SGU Episode 355

Introduction
You're listening to the Skeptics' Guide to the Universe, your escape to reality.

S: Hello and welcome to the Skeptics' Guide to the Universe. This is your show for May 5th, 2012 and this your host, Steven Novella. Joining me this week are Bob Novella...

B: Hey everybody.

S: Rebecca Watson...

R: Hello, everyone.

S: Jay Novella...

J: Hey, guys.

S: Evan Bernstein...

E: Good evening, everybody.

S: And we have a couple of special guests with us today. ...

SS: Hi.

S: Seth, welcome back to the Skeptics' Guide.

SS: It's a pleasure.

S: And James Randi. James, welcome back.

JR: Bon soir.

E: Ooh.

R: Classy. Classiest one in the room.

E: Oh wait.

S: Seth is with SETI, the Search for Extraterrestrial Intelligence. We've had you on the show a couple of times before. Again, it's always fun to have you on the show. How have things been going over at SETI?

SS: Well, we only found a last week. So it was hardly worth it.

S: Oh.

R: Eh, keep going.

E: Boring!

SS: (laughs) No, we're busy looking at stars that are known to have planets, discovered by NASA's. So, in a way that's quite exciting.

E: Kepler rocks.

S: Is that changing the way you're doing things? The fact that we're discovering actual planets around other stars?

SS: Well, clearly if you point the antennas in the direction of a star that's known to have planets, that's a better bet than pointing it at a random star. But I think that the most important thing that we're learning from Kepler is what fraction of stars have planets, and it looks like that fraction is so high that you can just point them anywhere, at any star, with a reasonably good chance that you're at least pointing at something that has some encircling worlds.

S: We may talk about that some more in a little while, but let's first get to This Day in Skepticism, Rebecca?

R: Well wait, can we first&mdash;I just want to point out that we have another special guest.

S: And who is that?

R: It's a special guest that is composed of twenty-some fans of SGU.

S: Are they making a human caterpillar?

(laughter)

E: What has 20 heads and 200 toes?

R: I'll take, "things Steve will edit it out of the podcast" for $200.

(laughter)

B: Call it a meta-guest.

R: Can we hear some applause from our audience, so...

(applause)

R: All right.

E: I don't even need to raise the microphone.

J: There's people upstairs that are having sex in a suite, and they heard that.

E: And they're saying thank you very much, yeah.

(laughter)

R: Yeah, I just want our podcast listeners to know in case they hear people in the background; we did this once before.

S: Yep, way to break the. Good job.

R: It's what I do. It's what I do.

S: Is there a fourth wall in podcasting? I don't know.

E: There is now.

R: I enjoy these shows. It's only the second one we've done, but...

S: Yeah, you love a crowd; I know, Rebecca.

E: Shut up.

This Day in Skepticism (2:40)

 * May 5, 1961: Alan Shepard becomes the first American in space

S: So...

R: So this day in history. Things happened.

S: This day in science, skepticism and history.

R: Well, today is the anniversary of the first US space flight. Steve, did you know that?

S: I did. Sam Shepard, right?

E: Sam Shepard? Isn't he an actor?

R: (laughs) Close. Uh, yes. .

S: Alan Shepard!

E: That's his brother.

R: You might have heard of him. Made a 15-minute sub-ordab... orb... (stammers)

S: Barely counted.

R: Sub-orbital.

S: Sub-orbital.

J: Well, how high up did he go?

R: Barely? I'd like to see you do it!

E: Four foot one.

S: Well, you know.

J: Do you know how high up he went?

S: 115 miles.

E: Meh.

R: Steve just knew that. He's got it in front of him.

B: He was the first American, you said? And what was he in terms of humanity? Was he second or third or fourth? I mean, we were beaten by the Russians.

E: The Soviets beat us?

SS: Yeah, went up.

R: Yeah.

B: Yuri, but after him was there anybody after Yuri?

SS: Then there were an assortment of zoological specimens that went up.

JR: for example. We forgot Laika?

B: Well, yeah monkeys and dogs, right?

E: I heard about that recently.

S: Laika the dog, right.

B: But he was the second person, then? Shepherd was the second?

SS: I'm not sure that Alan Shepherd was the second person; the Russians may have had somebody else.

B: More than one? OK.

S: Didn't a couple die and they didn't talk about it?

SS: Well, that makes a good story.

S: Yeah.

J: (laughs)

E: It does make a good story, I agree.

B: Did they erase them from pictures and stuff? I remember seeing pictures of like... pre-Photoshop. It doesn't look very good, you know.

SS: Yeah the trading cards were taken back.

(laughter)

J: So OK, so&mdash;

B: What did they call it before Photoshop?

J: &mdash;what did they send him?

SS: Photographs.

J: &mdash;and I can't even picture what the capsule looks like; for some reason I don't...

S: But that was the, right? Yeah.

R: Yeah, it was the, riding on the Mercury.

J: So it was a single-man capsule.

S: Yeah. Right.

R: Yeah, mmhmm. I was just in DC at the Smithsonian and they have all those capsules on display and it's really remarkable to see how tightly they stuff them in there and every square inch is utilised for something.

B: Dials and, yeah.

JR: Well, that's budget problems.

S: Yeah.

R: Yeah. No, it is&mdash;it's really cool&mdash;it's really amazing. And it's particularly amazing that the things on display at the Smithsonian are the actual&mdash;these things went into space! They're right there on the other side of that bit of plastic keeping you from manhandling it.

J: Isn't that the one where the guy had to pee in his spacesuit?

S: Yes.

J: That guy was one of the astronauts that did the the Mercury missions.

S: And they gave him permission to pee.

J: Right.

R: Have you read 's ? I feel like you would really like it, Jay, because it's mostly about astronauts pooping in space.

(laughter)

R: I'd say like 90% of it is about poop. It's...

J: Like, the evolution of how pooping has changed in space?

R: Yeah about&mdash;yeah, like&mdash;and the serious scientists who had spent a lot of time figuring out the easiest way to poop into a bag. You know? They tried diapers and the astronauts absolutely hated it. The astronauts would not eat, specifically because pooping was such a major issue.

J: I've got to know; how do they do it now?

R: Uh, oh jeez.

JR: Is this one of our classier shows?

(laughter)

E: This is a step up, yeah.

B: Rebecca, was it Packing for Mars or Crapping for Mars? What was the title?

R: You took it down another notch. Good job.

B: I had to go there, come on.

J: It was Impacting for Mars.

S: It was Impacting for Mars.

J: Yeah.

E: OK.

R: Yeah. You'll have to read the book to find out what they do now.

J: All right. Good answer.

S: OK.

E: That's a shitty ending.

R: Mary Roach owes me a dollar.

SGU 7 Year Anniversary (5:53)
S: May 5th, though, is another momentous day in Science and Skepticism.

R: Mmhmm.

E: May 5th, seven years ago. Episode one! Of the SGU!

(cheers)

E: A classic in its own right. In its own right.

R: It's like&mdash;seriously, if you guys haven't heard it, you should.

J: It's so bad.

E: You've got to go back.

R: It's like Perry yelling, "what's happening!? I can't hear you."

E: And Steve saying, "Perry, turn your mic down".

R: Turn your mic down, yeah.

E: Before we got the whole editing thing down to a science. Um yeah, it was rough. But it was, you know, nostalgic. If nothing else.

J: It doesn't feel like seven years; it really did go by fast.

S: Yeah.

J: I mean, are we going to be doing this seven years from now?

R: No, you guys... a grown man came up to me today and said, "I'm a big fan, I've been listening to you since I was 14."

(laughter)

E: Whoa.

R: What!? Oooh.

B: Oh boy.

R: Terrifying.

S: 14 what?

(laughter)

Capturing Rogue Planets (6:57)

 * Phys.org: Some stars capture rogue planets

S: Bob, you want to talk about rogue planets?

B: I guess.

(laughter)

R: Yeah, you know how it is; how we're always pushing on Bob. Could you please talk about astronomy?

S: And make it long.

B: But I read a recent article about billions of stars in the Milky Way having captured rogue planets. They did some&mdash;I think it's Harvard and Smithsonian Institution scientists. They did some sort of simulation. They ran a simulation of young star clusters, and they put a lot of rogue planets in there and they had a lot of stars and they found that 3-6% of the stars captured these rogue planets. And so they&mdash;from that they kind of extrapolated that, oh there could be billions and billions of stars that have rogue planets, planets that didn't evolve with the solar system but were just kind of captured. And so, I did a little bit of research on rogue planets and they're kind of interesting. They can occur naturally, solar systems have planets, and as Seth was saying earlier, Kepler is seeing so many planets out there. You could have weird gravitational interactions that just kind of like catapult out a planet and it becomes a rogue planet. And apparently, rogue planets can be created also just kind of like on their own, which I thought was kind of weird; I never read that before.

S: Not as part of a solar system?

B: Not as part of a solar system, but just kind of like coalescing out of whatever in space and becoming a planet that becomes a rogue planet from day one, which I had never heard about.

S: Is that just like a failed star? Is that what they're trying to...

B: Well, really failed because it's planetary. A really lame star.

JR: That's a real failure.

(laughter)

B: I think they actually call it a sub-brown dwarf.

S: Sub-brown dwarf.

E: Wow.

B: But it's planetary in scale. So it's like, well OK.

J: So is it a gas giant?

B: No, it's...

S: Like a Jupiter?

B: I think even smaller, even smaller than that. But I guess it could be Jupiter-sized, but my impression was that it was smaller than Jupiter sized. But they still call it sub-brown dwarf because it never formed within a solar system.

S: But is it the same processes forming a solar system, just that the centre never was big enough to get to, to develop into a star? So you just have a bunch of planets with no star? Is that what they're talking about?

B: No, the article I read kind of was leaning towards&mdash;it just kind of formed and became a rogue planet and was coursing through...

