SGU Episode 350
Working on this, as of 10/4/2012
- S: Steven Novella
- B: Bob Novella
- R: Rebecca Watson
- J: Jay Novella
You're listening to the Skeptics' Guide to the Universe, your escape to reality.
Hello and welcome to the Skeptics' Guide to the Universe, today is Wednesday March 28th 2012 and this is 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: Welcome to episode 350!
S: 350 that's right
E: three fitty
R: Hooray! A round number
S: Yeah, an arbitrarily round number
J: does that mean I can retire now?
S: if you want, Jay, you can retire whenever you want, man.
R: No!
J: I"ll go another 300, OK let's go
E: Three fitty
S: and we're coming up on our seven year anniversary, a couple of months.
B: Holy crap
R: wow
E: I've gotta look up what to get you guys this year
R: Guess what today is!
J: Not your birthday
R: Jay is right, it is not my birthday
S: It's your un-birthday
R: No! ON this date in 1981, March 31st, Indian American microbiologist Ananda Mohan Chakrabarty received the first ever patent for a living organism.
B: Cool
R: it was me! No, just kidding.
(laughter)
S: that explains a lot
R: it was right after I was born though, and that would have been epic. Uh, no he created a new species of oil eating bacteria called pseudomonas?
S: Pseudomonas
R: Pseudomonas?
S: Pseudomonas
R: I'm going to say Pseudomonas because it sounds better. Putida, which sounds filthy, which turns oil into simpler substances which can be eaten by aquatic life. He genetically engineered it because there are already four species of existing oil metabolisers, but they apparently competed with each other for the oil. So he made this new species that consumed oil an order of magnitude faster than the others. And it was a very interesting case because initially when he applied for the patent, it was denied, and then he appealed and the US court of customs and patent appeals overturned it. And then it went to the supreme court, and on March 17th 1980, the supreme court case was argued, June 16th 1980 the supreme court decided 5-4 in favour of Chakrabarty. And so on March 31st of the following year the patent was issued, and that paved the way for other genetically engineered micro-organisms and other things to be patented.
S: yeah, the issue was whether or not you could patent a living organism. And yeah he won that, that was a landmark case. Interestingly, how he made the organism was to plasmid transfer. There are examples in all of the domains, but bacteria especially can have part of their genetic information bound in these small circular usually transferable units called plasmids. That's how bacteria can exchange genetic information with each other, they can transfer antibiotic resistance, for example. So he took the oil eating genes from four different plasmids and he found a way to make a stable new plasmid thereby creating this new super oil eating bug. Pseudomonas Putida. And it is related to a lot of other species that do lots of neat things, you know, breaking down not just oil but also toxic chemicals, insecticides, it really can clean up the soil with all kinds of nasty chemicals in it. Some of them, however, can be human pathogens, so most of those are banned, you know, you can't really use those. The pseudomonus putida, however is not, it's a safe bacteria, so this is actually a really useful one.
B: Well, where the hell were they last year, I mean what's going on, that was so long ago, what the hell?
R: Well, they just don't work fast enough I guess. They're not efficient enough to take care of our large-scale disasters.
S: well, the use of bacteria in the deep horizon spill is complicated actually, first of all, there are a lot of different chemicals in crude oil, that were released from that spill, a lot of different types of molecules, and bacteria could eat some better than others. It's still controversial what impact bacteria had on biodegrading the oil spill and also there are concerns that bacterial overgrowth in the gulf can cause problems: health problems for people living on the coast, perhaps even depletion of oxygen in the waters, and other environmental effects, so they're not a magic bullet
E: we need to develop an organism that could eat up carbon emissions, wouldn't that be handy?
S: Yeah, they're called trees.
(laughter)
E: more trees!
R: zing!
E: we need, what eight times as many trees? 10? 12?
S: well, it's also just phytoplankton, it's just a matter of how much of it we have.
E: yeah.
R: I think that there was, speaking of things that can conveniently eat things for us, there was recently a plastic eating fungi that was found that you know, would obviously help a great deal in terms of the huge amounts of waste we produce.
E: he's a fun guy.
S: down in Tennessee though, they're not having such a great time, I understand they're having some creationist shenanigans going on down there.
