000,0000,0000,,and that's, when they're functioning,
Dialogue: 0,0:08:02.90,0:08:04.84,Default,,0000,0000,0000,,penises don't wiggle.
Dialogue: 0,0:08:04.84,0:08:07.18,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:08:07.18,0:08:10.08,Default,,0000,0000,0000,,So something interesting had to be going on.
Dialogue: 0,0:08:10.08,0:08:13.38,Default,,0000,0000,0000,,So I went ahead, collected wall tissue,
Dialogue: 0,0:08:13.38,0:08:14.98,Default,,0000,0000,0000,,prepared it so it was erect,
Dialogue: 0,0:08:14.98,0:08:17.18,Default,,0000,0000,0000,,sectioned it, put it on slides
Dialogue: 0,0:08:17.18,0:08:19.83,Default,,0000,0000,0000,,and then stuck it under the microscope to have a look,
Dialogue: 0,0:08:19.83,0:08:24.86,Default,,0000,0000,0000,,fully expecting to see crossed helices of collagen of some variety.
Dialogue: 0,0:08:24.86,0:08:27.26,Default,,0000,0000,0000,,But instead I saw this.
Dialogue: 0,0:08:27.26,0:08:30.26,Default,,0000,0000,0000,,There's an outer layer and an inner layer.
Dialogue: 0,0:08:30.26,0:08:32.81,Default,,0000,0000,0000,,The arrow shows you the long axis of the skeleton.
Dialogue: 0,0:08:32.81,0:08:35.38,Default,,0000,0000,0000,,I was really surprised at this.
Dialogue: 0,0:08:35.38,0:08:36.33,Default,,0000,0000,0000,,Everyone I showed it
Dialogue: 0,0:08:36.33,0:08:37.53,Default,,0000,0000,0000,,was really surprised at this.
Dialogue: 0,0:08:37.53,0:08:39.06,Default,,0000,0000,0000,,Why was everyone surprised at this?
Dialogue: 0,0:08:39.06,0:08:42.05,Default,,0000,0000,0000,,That's because we knew theoretically
Dialogue: 0,0:08:42.05,0:08:44.86,Default,,0000,0000,0000,,that there was another way
Dialogue: 0,0:08:44.86,0:08:47.90,Default,,0000,0000,0000,,of arranging fibers in a hydrostatic skeleton,
Dialogue: 0,0:08:47.90,0:08:50.17,Default,,0000,0000,0000,,and that was with fibers at zero degrees
Dialogue: 0,0:08:50.17,0:08:54.04,Default,,0000,0000,0000,,and 90 degrees to the long axis of the structure.
Dialogue: 0,0:08:54.04,0:08:57.60,Default,,0000,0000,0000,,The thing is, no one had ever seen it before in nature.
Dialogue: 0,0:08:57.60,0:09:00.30,Default,,0000,0000,0000,,And now I was looking at one.
Dialogue: 0,0:09:00.30,0:09:03.03,Default,,0000,0000,0000,,Those fibers in that particular orientation
Dialogue: 0,0:09:03.03,0:09:06.25,Default,,0000,0000,0000,,give the skeleton a very, very different behavior.
Dialogue: 0,0:09:06.25,0:09:07.43,Default,,0000,0000,0000,,I'm going to show a model
Dialogue: 0,0:09:07.43,0:09:09.38,Default,,0000,0000,0000,,made out of exactly the same materials.
Dialogue: 0,0:09:09.38,0:09:11.43,Default,,0000,0000,0000,,So it'll be made of the same cotton cloth,
Dialogue: 0,0:09:11.43,0:09:14.72,Default,,0000,0000,0000,,same balloon, same internal pressure.
Dialogue: 0,0:09:14.72,0:09:17.19,Default,,0000,0000,0000,,But the only difference
Dialogue: 0,0:09:17.19,0:09:19.57,Default,,0000,0000,0000,,is that the fibers are arranged differently.
Dialogue: 0,0:09:19.57,0:09:22.22,Default,,0000,0000,0000,,And you'll see that, unlike the cross helical model,
Dialogue: 0,0:09:22.22,0:09:25.17,Default,,0000,0000,0000,,this model resists extension and contraction
Dialogue: 0,0:09:25.17,0:09:26.62,Default,,0000,0000,0000,,and resists bending.
Dialogue: 0,0:09:26.62,0:09:27.66,Default,,0000,0000,0000,,Now what that tells us
Dialogue: 0,0:09:27.66,0:09:29.75,Default,,0000,0000,0000,,is that wall tissues are doing so much more
Dialogue: 0,0:09:29.75,0:09:32.26,Default,,0000,0000,0000,,than just covering the vascular tissues.