S: In isolation?

B: In isolation; yes, in isolation. Was that&mdash;

SS: Well, I haven't heard that, but what I have heard and what is apparently true, based strictly on theory, mind you&mdash;no observations here&mdash;is for example, our solar system has nine, well, say eight planets now. But if you ask the theoreticians how many planets it originally had when it was born four and a half billion years ago, it was more like 30 or 40. And because these planets are, you know, sort of arbitrary trajectories at the beginning until they settle in, they have sort of fender benders; they don't actually hit but they get close. So when that happens one gets speeded up, the other gets slowed down. Most of them have gotten kicked out. So these are orphan planets, and that's a slightly different thing.

B: OK.

SS: But what Bob is saying here&mdash;so the majority of planets don't have a parent. Right? They're&mdash;I don't know if that's apparent to you. They're just wandering around and what Bob's saying is that some of them get captured again in a stellar cluster where you have a lot of suns that might have...

S: Yeah.

JR: But in a system like that why would all the planets be going the same way?

SS: Because the cloud that formed the star and the planets had a little bit of spin. It's very hard to have any, yeah&mdash;

JR: Oh yeah, I understand that but I'm talking about planets that are captured from some place else, and wander into the system.

B: It's actually a good point because that's one of the hallmarks of a captured rogue planet is, one would be an eccentric orbit, another one would be a planet that's like thousands of times farther away from the sun than say the Earth is. So it's really far away&mdash;

SS: Yes.

B: And the other one is that it could have a motion that's the opposite of the planets, so...

SS: Well, retrograde. Yeah, retrograde orbit. I mean, we don't see anything like that, but I mean, it's conceivable&mdash;

B: Well that's just it, they haven't really seen these.

SS: The problem is&mdash;the problem with capturing a planet&mdash;I don't know how many of you have tried to capture a planet. The problem... all right, two. The problem...

R: Is it like catching a dream or a rainbow?

SS: Yeah, it's a dream catcher. The problem is you've got to slow it down. And it's much more effective to slow it down by other planets that are moving in the same direction as the thing you're trying to capture.

B: OK. Plus, even to be captured, you've got to just happen to be moving in the same direction at a similar velocity. Very, very rare, right?

SS: Yeah.

B: But still the thing that really blew me away is that they're calculating that there could be hundreds of thousands more rogue planets than stars in the galaxy. Billions and billions of these rogue planets that they're talking about. That's huge.

S: Well, if a star, on average, is kicking out 20 or 30 planets before you're left with the stable orbits that remain... because that's essentially what's happening is that these planets that are in the stable orbits are the ones that survive for billions of years.

SS: Right.

S: If you're even in a slightly unstable orbit, you're going to be kicked out eventually.

SS: Or you're going to get swallowed.

S: You get swallowed up.

SS: I mean, a lot of planets get swallowed up.

B: Yeah, that's how planets are created; they just accrete, after all these collisions and they build up and build up. But yeah, some planets are getting kicked out just because they happen to be the wrong place at the wrong time.

S: Right. But this is all computer modeling, right?

B: Yeah.

SS: It is, it is. That isn't to say that it's wrong.

JR: But that would take more than 6000 years, and we know that, you know, that... that's the limit.

E: The magic number, yeah.

B: And that's the other thing is that they really&mdash;a lot of this is speculation and simulation and they haven't really found a lot of these&mdash;or any of these rogue planets. They can't really say, "that's definitely a rogue..."

SS: Think how hard it is to find one, though.

B: Right, right.

S: So we haven't found a rogue exoplanet yet.

B: They have some good candidates, but nothing definitive yet.

S: OK.

J: So let me get this straight. These planets start off in a solar system. There's too many planets so they get kicked out. So like these orphans, they lose their parents, and they're traveling on their own in the dark, and they become rogues. Right, so like, you know, it's a roguish planet.

SS: It depends on their behaviour.

J: It's like the Wild West.

R: I think you may be overly personifying these large masses just a little.

J: No but it all&mdash;it does follow a story. There is a story here.

R: Yeah, yeah, no.

J: So anyway, but this is pretty cool. Because first of all, I never even thought of a solar system having 20 or 30 planets. That's so cool; I never even imagined that. I just picture everything kind of like ours, but from what Seth was saying, it seems like solar systems are comfortable with a certain size, right? You know, you can't really have them be that big because it just doesn't work. So that's probably why the average solar system has a certain number of planets.

S: Yeah.

J: That's in the lower numbers than in the higher numbers.

S: I have a question for you, Seth. The idea was floating around about the mathematical relationship between the distances of the planets...

SS: Right, it's called.

S: Yeah, Bode's law?

SS: Bode's law.

S: Bode's law, yeah. So what's the modern thinking on that? Is that just an anomaly&mdash;a mathematical curiosity or is there something to it?

SS: Yeah, it was thought that there's a very simple relationship that gives you, in fact, the orbits of the planets. OK?

S: Right.

SS: And it was thought&mdash;well I mean, is this just numerology? In the old days of course, they thought that there was some kind of divine reason for this, and then it was considered only numerology. But I think that today, there's a more, if you will, subtle nuanced view of this, that in fact you just can't have an arbitrary planetary system and have it survive for very long periods of time. Because the planets are tugging on one another, and it isn't very much of a tug, but when you're talking billions of years, they mount up, so...

B: It's chaotic.

SS: Well, eventually, eventually. But maybe not in the lifetime of the Sun, for example. So the question is, yes, does Bode's law actually have some real physical basis and I wouldn't bet against it at this point.

S: So it's like there may be some gravitational reason why the planets sort of settle into these orbits, but we don't know what that is yet.

SS: It's like, you know, cannon balls. There are better ways to stack them than others.

S: Yeah, OK.

B: How about this: I was reading more about rogue planets and they were speculating about the possibility of these rogue planets having life and some sort of livable conditions based on heat generated by the planet, based on the radioactive decay can cause heat.

J: But there'd be no light and day... and yeah.

B: No, but there are potentially certain atmospheric conditions that could permit some hydrogen-based life, something. They were speculating about life on a planet with no star, which I thought was like, "wow, what an awesome idea."

J: That is cool.

R: On a rogue planet?

SS: Like Bob said, there could be. Because look, when you make a planet it's very hot, right? Most of you don't remember what the Earth was like four and a half billion years ago.

JR: I might do.

SS: If you read about it...

R: (laughs)

SS: ...yeah, Randi does. And it was hot, because all this stuff is slamming into the nascent Earth, the young Earth. And of course, all that energy gets converted into heat, so they're very hot. And you know, the Earth is covered with this crust which is a pretty good insulator, so it's a nice Thermos bottle. So the centre of the Earth&mdash;dig a hole in the Earth, 20 miles deep. You can do this this weekend. If you do, you'll find that at the bottom it's very very warm. And a lot of that heat&mdash;some of it is due to radioactive activity, but a lot of it is just left over from the birth of the Earth. So there's life, even on Earth, that doesn't depend on sunlight.

B: Well, chemosynthetic life like bacteria&mdash;

SS: Yeah, at the bottom of the ocean are these hydrothermal vents&mdash;

B: Oh yeah, they're awesome.

SS: So if it could be on the Earth, you could have life like that. I don't think you'd have Klingons living on a rogue planet. But you could have some kind of life.

R: You could have a. Remember Simply the furry lobster?

B: Or Europa.

S: Sniply?

E: Morlocks.

R: Yeah, Sniply.

Machine Monkey Interface (15:51)

 * Science Daily: New Brain-Machine Interface Moves a Paralyzed Hand: Technology Bypasses Spinal Cord and Delivers Signals from Brain Directly to Muscles

S: All right. We're going to move on to some monkey news.

R: Monkey news!

J: Monkey!

E: Monkey!

J: Monkey man.

E: Ooh ah ah.

S: Um, it's only sort of monkey news. It's also brain/machine interface news.

B: Again?

S: Again, yeah. But this is a little different.

B: All right.

S: It's slightly different.

B: Did they make any improvements yet? Like, come on!

S: OK, this is what they did. Some researchers took some nice, innocent monkeys and they paralysed them.

R: No!

S: But it was only temporary.

B: Why wouldn't they paralyse the mean monkeys?

S: It was only temporary. They injected something into their spinal cord so they couldn't move their limbs.

J: And then they tickled them.

S: It's temporary.

(laughter)

E: Are you crying, Rebecca? Oh my gosh.

R: I'm just thinking of the poor little paralysed monkeys.

S: No, but they're all&mdash;so listen&mdash;

E: Stop thinking about them.

R: Think about the news item from the other week where they were teaching them to read.

(laughter)

J: Rebecca, it's even worse: they let birds attack them.

R: No.

S: (laughs) They let the birds&mdash;that's right, peck on the paralysed monkeys.

(laughter)

S: So... they put in a computer chip, a brain/machine interface, and they connect the electrodes directly to the muscles in the monkey's hand. So what they first did, though, was that they would like have the monkey pick something up and go through some tasks they taught it to do&mdash;

R: And then slap itself. Stop hitting yourself! Stop hitting yourself!

E: Stop hitting yourself. Why are you hitting yourself?

(laughter)

S: Before they did the brain/machine interface, they essentially taught a computer what signals, what muscles the monkey was using to do a task, so that the computer knew the pattern of muscle contractions. Then they paralysed the monkey and then they connected a computer chip with the algorithm in there to&mdash;directly to the muscles&mdash;they completely bypassed the spinal cord. And then the monkey was able to control the muscles directly from&mdash;you know, so basically the chip would interpret the brain signals&mdash;knew what they meant because it had already learned what the brain signals correlate to, with the muscle movements. And so the monkeys were able to do almost as well, almost as well, control the hand.

B: Almost as well? Wow.

S: With&mdash;completely bypassing the spinal cord&mdash;just direct brain-to-muscle connection.

B: That's huge.

S: Yeah, it's nice. See, you thought it was the same old thing.

B: Well, that's what you led me to believe.

S: Well yeah. I have to give you something exciting, you know.

B: OK, thank you.

S: So, I mean, obviously the&mdash;

B: That is cool.

S: &mdash;obvious application here is you have a paralysed person; you could have them control their muscles directly even if their spinal cord is severed or whatever. So this research has been ongoing and this is one more step. We always do the cool stuff with monkeys because you could actually implant stuff in their brains. With people we're trying to avoid doing that, so they get the brain caps, which don't work as well as implanting stuff in their brains.

J: Yeah, you know it's so weird. I feel bad because it's monkeys but if they do it on people it doesn't bother me. Is that weird?

S: Yeah, you're weird.

E: Yes, yeah, you're a freak.

B: Yeah, you're... cold.

J: No, no no! Because people at least can say, "yeah, do it to me."

S: They can consent. Yeah.

J: Yeah. They monkeys, the poor guys. You know.

S: But the thing is, it was just temporary; they didn't permanently paralyse them.

E: No, no.

B: How transferable, though, are those algorithms? Do they have to read you first before you're paralysed?

S: Yes.

J: Oh, it's unique to each person?

B: That kind of stinks.

S: Well, yeah, well yeah yeah, so yes. Yes, that's correct.

J: So it's not going to work.

S: No, that's not true, Jay, because you could train it.

J: No, because if you're paralysed, we're going to help a paralysed person...

S: Because, they tell... imagine yourself doing what you wanted to do.

J: Oh OK, OK.

S: Your brain will still activate in the same way. It's just like if you imagine yourself doing something and you actually do it, the pattern of the brain activation is actually quite similar.

J: So what if you think like you're flying&mdash;

B: Like if you're lucid dreaming, Jay. It's a similar thing with lucid dreaming.

R: Well, no like batting...

S: Yeah.

B: Visualisation.

R: You know, like you can improve, like if you're a baseball player&mdash;yeah, if you visualise it, it helps your muscle memory. It's kind of like , only real.

E: It works, you know.

(laughter)

SS: I mean, even aside from the prosthetic use&mdash;I was talking to some guy who works on brain/machine interfaces and ask him how long before all of us can surf the web by just thinking about it instead of...

S: Right.

B: What'd he say; what'd he say?

SS: He said ten years.

J: Oh.

E: Wow.

SS: Well, that's what he said.

E: Bob, you might still be alive.

B: That means thirty years. I'm going to still be alive.

S: Yeah, ten years. That's kind of that magical number of&mdash;

SS: Everything is ten years away.

S: &mdash;ten years means that we have no idea.

R: Long enough for you to forget that I said ten years.

S: Right.

(laughter)

S: It's either ten years or one funding cycle, whatever that is.

R: Or one&mdash;like, however long the researcher has to live.

(laughter)

J: I mean, I actually think five years is the most common.

S: Five years is common.

B: Five years is common.

S: It depends on what your funding cycle is, but five years is common. Ten years, to me, means we're not really sure. But, I mean, that's not an unreasonable estimate, actually, from my reading of the literature.

B: But it's going to happen, right? It's going to happen.

E: Yes, don't worry, Bob; it will happen. Calm down; have a cookie.

B: I know it, I know it's going to happen.

R: Don't worry; you're going to get your robotic monkey arm, all right? Just calm down.

(laughter)

B: I can't wait.

S: It could easily be twenty years, though.

JR: Does everybody know is?

SS: Yes.

R: Yeah.

JR: The guy that made the.

SS: Yes.

S: Yeah.

JR: Oh, OK. Quite some time ago&mdash;two and a half, maybe three years ago, I had a conversation with him. He was talking about this artificial arm they had built for this amputee who had a stump. It's an astonishing thing. And he was able to slip this arm onto the fellah and with sensors&mdash;no connections, no injections or poking wires inside the body at all, but just by conductive patches on the fellah's arm, he was able to move the arm and pick up a glass. The first glass wasn't a great success; it went (makes cracking sound), it fell right out of the air, but eventually he got to control this thing. In other words, the connection to the nerves in the guy's system were made just from patches stuck on the skin, on the outside.

S: Yeah, that technology is 15 years old, I mean...

J: Yeah, oh yeah.

S: If I remember&mdash;

B: I've seen it connected&mdash;

S: But I've seen a guy walk with that; you know, like...

B: &mdash;to the chest muscles. It's bizarre.

JR: Oh really?

S: With surface electrodes attached to the leg muscles and he can activate them in sequence in order to walk. But you know, it takes a lot of training and only the people who really do the best could actually walk with any kind of efficiency, and even then it's really energy-intensive and very awkward. You could only get so much precision with the surface electrodes. That's why I was saying, with people, they tend not to do the implantable stuff. With the monkeys we can implant stuff and we can get much more precision&mdash;

J: I like how Steve's showing like sawing...

(laughter)

S: But it's also just tough long-term&mdash;it's not a good long-term solution to have anything foreign sticking inside your body because then it's just a pathway for germs. So it's problematic. It's OK if you're doing it on a short-term experiment, but not as a long-term solution. That's why you have to&mdash;then you go with surface electrodes or surface EEG readers, but they just don't have the precision that the implantable stuff does.

JR: But they must have some sort of... other sort of thing&mdash;interface&mdash;I'm looking for the term. Interface with the nerves and the machine on the outside that are not just patches. Somehow I have a feeling that there should be some other interface.

S: Yeah.

J: Weren't they doing muscle&mdash;they were reading, like, muscle tensing too, as a way to take commands?

B: I've seen attachments like to the chest muscle, and he would flex the muscle, and by flexing your chest muscle it would, say, contract the fingers. It looked so weird though because he's contracting his chest and his hand is moving and it's...

S: It was just a way of activating those muscles, yeah.

B: Yeah, and it became a reflex for him. That became how he did it and he didn't even think about it any more.

S: Right, because of brain plasticity, it'll learn how to do whatever. OK.

Finding ET with Robots (23:31)

 * Science Daily: Finding ET May Require Giant Robotic Leap

S: Seth, this next item&mdash;I don't know if you've actually seen this item but it's in your speciality. This is an article about using robots to find ET. Did you come across this recently?

SS: This may be a cost-cutting move at my institute; I don't know.

JR: Your job is hanging by a thread, in other words.

SS: Nothing new.

(laughter)

S: So this is based upon arguments put forward by John D Mathews. Do you know who that is?

SS: Uh, John Mathews, no.

S: OK, professor electrical engineering. He wrote an article in the current issue of the journal of the British Interplanetary Society, and he's essentially arguing&mdash;actually, similar to an argument that you made during your talk today at NECSS that probably the best way to find ET, he argued, is to build exobots, self-replicating robots that we could just send out into the galaxy and that would propagate through the galaxy and explore it that way.

B: Well did that a half a century ago.

S: I know; it's not exactly a new idea.

B: Whatever, OK go ahead.

E: But that was a long time ago, Bob.

J: Steve, are they going to sound like the robot that shot at Chewbacca in the second Star Wars movie?

S: That would be cool...

B: That little guy on the Death Star?

J: No, the black one that found them on Hoth.

E: Nooo, Hoth, yeah.

J: Ming ming a ming mat, ming man a ming. Remember that thing?

S: Yeah, of course.

J: Thank you, whoever did that.

R: What?

J: You don't watch Star Wars, do you?

R: I've seen Star Wars.

(laughter)

E: The original ones?

R: Yeah.

E: OK.

R: I know the noise that the... um, thing makes.

J: R2D2? Yeah.

R: Oooooaaaah, like that. I don't know, whatever that other thing was.

J: What was that?

R: That was my Chewbacca impression.

J: Oh my...

(laughter)

R: Oooooaaaah! (laughs)

SS: I always wondered about Chewbacca... would you really want another primate as your copilot? That doesn't seem right.

E: Yeah.

J: I saw the original Patterson picture of the Bigfoot, and they put Chewbacca's bandoleer on it.

B: That was awesome.

E: Oh yeah, that's right, they did.

SS: But I'm not quite sure&mdash;sending them out into the galaxy; I'm not quite sure what that means unless you have particular targets in mind.

S: Yeah.

E: Yes.

SS: I mean, you could send it to Mars; you could even send it to the Moon; I mean, you remember 2001; there is this big monolith on the Moon. Not very informative but clearly artificial. And we haven't looked at the Moon for monoliths. So you could just send a whole bunch of robots, not self-replicating ones. I don't think you ever want self-replicating robots; that's a dangerous thing.

R: Then you get.

B: I think that was part of&mdash;how do you pronounce his name&mdash;is it von Neumann?

SS: Von Neumann.

B: Von Neumann architecture, was that they were self-replicating and that they would go out, they would mine resources on the planets, replicate duplicates of themselves, send them out. But the problem is, that's actually an argument for why there are no ETs because people say, "well, where are these machines that other civilisations&mdash;" They're not...

S: If they existed they would be here already.

SS: Yeah, you would see them chewing up the universe, yeah.

B: It's funny how that's an argument against ET in that we're&mdash;

SS: But on the other hand, you could think of, we have von Neumann machines on the Earth. They're called insects. And they reproduce like crazy, and they eat stuff, and they eat stuff. And yet, they don't eat the whole world because, in their case, they're competitors.

B: It's a balance, yeah.

SS: They hit an equilibrium.

R: So we just need to send out some bigger robots.

SS: But the thing is, is everybody doing that? I mean, it kind of applies. What Bob is saying here is actually a good point. The fact that we don't see the universe being eaten up by von Neumann machines must mean one of two things.

B: It's kind of disappointing.

SS: Well, you can look at it that way.

E: Good way of looking at it, Bob.

B: No ETs!

SS: I mean it may be that there is a galactic injunction against building these things and if you build some, the hand of aliens comes down and...