Dialogue: 0,0:09:32.26,0:09:35.75,Default,,0000,0000,0000,,They're an integral part of the penile skeleton.
Dialogue: 0,0:09:35.75,0:09:38.29,Default,,0000,0000,0000,,If the wall around the erectile tissue wasn't there,
Dialogue: 0,0:09:38.29,0:09:40.45,Default,,0000,0000,0000,,if it wasn't reinforced in this way,
Dialogue: 0,0:09:40.45,0:09:41.60,Default,,0000,0000,0000,,the shape would change,
Dialogue: 0,0:09:41.60,0:09:43.99,Default,,0000,0000,0000,,but the inflated penis would not resist bending,
Dialogue: 0,0:09:43.99,0:09:46.04,Default,,0000,0000,0000,,and erection simply wouldn't work.
Dialogue: 0,0:09:46.04,0:09:48.64,Default,,0000,0000,0000,,It's an observation with obvious medical applications
Dialogue: 0,0:09:48.64,0:09:50.42,Default,,0000,0000,0000,,in humans as well,
Dialogue: 0,0:09:50.42,0:09:53.35,Default,,0000,0000,0000,,but it's also relevant in a broad sense, I think,
Dialogue: 0,0:09:53.35,0:09:55.79,Default,,0000,0000,0000,,to the design of prosthetics, soft robots,
Dialogue: 0,0:09:55.79,0:09:56.85,Default,,0000,0000,0000,,basically anything
Dialogue: 0,0:09:56.85,0:10:00.17,Default,,0000,0000,0000,,where changes of shape and stiffness are important.
Dialogue: 0,0:10:00.17,0:10:01.92,Default,,0000,0000,0000,,So to sum up:
Dialogue: 0,0:10:01.92,0:10:03.14,Default,,0000,0000,0000,,Twenty years ago,
Dialogue: 0,0:10:03.14,0:10:04.89,Default,,0000,0000,0000,,I had a college adviser tell me,
Dialogue: 0,0:10:04.89,0:10:06.94,Default,,0000,0000,0000,,when I went to the college and said,
Dialogue: 0,0:10:06.94,0:10:08.09,Default,,0000,0000,0000,,"I'm kind of interested in anatomy,"
Dialogue: 0,0:10:08.09,0:10:09.97,Default,,0000,0000,0000,,they said, "Anatomy's a dead science."\N
Dialogue: 0,0:10:09.97,0:10:12.59,Default,,0000,0000,0000,,He couldn't have been more wrong.
Dialogue: 0,0:10:12.59,0:10:15.32,Default,,0000,0000,0000,,I really believe that we still have a lot to learn
Dialogue: 0,0:10:15.32,0:10:18.45,Default,,0000,0000,0000,,about the normal structure and function of our bodies.
Dialogue: 0,0:10:18.45,0:10:21.27,Default,,0000,0000,0000,,Not just about its genetics and molecular biology,
Dialogue: 0,0:10:21.27,0:10:24.67,Default,,0000,0000,0000,,but up here in the meat end of the scale.
Dialogue: 0,0:10:24.67,0:10:26.10,Default,,0000,0000,0000,,We've got limits on our time.
Dialogue: 0,0:10:26.10,0:10:28.37,Default,,0000,0000,0000,,We often focus on one disease,
Dialogue: 0,0:10:28.37,0:10:29.55,Default,,0000,0000,0000,,one model, one problem,
Dialogue: 0,0:10:29.55,0:10:31.12,Default,,0000,0000,0000,,but my experience suggests
Dialogue: 0,0:10:31.12,0:10:32.90,Default,,0000,0000,0000,,that we should take the time
Dialogue: 0,0:10:32.90,0:10:35.47,Default,,0000,0000,0000,,to apply ideas broadly between systems
Dialogue: 0,0:10:35.47,0:10:37.34,Default,,0000,0000,0000,,and just see where it takes us.
Dialogue: 0,0:10:37.34,0:10:40.94,Default,,0000,0000,0000,,After all, if ideas about invertebrate skeletons
Dialogue: 0,0:10:40.94,0:10:42.41,Default,,0000,0000,0000,,can give us insights
Dialogue: 0,0:10:42.41,0:10:44.49,Default,,0000,0000,0000,,about mammalian reproductive systems,
Dialogue: 0,0:10:44.49,0:10:48.54,Default,,0000,0000,0000,,there could be lots of other wild and productive connections
Dialogue: 0,0:10:48.54,0:10:50.99,Default,,0000,0000,0000,,lurking out there just waiting to be found.
Dialogue: 0,0:10:50.99,0:10:52.84,Default,,0000,0000,0000,,Thank you.
Dialogue: 0,0:10:52.84,0:10:56.23,Default,,0000,0000,0000,,(Applause)