B: or something.

SS: Something like that. Either that, or it's impossible to build them. There's got to be some reason for this, actually.

B: It's impossible; it's just&mdash;

S: When you think about it, it seems almost inevitable that the universe would be taken over by super-powerful, advanced mechanical, artificial life.

B: Maybe it is; we're just not seeing it yet.

E: It just hasn't hit us yet.

S: True, I mean it's...

B: It's on it's way, approaching us at the speed of light and we're just like...

SS: There's a big wave of von Neumann bugs heading this way.

S: It takes just one civilisation to create Cylons and we're F'ed, right?

SS: That's right.

R: Mmhmm.

S: Right?

B: Damn.

S: Isn't that inevitable?

J: That is so creepy.

S: Why isn't the universe taken over by Cylons?

(silence)

R: You should write a paper.

S: I'm asking.

SS: If I know, I'd be in Stockholm now, collecting my prize. That's all I can say.

S: You'll invite me, though, right? When you do?

B: Wow, now I'm really thinking about this.

J: All right, next topic.

S: Wait wait, I'm not...

B: No! Come on; this is cool; let's keep going.

S: This is what keeps me up at night.

B: He could always cut it.

S: Why isn't the universe taken over by Cylons?

SS: This is just a modification of what's called the. And a lot of listeners will know about the Fermi paradox. If the universe has spawned all of these civilisations, some of them might be interested in colonisation. So why don't we see artefacts of colonisation everywhere? Why aren't the aliens everywhere? And that's what said at a bad lunch in 1950.

S: Yeah.

SS: So, this is just a variation of that, by saying, "look, forget about little soft squishy aliens trying to conquer the galaxy", that the machines will do it, and they can do it, as opposed to biology, which would have a very hard time. And so, that's all that Bob is saying, that they should be everywhere. We don't see evidence of them. And it could be that, as you suggest, Bob, that the real problem is just that we're not very good at seeing the evidence.

S: How about this: are we just saved by the fact that the universe is really fracking big?

E: And expanding.

S: And everything is really far away. And that even if a million years ago, a civilisation spawned some of these von Neumann machines, would they have had enough time by now to get everywhere? Or is it just that space is just too big?

SS: Well, a million years is not enough, but a billion years is. They could be everywhere in the galaxy in a billion years without having to do anything very, very difficult.

S: Has someone done that calculation?

SS: Or at least, you know... yeah. The galaxy's been around for 12 billion years. That's plenty of time.

JR: Isn't there a basic assumption here that we're making, because we're terrestrials and we would want to go out there and look, that all of these other critters would want to go out there and look too?

S: If only one would...

SS: Maybe most of them are just not interested in that.

JR: Yes, exactly.

SS: I mean, if you walked around the streets of Spain in 1491 and say, "hey, would you like to get on this wooden ship; you know, die of scurvy, cross the Atlantic looking for stuff?"

B: Screw that.

SS: And nine out of ten, ninety-nine out of a hundred, nine hundred and ninety-nine out of a thousand say, "no thanks, I'm happy selling shoes on the streets of Barcelona."

JR: Yeah, yeah, yeah.

SS: But the fact that a few people were willing to do it was all that was necessary. So it's the same argument. Most of them are not interested in colonisation, that could be. But it doesn't take many to change the picture.

J: Guys, what if those machines...

B: If it's synthetic life&mdash;digital life. They wouldn't care. Just put on pause for a few millennia.

SS: Yeah, just play a lot of Freecell...

B: Right; they wouldn't care.

J: What if those machines that they sent out were bacteria?

R: Well yeah, that's what I was thinking. I find it odd that we would think of it in terms of&mdash;well yeah, of course they would do machines, but even in our current science news a lot of what we're talking about is how to create organic life, and how to genetically modify organic life. So why wouldn't a highly advanced alien species come up with an organic sort of thing?

B: It's semantic. I think once you read a certain level of technological sophistication, what we call machinery or even biology.

JR: Yeah, yeah.

R: Any sufficiently advanced, etc...

B: It's going to be a joke, it's going to be a joke.

J: But Steve's asked asked a very serious question, and it's a really provocative question, and I'm saying it could be bacteria. What if the machines existed a billion years ago and this is&mdash;we're an iteration of an alien species, advanced, super-advanced technology.

B: Why send bacteria?

SS: Yeah, but Jay this idea has been floated a lot, so to speak. I mean, it's called. It's never pan-eggia; it's some kind of sex-bias there, but any case, panspermia. And it works. If you want to seed the solar system from Mars, for example, could we be Martians? That works, you can put a microbe into a rock on Mars, kick it off, the rock. Have it land on the Earth four billion years ago and we're the descendants of that. That's conceivable. But if you talk about putting a microbe, even the toughest microbes that we know about, put them in a rock, kick them off and send them to, you know, a star 20 light-years away. They're dead by the time they get there. It seems they're all dead.

B: Even the ones, like the, extremophiles that could survive&mdash;

SS: I'm told by the astrobiologists, even the toughest microbes can't take it because there's the desiccation, no liquid water. And the other thing is there's very harsh radiation environment in interstellar space. And so it just breaks you apart and even radiodurans can't fix it without water.

B: They're amazing, though. You blow apart most of their DNA and they're like, "that's OK, I could deal with this" and they just kind of like bring it back together and they're cool with it, but even they can't take that.

J: So, should we assume that something that we consider synthetic&mdash;not bacterial but synthetic&mdash;it would survive in space easier than what we think, that we know to be bacteria? Like, so if we made nano-machines&mdash;we don't know what they'd be made out of today.

B: Just create a little mini-magnetosphere around your ship and deflect the cosmic rays and whatever, and then... I mean, right? How much?

SS: It takes a big magnetic field, you need&mdash;

B: Sure, but hey, we're talking aliens, they could do a lot of shit&mdash;

SS: Yeah, well aliens could probably do it.

(laughter)

SS: But maybe what you do is you just send golf balls into space. You put the machines in there. If they're really good, you know. Look, as said, there's a lot of room at the bottom.

B: Yes.

SS: You can make lots and lots of things that are small. Because there's plenty of room between the size of you and the size of an atom. A lot more than between the size of you and the size, say, of the Earth. A lot more room. So, you know, we're already building machines out of individual atoms and molecules and things like that. I mean, they're very simple things, but a hundred years now, you could build a machine&mdash;

B: Right, well, we're made of nano-machines.

SS: Yeah, but I'm not talking biology. I'm talking about stuff that looks like miniature cars or whatever.

B: No, yeah, yeah. Absolutely.

SS: So if you can do that, if they're clever enough that they can make more of themselves from whatever they find, which biology might not be able to do. I mean, biology is contingent upon having the right kind of stuff.

B: Very limited environmental...

J: So, to answer my question, from what you are saying, it sounds like it's kind of a yes. That...

B: What was your question?

J: We could build something...

SS: We could answer yes, anyhow.

J: ...that's a lot hardier than bacteria.

B: Shit, yeah.

J: That could survive...

B: Bacteria are awesome, but sure, yeah.

JR: When I see these extremophiles living in boiling sulphuric acid, huge pressures and temperatures and such, so far beyond what we think of NTP, normal temperature and pressure, I'm astonished&mdash;they must&mdash;there must be other extremes of that too where we just can't even imagine. I can almost imagine boiling sulphuric acid as being a nice, warm comfy place to be. And that pressure, oh the pressure is so good today!

J: (laughs)

JR: But I'm afraid that there might be degrees well beyond that that I just can't comprehend.

SS: Well, I mean, take a look at the Moon; we haven't found any life there. That's a situation where...

JR: We haven't found...

SS: Yeah, well there probably isn't any.

JR: ...a little deeper

E: Dinosaur DNA.

B: What about Europa?

SS: I'll buy you lunch if there's life on the Moon.

R: Yeah, space dinosaurs. Let's not forget about space dinosaurs.

E: Can't forget about them.

JR: Oh, the space dinosaurs. Always, of course.

God Spot in the Brain (34:24)

 * Huffington Post: No 'God Spot' In Brain, Spirituality Linked To Right Parietal Lobe

S: Well, Rebecca, tell us if scientists have found God in the brain.

R: Nope.

E: Next!

S: OK, now...

(laughter)

JR: Next question!

E: I could have told you that.

R: Yeah...

S: A little more detail please.

R: Aw, fine. It's late, Steve.

B: All right, hell no.

(laughter)

R: We've talked about this topic before on the show, the idea of a god spot in the brain.

E: G-spot.

R: Yeah, thank you, Evan.

E: You're welcome.

B: Did he steal your joke too?

R: No, I would never make that joke.

B: OK.

J: (laughs)

B: Just checking.

R: You can have it. Yeah, the idea is that there's one particular spot in your brain that is responsible for belief in God.

S: It's called the cortex.

R: (laughs) It's called the entire brain.

JR: Now this is an evolved spot, is it?

R: That's the idea.

S: No, it's created.

(laughter)

R: It depends how big your God spot is. Well, there was recently a study that apparently found that there was no God spot in the brain and that spirituality is linked to the right parietal lobe. And so this is an interesting study; there have been other studies in the past like I mentioned.

J: Where is the right parietal lobe?

R: It's this side.

E: On the left side of the...

(laughter)

R: It's like right above your ear, yeah.

J: Above your ear.

E: God spot, come on.

B: Steve, how does this relate&mdash;I've heard that there are people that have seizures, certain seizures in certain parts of the brain that gives them this God-like experience. It's like, "oh my God; I'm in the presence of God because..."

J: (laughs)

B: Yeah, I'm not lying.

R: It's called an orgasm.

(laughter)

B: No, no.

E: Oh, God; oh, God!

J: That's like, Bob, you're going to die and and you're going to see God and you'll go, "God damn!"

(laughter)

B: No, some people have seizures; it gives them&mdash;their body shakes but other people have a seizure in a part of the brain that gives them like this God-like epiphany.

J: They have a religious experience. Yeah, we know about that research.

B: Right, because it's the location that the seizure takes place.

R: Yes, this is Steve's profession but I just want to mention, before Steve launches into a full explanation that like a lot of studies on the brain, this study in particular involves people who have had damage to one specific part of their brain that these researchers were checking to see if that's where the God spot is. So people with brain damage are very useful to brain scientists because it allows you to isolate certain part of the brain and figure out...

B: Where's the damage and what's missing?

J: All right; so what's the answer here?

S: Well, what Bob was referring to&mdash;so yeah, what those people experience is a profound connection to the universe and that gets culturally interpreted as whatever your religious belief is. So, you're a Hindu, you have a profound Hindu experience, right? If you're a Christian, you have a profound Christian experience, but the core experience is feeling that you're connected to the universe.

E: What if you're an atheist?

S: You still feel that, but you just feel a profound connection to the universe rather than&mdash;

Audience: You turn into Carl Sagan?

S: &mdash;and you don't personify that as a deity.

E: You can't call it a God spot.

J: Somebody in the audience said you're...

Audience: You turn into Carl Sagan.

J: &mdash;thank you; it was DJ.

S: But here's the thing: the reason why you experience that is because that's the part of the brain that makes you feel separate from the universe. So when you turn off that part of the brain, that separation is what goes away. But the separation is what's actively neurologically happening.

J: Are you saying spatially or emotionally? Like, I'm not...

S: So your whole reality is constructed by your brain. Everything that you&mdash;you know, your whole concept of yourself and your universe and that you're in your body and your body is separate from the universe but in the universe. These are all constructs in the brain. One thing your brain constructs is that at some point you end and the rest of the universe begins. Now you take that away and what are you going to feel? That you are one with the universe.

JR: Like a Republican.

(laughter)

S: That's a very profound experience.

J: Yeah, but when you say that, I just think like you just feel like you're one big blob.

S: Sometimes.

J: Like you're the chair; you're the walls; all of that.

E: No boundaries.

S: You might feel like you physically become huge.

J: Like are you having sensation from something far away?

S: No, it's not anything as concrete as that, but it's just... So anyway, so people will interpret this sensation&mdash;again, whatever their religious belief is or cultural belief, so they may experience that as being in the presence of God. But it really is just a breakdown in their mental construct of reality.

B: I hate when that happens.

J: Yeah, OK.

E: I love it.

S: People pay a lot of money for drugs to make that happen.

E: Well, there you go.

R: I'm on some of them right now. Let me tell you it's beautiful. I love you all.

(laughter)

J: Rebecca, can you feel my ass?

B: Does that mean you love yourself?

R: Right now? Almost like I'm there.

(laughter)

S: Is that a question or a request?

(laughter)

R: So this study in particular looked at people who had brain damage to the right parietal lobe. It specifically looked at 20 people, which isn't a lot but from what I understand in studies like this they tend to be fairly small.

S: It's hard to find a lot of people with specific brain damage.

R: Yeah, but also&mdash;and this is one of the flaws I think in this study is that there's no control. So everybody in the study has the damage. And what they claim to have found is that&mdash;they surveyed the participants asking them about spirituality, general spirituality topics and how close they felt to a higher power. And what the researchers claim to have found is that people with more damage to the right parietal lobe claim to have more connection to a higher power. So now I'm going to read you a quote from one of the researchers though, that really... it made my skeptic alarm go off, that&mdash;it made me think that maybe the conclusions the researchers draw might not necessarily be valid based on the evidence. So you can decide for yourself.

"Neuropsychology researchers consistently have shown that impairment on the right side of the brain decreases one's focus on the self. Since our research shows that people with this impairment are more spiritual, this suggests spiritual experiences are associated with a decreased focus on the self. This is consistent with many religious texts that suggest people should concentrate on the well-being of others rather than on themselves."

Does that&mdash;is it just me or does that sound sketchy?

S: It's a little sketchy, but also it's... even if that's one factor, there's probably a dozen other factors that also contribute to religiosity that have nothing to do with that. It's too complicated a phenomenon to say it's due to a decreased focus on the self.

R: And I know a lot of atheists who don't&mdash;who do focus on the well-being of others. Is that some artificial&mdash;you know, are they outliers? I don't...

S: Then it depends on how do you define spirituality? Maybe they're humanists who tend to be spiritual in a non-religious sense. It's way too complicated to boil down to that.

R: It's messy.

S: Yeah, it's messy.

R: Yeah, as says, I think you'll find it's a bit more complicated than that.

S: Yeah, and you've got to put this into the context of other research that showed that there are definitely parts of the brain that correlate with religious experiences or profound experiences or spiritual. Again, it's always hard to interpret that because it's always being filtered through the specific cultural manifestation of underlying neurological processes that are all interacting with each other in very complicated ways. And it's like that earlier article that showed that there is a God spot; like, an opposite conclusion but basically the same data. And they had a map of the brain showing where the God spot is and it was like 90% of the cortex.

E: (laughs)

S: It's like the frontal lobes, the temporal lobes, yeah it's everything. Except for the parts of the brain that are, like, your motor cortex and your visual cortex. OK, every thinking part of your brain is involved in some way to your religious experience. Yeah, because it's such a very complicated phenomenon.

J: So would you say that it's just all over the place; it all depends on who you are, number one? Or...

S: It's not a localisable, specific phenomenon, neurologically.

B: It's a brain phenomenon.

E: It's not a spot, that's for sure.

S: There is no spot. I mean, yeah, the term "spot" is such a misnomer. You know, it's like saying what's the part of your brain that's involved in, you know, in love. You know, well, there is no one part of your brain; it's a complicated phenomenon that's going to involve lots of your brain.

B: Maybe the part of your DNA?

R: It reminds me of the search for the gene for blah blah blah. You know, in popular media. It's like, "oh, there's a gene for this..."

S: Yeah, like the gay gene.

R: But it's never that s... the gay gene, yeah. Right.

S: There's not going to be a God spot. Yeah, it doesn't fit.

JR: Well what kind of damage are we talking about here? Physical damage to that area of the brain or disconnect?

R: I think it's usually strokes, I think.

S: Mostly, or statistically, yeah.

R: Or collisions to the head, because yeah, it's right there, so it's hit-able.

SETI Update (43:37)
with SETI senior astronomer Seth Shostak

S: Well, Seth, while we've got you here, get us up to date on how SETI is doing. I know you guys had some funding problems earlier; has that sort of settled down a little bit?

SS: Well, it has a bit, Steven. About a year ago, our partner with the Allen Telescope Array, which is the instrument that we use for our studies up in northern California&mdash;the University of California at Berkeley&mdash;lost most of their funding and consequently they had to withdraw from the project. So suddenly we had to find the money not only to do the science but also to maintain and run the array. And we have found another partner, SRI, they're working with the Air Force. So they use the array part of the time for mapping space junk and stuff like that. We also went out and we had a fund-raising campaign where we just asked the public, hey look, you know if you like this program, send some money. So we raised some money that way. So we're back on the air. The instrument which had been shut down on tax day in 2011 is observing as we sit here. And we also have all these planets being discovered by NASA's &mdash;several thousand, you know there are several thousand candidates&mdash;not all of them will turn out to be planets but probably 90% of them will be. So we're looking at those, because at least those are star systems, again, where we know that there are some worlds.

S: So funding, just to break it up into categories, a few of the possible sources. One is that you partner with other people and you share the array with them.

SS: Yes.

S: So that you can just cover costs. Two would be just, like Allen, just billionaire&mdash;

SS: Somebody just writing you a cheque.

S: Benefactors, yeah. And then, just going to the people, just going to the, you know crowd-sourcing the money, I guess. What do you think about the idea of shifting more towards, just like, micro-donations from millions people, that kind of funding, with social networking and the Internet and whatnot. Is that something you guys are looking into?

SS: I hope that we are. I think we should be because... you know, I think a lot of people&mdash;I've often been of the opinion that if your form 1040, if your tax form had a little check box at the end, "would you like to lower, you know, your refund by one dollar, by giving one dollar to the Search for Extraterrestrial Intelligence"; if 10% of the population did that, well, we'd have&mdash;I mean, there'd be plenty of SETI research being done.

S: Right.

B: Yeah, but how many check boxes would be on that form?

SS: Well, that's the problem. And in fact&mdash;but you know the NASA SETI program&mdash;it was a NASA program when I joined the SETI institute&mdash;that was killed in 1993 by a congressman who was trying to prove to his constituency that he was saving the taxpayers money. And I remember driving home, my next-door neighbour was washing his car and he'd read the headlines that NASA SETI had been canceled and he said, "well, Seth, I guess you've lost your job, but at least I'm saving three cents per year", which is what it was costing him.

S: Right.

SS: So he was saving three cents per year. He went out and bought a BMW the next week. So... yeah. That check box wouldn't have to be dollar&mdash;if it were a dime and enough people checked it.

S: All right; well, definitely keep us updated. I mean, SETI is something that I believe very&mdash;you know, firmly in. I definitely think it's worth the amount of money that we're spending on it. I think... you know, so...

SS: I hope it's worth more than that, Steve.

(laughter)

S: Well yeah, you know I&mdash;it should be worth a lot more.

SS: Let me just say something in that regard. The whole idea was cooked up more than 50 years ago.

S: Yeah.

SS: You know, point antennas toward the sky. And then we only had guesses about whether the stars had planets, or how many planets there were, or if any of them might have life and that sort of thing. And we've learned something about some of the questions that were formulated a half-century ago. And they've all come up thumbs up in the sense that they're all pointing to the idea that our situation here on Earth is nothing special. We're not special. And it could have gone the other way. There could have been show-stoppers. It could have been that planets were rare or that kind of thing. And none of that has turned out to be the case. Every time you learn something new about the universe, it seems even more attractive for life. So, you know, from that point of view, it's like being on a desert island; you begin to see boot prints from pirates.

E: Arrr.

S: Do you think that public interest...

R: Do you want to meet the pirates, though?

E: Space pirates!

(laughter)

SS: I don't know; they might have some good grub.

S: Do you think public interest is increasing because of all the exoplanets that are being discovered?

SS: Well, that's hard to say. Probably it is. I mean it's very difficult to judge what excites the public about this sort of work. The only real bump in interest from the media that I ever saw was when  was popular.

S: Is that right?

SS: Yeah.

J: Well, maybe when comes out with the Cosmos series, that will inspire people to get more involved.

B: That's a good idea.

E: Let's hope, let's hope.

B: It could.

S: When is that coming out?

J: Isn't it this fall?

E: No, 2013. About a year from now.

J: Oh, OK.

S: About a year?

R: The audience thinks it's 2014.

E: Is it 2014?

R: They sound really sure of themselves.

E: Oh, they pushed it. I heard originally 2013, but I'm not surprised.

S: Wow, it's a long time. All right.

E: They're doing a good job, I'm sure.

The Coming Singularity (48:26)
Should we, and how can we, hasten the coming the singularity?

S: Well, before we go on to science or fiction, we're going to take some questions from our live studio audience.

JD: Hi, my name is Jared Dickman.

R&E: Hi Jared!

JD: So I had this whole spiel worked out about what I wanted to say to you guys and let me just start off with "hi".

R: It's a good start.

JD: You mentioned some guy who had been listening since he was 14 and that's nothing. I have been listening for six and a half years, since I was around 12 years old.

R: My god.

JD: Yeah, right? And I didn't have a great...

R: Get out!

(laughter)

JD: I didn't have the best family life growing up, which is, you know, whatever. What I did have every week was you guys.

R: Aww.

JD: Talking to me about what I did want to hear and I just wanted to say, I love you guys.

R: You can stay. You can stay.

(applause)

JD: Thank you so much for everything that you do and keep doing it because it is making a difference.

R: Awww.

E: Thank you. Wow.

B: Wait, you can't even legally drink, can you?

JD: Nope. That being said, what I do want to do is... I want to change the world. And I want to do that with the tools that you guys have given me, of science and critical thinking.

S: Whoa, whoa, wait, whoa, wait. You want to say that, you've got to say it the right way.

JD: I want to change the world!

(laughter)

S: Now I believe you. Go ahead.

E: For good or for evil?

JD: I'll let that part out later... (inaudible) But how I want to do it, and no thanks to Bob of all people, I'm currently studying computer engineering and physics. I want to go on to quantum computing or quantum engineering or something like that, and just go crazy with that and see what that has to offer.

B: Awesome.

JD: So my question for you guys is this. The, you know, imminent in my humble opinion, is arguably the end game for humanity. You know, that's what we've been working towards; that's what it is. What do you think the most important or maybe most three important scientific fields are for getting us there as quickly as possible.

S: Um.

B: Artificial intelligence, that's key. I mean, there's classics. Artificial intelligence, there's genetic engineering and there's&mdash;

S: Nanotechnology.

E: Nanotechnology.

B: Nanotechnology. Those three are like.., and they can all enhance each other.

E: The holy trinity.

B: If you... yeah right. I mean if you've got mature nanotechnology, it just helps with so many other fields, but...

S: I would say...

B: But AI&mdash;the classic definition, I think, of the singularity is AI. Because then you've got a human-level intelligence, and once you reach that, then you just make it a little faster and that's super-human. So that's one of the ways. There's lots of ways to define the singularity. Being unable to predict what this thing is going to do is a key aspect of it. So once we have AI then that's the singularity, in my mind.

JD: Yeah. Somebody was arguing to me to actually stop studying quantum computing and go into artificial intelligence hard-core. Because once you can beat the, that's it. And then we could just have a computer build a smarter computer and cascade.

S: The Turing test is not the be-all and end-all of artificial intelligence, for a lot of reasons.

B: It'd be impressive, but...

JD: And I was trying to counter-argue that, and I couldn't think of any great reasons as to why we need anything...

SS: Jared, what I want to know is why do you want to hurry up the singularity? I mean, why do you want this to happen? I mean, you lose control of the planet. Is there some reason you want to lose control? That's one way to change the world; I mean, I agree with you.

R: Well, he already said he identifies with Bob, who we've already established is a sociopath, so...

(laughter)

B: Sociopath?

E: No, he's just afraid of dying.

J: But Seth, your statement implies that we have control now, and I don't really...

SS: Well, I mean from the dogs' point of view, we do.

(laughter)

E: Yeah, right?

SS: Yeah, we have control. But I mean, the singularity is where, in fact, all this rapid improvement in the ability of machines suddenly&mdash;it's becoming&mdash;I mean, it's exponential and then it reaches a point where it just trumps everything that we do. Now, why is it that you look forward to this?

JD: Well, what I think is going to happen and I could be totally wrong of course here, but I think that humans and robots are going to merge as the singularity comes closer and it's not going to be Homo sapiens and robots, it's going to be Homo robotica and we are going to move forward and expand out from there...

SS: You know, I'd like to think you're right, but what will happen between now and then of course, is we'll be doing things like putting chips in your brain and all that sort of thing.

JR: Who's going to be working for who, that's what I want to know.

SS: Yeah, exactly.

B: Who's signing our cheque?

SS: And the point is that you can do that, but to me that's like putting a four-cylinder engine in a horse. You get a faster horse for a while, but eventually you decide the heck with the horse part, we'll just build the Maserati.

S: But the difference is...

SS: But the idea that we're going to be simpatico with the machines; I mean, it's like, don't worry dinos, we might get wiped out but we're going to merge with the mammals.

B: (laughs) That's a great analogy.

S: But the difference though Seth, though, is that&mdash;you're right, a horse and a car, why merge them; just build the car. But that's because those are both tools for us. But we're the people that we're trying to merge with the machines. I do think that changes the nature of the game a little bit because when we can be as&mdash;whatever, as smart as our artificial intelligences because we have mature brain/machine interface, I think, first of all, it will make us more willing to embrace that technology if it's us and not just tools that we're building. And it also changes&mdash;you know, it has the potential to change our potential in terms of what we can do and how long we can live and all of these kinds of things. I don't know; that's just another wrinkle in all of this, because it's changing humanity.

B: All right, but don't forget though...

S: Different than just improving our own tools.

B: But machine intelligence evolves differently than biological/cyborg intelligence. You've got a very small window there. I mean, the machine intelligence can evolve so much quicker and faster than we could upgrading ourselves and that's a big difference.

S: What if we become the machine intelligence? I mean, just imagine&mdash;

B: I think that's key; we might need to make sure that happens.

S: Having, for all intents and purposes, an AI but that's designed to be a symbiotic relationship with your own brain so that it is you, but it's interfacing with your brain because you're your brain too.

JR: But who makes the contract?

S: Right.

J: Yeah.

JR: I want to know who.

E: Good question.

B: What will your brain evolve into with these mechanisms? Yeah, it's dicey and it's very risky but I still want to do it.

SS: I'm with Bob on this. I mean, you can say you're going to keep up but we haven't changed much since the time of the ancient Greeks. The machines are doubling in speed every 18 months. There's a completely different rate of improvement there. I think the interesting question is what James is asking, and that is who's in charge of whom? Right?

S: Right.

SS: And if you go to AI conferences, they talk about instilling moral behaviours in the machines. Which is just code for saying, "how can we be sure to be able to pull the plug?"

S: Right. How do we control them?

SS: Right. And the point is that you can pull the plug for a while. The first generation of thinking machines you can put all the moral codes in there. You can put in Asimov's. You can just tell them, play nice, and maybe the first generation will. But there's no reason to think that the fifth generation, which has been designed by generations two, three and four will care anything about that. It isn't to say they're inimical. They may not wipe you out. I mean, I have goldfish at home but I don't wipe them out.

E: They'll enslave us.

SS: So, you know, I don't know if they'd enslave you, but the point is that you've created an intelligence that's almost orthogonal to yours very quickly.

S: Right.

J: What does that mean?

SS: It means there's no overlap.

J: Well, OK. So, I look at it like this: First of all, I think it is inevitable and we need to talk about it, right? It's one of those things&mdash;

B: Yeah, I agree, I agree.

J: &mdash;that we have to take very seriously and discuss. And I don't necessarily disagree with Seth; I've been reading a lot about the singularity lately and it's becoming a much more scary concept to me now than ever before. I think it is something that absolutely could easily take over humanity and wipe us out. That being said, if it's inevitable, we have to do our magic now to deal with it. We have to talk about it; we have to figure out how we're going to handle it and what we want it to be, shape it now. And why are you laughing at me; what's going on over here?

SS: It's just Jared's looking forward to it; that's why I was laughing.

J: Well, I mean, look&mdash;look forward to it; I get where he's coming from too&mdash;

B: Yeah.

J: &mdash;because, you know, I'm looking at&mdash;like, I think of the singularity like, oh my God, we're going to have so much information; you know, so much incredible stuff that we could use from, you know, all this research; thousands of years or human research could be done.

B: Yeah, of research, in a week, right.

J: And then you know I have this little fixation on not dying, which would be very lovely to happen. Right, so that would hopefully happen as well, and all these good things and all that. But yeah, I see where you're coming from too. I want more people to have your... like, hey guys, you know, don't just put this thing up like it's the best thing since sliced bread. Let's frikkin' talk about it because it's scary and it's dangerous.

SS: Yep. I'm not sure that's my attitude, but I...

JD: I think it's either going to be utopian or dystopian. And it's either going to be the greatest thing that humanity has ever known or the worst. And let's try to embrace it and make it the best. If it's probably inevitable.

J: Yeah, I agree with that.

E: Take our chances.

SS: There's a science fiction story by, which I mispronounce his name but... what is it or Golem 13 or something like that, where the military designs a thinking machine for their own purposes and the machine does its thing for the military. But then, of course, that machine designs the next generation which is a little better, still works for the military. But by the third generation, it's not interested in working for the military. You know, I'm not into that gig any more, right? And very shortly thereafter, it closes itself off from humanity. It's not that it wipes us out, it only wipes you out if you try and cut off the power to the thing. Then it'll wipe you out, but otherwise it has no interest in you.

B: Interesting.

SS: It's like your attitude to the ants in the backyard. You're not going to wipe them out. You're a lot smarter than they are but you're not going to wipe them out. And this machine is doing something. Nobody knows what.

B: That's scary.

J: That's cool; that's really&mdash;

B: That's really scary.

E: Ooh. I don't like where this is going.

J: Well, so clarify your position because you just said you weren't...

SS: I'm all with Jared; let's develop the thinking machines. I think it would be interesting but hey, après moi le déluge.

JR: Well.

R: Did he just become the classiest person here?

Science or Fiction (58:16)
S: All right, then. Well, let's move on to Science or Fiction.

Iszi Lawrence: It's time for Science or Fiction.

S: Each week, I come up with three science news items or facts.

R: But not this week!

S: But not this week, because Rebecca, you're going to take over.

R: That's right.

B: Is this your first one?

R: No, I've done it before.

E: She's done it before.

S: No, she's done a couple. She's done a couple before.

E: We've each done it before.

R: Yeah, this was a terrible decision on my part.

B: Wasn't it? It's harder than it looks, isn't it?

E: A lot of work.

R: Especially when you're prepping for a live show and a trip.

S: You saying I make it look easy?

B: Er, no.

R: No, the reason why I was really inspired to take this on, though, is because two weeks ago, in podcasting time, Steve did a Science or Fiction that&mdash;he likes to do themes, and usually when he does a theme, he specifically picks a theme that I hate and know nothing about. So, that one was I believe carbon nanotubes.

B: Nanotubes.

S: Carbon nanotubes.

R: I could not care less about it. I care; no, I care, I care. I just don't... they do everything, OK; I get it, they're magic.

B: You're disinterested in nanotubes?

R: Right, yes. I'm completely disin... no.

E: Disinterested.

R: So I wanted to get back at Steve, basically.

S: Right.

R: So today's science or fiction&mdash;there is a theme. And the theme...

B: Is unicorns!

R: Close.

E: Rainbows.

R: Close. Sloths.

B: Ooh, I like sloths.

R: The humble sloth. OK. So I&mdash;normally when we do this on-line, we have the ability to send each other the items so we can read them. So in this case, since we can't do that, I'm going to read them and then I'm going to pass around my iPad so you guys can take a look at them.

J: OK.

E: Or other things on there, yeah.

R: Don't look through my porn, please. My iPad porn.

E: iPorn.

R: Has that happened, has anybody? No. Maybe.

J: Somehow I think it's all unicorn stuff, isn't it? (laughs)

R: It's mostly uniporn.

J: (laughs) Uniporn.

B: Unicorn porn.

S: Redundant, but yeah.

R: OK, and also, because Steve did it, there are four items this week.

E: Awww.

J: Oh gosh.

B: I'm surprised you didn't go to five.

R: There are twelve items! No. If I had more time, totally. If the Internet hadn't been so spotty. So here they are; again, one of these is the fiction. Number one: Recent phylogenetic analyses suggest an extremely recent common ancestor between two-toed sloths and three-toed sloths, which occupy the same territory, subsist on the same diet, and even have the same number of toes, despite the name difference. Number two: Sloths move so slowly that a blue-green algae grows on them, living symbiotically within its hollow hairs and providing sustenance for dozens of varieties of arthropods. Number three: Despite the fact that they are incapable of walking, sloths climb down from the trees, poop in a small hole at the foot of the tree, and then climb back up. And number four. Sloths are graceful swimmers who can perform a breast stroke and are descended from an aquatic sloth ancestor. Those are your items. Uuhhh, Bob.

B: Thank you.

(laughter)

E: We love Bob.

R: You just look so pleased right now; you just can't believe your luck.

B: I knew I should have sat over there.

J: Poll the audience, Bob.

S: Are we going to poll the audience?

R: Oh, yeah, yeah, yeah. OK.

S: All right, let's do it.

B: Good.

R: Let me see them again so I remember which one's which.

E: Give them a quick shot, yeah.

R: OK, who thinks the first item is fictional, about two-toed slots and three-toed sloths having a recent common ancestor?

(silence)

R: All right.

E: Whoa, that's a first.

J: Whoa, that is stone cold.

R: Yeah. Number two, the blue green algae, growing on sloths. Who thinks that's fiction?

(silence)

R: I think they're just scared. OK, number three. That sloths are incapable of walking but still climb down the tree to poop in a hole.

(clapping)

J: That was the only one I thought was...

(laughter)

R: OK. And number four, that sloths are forceful swimmers.

(clapping)

R: OK. So it sounds like number three and then number four are the audience favourites.

J: For fiction.

R: For fiction.

B: Uh, the first one, the phylogenetic analyses. Yeah, I can kind of see that, I don't have a problem with that one. The blue-green algae for number two. Yeah, I mean how slow do you have to move for the algae to grow on you? I mean, I think I've got some over... no. But uh, yeah I don't have a problem with that. They move slowly, but that wasn't bothering me either. The third one. Their hands are kind of freaky; they're really curved. I could really see them having trouble walking.

JR: Like Sylvia Brown.

(laughter)

B: That boy's dead.

R: Please do not besmirch the good name of sloths by comparing them to Sylvia Brown.

(laughter)

JR: I apologize.

B: I've never seen them actually walking. Hmmm... how could I not know that? The swimmer one, though, is just kind of freaking me out. How could&mdash;sloths and graceful swimming just don't go together for me, so I'm just going to&mdash;what the hell; I'll pick that one. Who's next?

R: All right, let's just head over to Steve.

S: Yeah, I had the same reaction as Bob when I heard the swimming one; I'm like, wow, that sounds so crazy fiction.

B: That would be too obvious, right?

S: That would be incredible. Yeah, it's almost too obvious; like was that the one that inspired the whole theme?

B: Maybe that's what she wants you to believe.

R: Excuse me, my great love of sloths inspired the theme.

S: An aquatic sloth ancestor. The whole thing just sounded so crazy. The other ones all sound fine. I was trying to remember&mdash;yeah, there's something about the phylogenetic relationship between two-toed and three-toed sloths that's counter-intuitive. I can't remember what it is.

B: You're just saying that.

S: So that might be... no, there is&mdash;there is something&mdash;I can't remember&mdash;it's one of those things. There's something about that that is not what you would think it is, like they're not quite as closely related as the names might imply, both being sloths. But I don't know; I don't remember. The blue-green algae, fine, sure. The walking&mdash;yeah, I mean, you know, sloths climb along trees in the branches. I don't know if they go down to poop but they could certainly do that. I think I have to go with the swimming one, too. If that's true, that's amazing, but that one just struck me as so obvious that I'm just going to go with that because that was my first reaction.

B: GWB.

R: All right, GWB. Evan.

S: Incidentally.

E: Yeah I'll just get right to it. I was thinking the swimming one first, the poop one second. But the audience thinks the poop one is f... a few more people were thinking that one was fiction.

JR: We've been doing a lot of poop this evening.

E: It's been a very earthy podcast.

R: Is that a new medicine you're on? (laughs)

E: They're incapable of walking; also graceful swimmers. Swimmers. I'll go with gang, what the heck. Swimmers. Fiction!

R: All right. Jay.

J: Yeah&mdash;I mean I, the thing I thought of about the swimming is like if you have hooks for hands, like, how the hell can you swim? Like, their hands are just like Bob was saying.

E: Catch a lot of fish on the way.

J: They're like&mdash;remember those monkey toys we had when we were kids?

B: Yes.

E: Yes, you hang them all together.

J: The hooked hands, you could slide them down something.

S: They didn't swim very well.

J: No, but I can't imagine sloths... it's like they can't move but they get in the water and they're like doing Olympic swimming. Like they can barely move. I saw a sloth crawl across the street. It took him like 15 minutes to crawl and there's people, like, blocking. And then you get them in the pool and they take off like rockets?

E: He was thinking, "oh, if only I was swimming."

J: I can't imagine that being true, and this is going to be like such an amazing win for you, Rebecca, because I have to say the swimming thing.

R: All right, what do you think, Seth?

SS: I have to say I don't know anything about sloths except for the guys who are supposedly responsible for maintenance in our high school, so I'm not sure. The only one that I can&mdash;I mean to say "and are descended from an aquatic sloth ancestor". Aren't we all descended from aquatic sloth ancestors? I found it a little bit bizarre that they would climb down from the trees and poop into a hole because I can't think of any evolutionary benefit for them doing that. And it sounds like an awful lot of work. So I'd say that's the one.

R: So you're going with...

B: If you're in a tree, why not just crap from the branch, right, and let it drop?

JR: Well, I'm going to poop on the poop one. Yeah, I can't see them climbing out of trees and digging holes; that's a little too civilised for me so I'm going to turn that one down. I think that's a loser.

R: You're going with the poop.

J: OK, there we go.

R: All right. Should we poll the audience?

J: Yes, let's poll the audience again.

R: All right, so let's see if they swayed you guys at all. Who thinks that the fiction is the two-toed sloths and the three-toed sloths having an extremely recent common ancestor?

(silence)

R: Still no one. OK. Who thinks that the fiction is the sloths getting a blue-green algae?

(silence)

R: All right. Uh, poop!

(clapping)

J: Wait, we just said, people clap for poop! That was the whole point for the past two hours.

R: That's the only reason I included&mdash;And sloths as graceful swimmers.

(clapping)

R: It's still pretty even between the two. All right. I'm going to take them in seemingly random order. Let's start with the algae. Everybody seemed to buy into that pretty quickly. Sloths move so slowly that a blue-green algae grows on them, living symbiotically within its hollow hairs and providing sustenance for dozens of varieties of arthropods. That is in fact... science. So, well done. Yeah, it's kind of cool; they do in fact move that slowly and the algae helps protect them because one of sloths biggest predators are raptors, not veloci- but you know, flying.

S: Birds with talons.

R: Yeah, and when the sloth is covered in the algae...

B: Camouflaged?

R: ...and just sort of hanging there, they look exactly like a big clump of leaves.

B: Cool, symbiotic relationship.

R: And yeah, they have this incredible almost ecosystem of bugs all over them. It's really pretty.

S: That's what happens when you don't move.

JR: Sounds yummy.

B: Which is another good reason why they wouldn't swim. All right. I'm just throwing that out there.

J: Oh, sh...

E: Oh wow.

R: All right; let's go to the other one that everybody thought was science, which is recent phylogenetic analyses suggest an extremely recent common ancestor between two-toed sloths and three-toed sloths, which occupy the same territory, subsist on the same diet and even have the same number of toes despite the name difference. That one is in fact... fiction! You all lose!

B: Oh, no way!

R: You all lose! Yeah, I thought Steve was going to get it.

S: Yeah, I was; I (groans).

R: I really thought you were going to do it.

S: I knew if I remembered what I was supposed to remember about that I probably would have gotten that one.

R: The science part of that is that two- and three-toed sloths do in fact share the same territory that they have the same diet, the only real difference between them is size difference, but that's the really fascinating thing about them. They're so similar but their common ancestor is incredibly distant, incredibly distant. They've just...

B: Convergent evolution.

R: Yeah, it's a beautiful example of convergent evolution.

B: I hate convergent evolution.

(laughter)

R: Damn you, convergent evolution!

E: Damn you, God!

R: Yeah, because they occupied that same area, they were under the same pressures and they evolved in pretty much exactly the same way. And actually, let me pull this note up...

J: You're really passionate about these guys.

R: I love sloths!

B: How could you not know that?

J: So do they have hooks for hands?

R: Like Captain Hook. That's what you're picturing?

E: Arrr.

J: I mean, I can't...

S: They have curved claws, yeah.

R: They have claws.

B: You see them on branches; they just kind of hang upside-down.

R: Oh yeah and that's the other thing. Despite the name, all sloths have three toes. But their claws, which are technically on their sloth-hands, two-toed have two claws, and three-toed have three claws.

S: Have you ever held one?

R: No. I would die. I would melt.

B: Yeah, from all that algae and stuff.

E: Yeah, and the bugs and whatever else.

R: Uh, here's a cool thing about sloth evolution: I found this quote from a researcher. Even the animals they are most closely related to, anteaters and armadillos, are as different from sloths as whales are from bats.

J: Wow.

E: Sweet.

JR: That's a big difference.

R: Yeah, I thought that was really cool.

B: Different genetically?

R: So let's go and do the other two, even though you all lost and it's pretty much, you know. It's done now. The poop thing: so despite the fact that they are incapable of walking, sloths climb down from the trees, poop in a small hole at the foot of the tree, and then they climb back up. That's science.

J: But they are so slow, they have to actually think, "I'm going to need to poop in about four hours."

(laughter)

R: Here's what that... I almost put this as the item, which is, "sloths&mdash;this is true&mdash;sloths poop once a week."

J: Wow.

B: That's awesome.

R: Sloths have such incredibly slow metabolisms.

E: Incredibly constipated.

J: They need fiber!

JR: That's one hell of a poop!

(laughter)

JR: Stand back!

R: Actually, you are absolutely correct. I read a paper that said that 30% of their body weight in one evacuation was not unheard of.

B: Wow, Jay you've done that; you've done that.

R: Again, why do you guys know so much about Jay and his poop?

B: He posts it on Facebook.

R: So yeah; sloths do not poop in the trees and there are a number of guesses for why they do this; there's no solid evidence but some of the guesses...

E: Ew.

JR: I got it, I got it.

R: Thank you.

S: You don't crap where you eat.

B: But they're in a tree; just let it drop.

S: But they're upside down.

B: Yeah, OK.

R: Faeces dropping from the tree are a signal to predators, like the birds that are hunting them...

J: Oh, right.

JR: They get out of the way.

B: Yeah, right; but they've got the algae to protect them; they're cool.

R: Exactly, though; the algae does until the sound happens and then the birds are very good at swooping, and there's video if you can stomach it; there's actually video of a bird swooping in and flipping upside down and grabbing a sloth right off of a tree branch and carrying it away.

B: Aren't they big though? I mean aren't...

R: You know, they can be like&mdash;they're I figure like a cat size&mdash;large cat, sometimes.

B: Really? I thought they were a little bigger.

R: Well, two-toed are small, three-toed are a little bigger but there are some large birds that can easily snatch them.

JR: You're really fascinated with these, aren't you Rebecca?

R: (laughs) A little bit, a little bit.

B: Tell me, no.

R: There's another possible reason for not pooping from the tree and actually going down and burying it, and this is a bit more difficult to believe, but it is interesting. The poop fertilises the tree; burying it right under the tree fertilises it and produces better food for the sloth to go eat.

E: Ooh, nice.

JR: So they're farmers.

R: Yeah, they're basically farmers.

B: Hey, tell me about extinct giant slots. Weren't they like huge at one point, like bears?

R: We talked about it.

E: Mammoth.

R: I did a This Day in History a few weeks ago about Jefferson discovering what he thought was a lion. Or he didn't discover it, but he delivered a paper on it.

B: Oh yeah.

R: He thought it was a lion and asked Lewis and Clark to find it on their expedition.

S: Yeah, it was a giant sloth.

R: They didn't because it was an extinct giant sloth.

B: Cool.

R: And that was another potential item, was that like Bigfoot in the US, in South America there's a common myth of a giant&mdash;a living giant sloth, only it's not just a giant sloth, it's terrifying. It's still very slow.

B: If you stand still for 8 hours you're in deep shit.

(laughter)

R: But like, you know zombies&mdash;very slow, very scary. It can happen.

J: What movie was that from? There's a steam roller coming at a guy and it's moving like a half a mile and he's like, "aaaaargh!"

S: A Fish Called Wanda.

E: Austin Powers.

S: He was cemented in, that's why he couldn't move.

(general agreement)

J: So holy shit, I just realised something: they can swim like crazy.

R: They can swim! They can swim.

B: Oh, come on. I want to see a YouTube video.

R: There are tons of YouTube videos on it and they are amazing.

E: There is a sloth channel on YouTube.

R: So they do have an ancestor that was probably a mostly aquatic sloth. There's really good evidence to suggest. They found these fossils and they looked particularly at the teeth. And they found that older versions of the sloth&mdash;this is technical language; it's very late. Aquatic sloth 1.0 had teeth that were really nicked up and what they figure happened was that it lived in a desert area that ran into some water and the only plants around were by the water. So the wear on the teeth they think came from sand that they scooped up as they were grabbing plants on the edge of the water. But later versions of the sloth, they found that the sand was beginning to disappear and the only explanation they can come up with is that the sloth was moving further and further and further into the water until it was completely in the water and just foraging on aquatic plant life. So they do have that ancestor and right now there are sloths that live in areas that can be flooded and when that happens, they literally can just drop out of the tree and immediately start swimming and they do this breast stroke. I found one thing that I could not verify was that depending on which way they land they will do either a breast stroke or a back stroke.

B: Or a back stroke, awesome.

(laughter)

R: Because the Internet connection was so low I couldn't find a video of the backstroke so I didn't include that. But I thought that that was pretty cool. They are very good swimmers and you can find it on Youtube.

J: Good job Rebecca; that was good.

B: Good job; nice.

(applause)

J: And Rebecca, you've stumped more people at one time than anybody else ever.

R: Awesome. I'll take it.

J: That's pretty cool.

R: This has been sloth facts with Rebecca. There was actually one other thing that I wanted to mention that I thought was really interesting but I tried&mdash;I could not verify this. But in Salmon of Doubt, Douglas Adams' book, Douglas Adams says that his favourite fact is that young sloths are so inept at climbing that they often mistake their own arms and legs for tree limbs and they fall.

(laughter)

B: Oh my God. I don't remember that part.

R: The best I could confirm was that there is evidence to suggest that climbing amongst sloths is a learned behaviour. And so that could suggest that yeah, maybe baby sloths are morons at climbing.

(laughter)

R: But yeah, I couldn't find any&mdash;no video evidence of baby sloth like rrrrr, falling down. So yeah.

S: OK. Good job, Rebecca.

R: Thank you.

Skeptical Quote of the Week (1:17:46)
S: Um, Jay do you have a quote to end our live show with?

J: I have a quote from the incredible Carl Sagan. This was actually from his Cosmos TV show. And the quote is: "The suppression of uncomfortable ideas may be common in religion or in politics, but it is not the path to knowledge, and there's no place for it in the endeavor of science. We do not know beforehand where fundamental insights will arise from about our mysterious and lovely solar system. The history of our study of our solar system shows us clearly that accepted and conventional ideas are often wrong, and that fundamental insights can arise from the most unexpected sources." J: Carl Sagan!

(laughter)

R: Thank you.

(applause)

S: Thank you for joining us, everyone. Randi, thanks again for joining us; Seth, always a pleasure to have you on the show.

J: Thanks, guys.

S: Thank you guys for joining me this week, and thanks to our live audience.

E: Great week. Great week, guys.

(cheers and applause)

R: Thank you. Good night!

S: And until next week, this is your Skeptics' Guide to the Universe.