R: correct, they are. Yeah, last week I talked about the news of an anti-science bill in New Hampshire, and this week's story is another anti-science bill that's passed through the state senate so far of Tennessee. The crux of it is that the creationists are continuing to sneak their creationism into science classrooms, this time with a bill that would protect the jobs of teachers, and I quote "teach the strengths and weaknesses of topics that" I quote "can cause controversy" And these topics include global warming, human cloning, and of course our old favourite, evolution. Of course, they're not talking about scientific controversy because you would have to be pretty ignorant to think that there's any scientific opposition to the theory of evolution. No, what they're actually talking about is their own made-up religious controversy in which they're having trouble marrying a literal interpretation of the bible with reality. So the really amazing thing is the language that they use in this bill to justify themselves. They're actually co-opting our language. Let me read you a part of it. An important purpose of science education is to inform students about scientific evidence and to help students to develop critical thinking skills necessary to become intelligent, productive and scientifically informed citizens. That sounds pretty great, right? We agree with that. The bill states, though that when it comes to controversial subjects, and I quote "some teachers may be unsure of the expectations concerning how they should present information on such subjects. Those subjects being evolution, cloning, global warning. One of the big issues that's been brought up by opponents of this bill, opponents that include every scientific advocacy group ever, pretty much. They rightly point out that it's the job of state science standards to make sure teachers have the tools they need to present materials, not the job of a bunch of conservative Christian law makers who wrongfully think that they're the ones who should be insulted when we point out that they're related to monkeys. So it is yet another one of those bills that is in the wedge strategy of creationists, you know, change up the language a little bit in order to protect teachers who will go ahead and start teaching creationism as a way to teach the weaknesses of evolution. And once they let that through, they'll keep pushing and pushing and pushing until they've got creationism recognised as some sort of official topic for science classrooms. So, people in Tennessee, please let your representatives know how you feel about this. As I said it's passed the senate, it has gone to the house now.
S: It passed the house this week.
R: well, shit (laughs). There's still hope. There's still hope that the governor may go ahead and veto this, he did make some rumblings about how this should be up to the science standards, not lawmakers.
E: hey!
R: So, yeah.
S: yeah, it sounds like he's making a legal justification for vetoing it, not because it's the wrong thing to do, or not a scientific justification, it's just not in the purview of the legislature to step on the board of education, it's their job to do this. But that may just be a politically acceptable way for him to veto a bill he knows is bad. It's also a bad bill, the science aside, a lot of people are critical of it because the only net effect of this bill is to create million-dollar lawsuits on the back of the taxpayers, this is just wasting Tennessee taxpayers' money, because it's going to generate lawsuits that they're going to lose because we already have enough precedents to know how the higher courts are going to rule in cases like this, and it's utterly transparent what they're trying to do here. But you've got to love the long term strategy here. They make this fake controversy over evolution, and then they say, oh and because we made it controversial, now we have to pass laws to water down the teaching, to teach the contravener essentially. But really what the sweet-spot goal of this bill is to provide cover for teachers to teach creationism in the public school, so that the hope is more science teachers who are creationists will have the courage to do just that, to present creationist arguments without worrying about being fired. Because they'll say, hey I'm protected by this bill, I'm just doing what it mandates, to teach the strengths and weaknesses of evolution.
J: it's our role as critical thinkers in the community to point out these things because you could just imagine how this would just go right over the heads of our politicians, they'd never find this, or discover this on their own, right Steve?
S: I don't know, I guess it depends on how savvy the politician is, but yeah I mean it's certainly, the fact that there's a sceptical community and specifically the National Centre for Science Education and Genie Scott who keeps an eye on these things, we have to be right there and say Nope, this is what this bill is all about, this is a stealth creationism bill, this is the goal, this is why it's anti-science, this is all the things that are wrong with it. It certainly makes it more likely that politicians will get the message. But let's more on. Bob, you're going to tell us, or give us an update about thinking about the origin of the Earth's moon.
B: Yeah, the moon was in the news again this week, it seems this past year it's been in a bunch of times. Recently scientists seem to have obliterated the most popular moon formation theory by finding new compelling evidence that the moon is not made up of bits of Earth and another planet that hit us 4 billion years ago.
J: or cheese, bob
B: or cheese, yeah, they debunked that last year, Jay. For years now, the prevailing theory of the formation of the moon was the giant impact hypothesis, a Mars sized planet called Thea hit us, spewing debris from both planets into orbit around the decimated Earth. Is spew the right word there? I kind of like it, I"m going to go with it. After a century or so, this debris kind of gravitationally coalesced into the moon that we know and love. So there was little research that cast doubt on that scenario. Even a weird oxygen isotope comparison couldn't really put a dent in it. Different isotopes of an element like oxygen for example, have the same number of protons but a different number of neutrons in its nucleus, years ago they compared oxygen isotopes from Earth and those found in moon rocks and they discovered that the ratio of isotopes were the same. So that means that when they compared the ratio between say oxygen 16, 17 and 18, those three different isotopes, they were the same on Earth and the Moon. This seems odd though, because normally you'd think that since the planet Thea comprised perhaps 40% of the moon, the ratios would be different. And that ratio is important because it's kind of like a fingerprint, every planetary body out there has a unique genesis, that they formed in very unique circumstances, and so their ratios of the various isotopes would be different, so...
S: So bob, on that point though, I understand why that's the case, but you could also think, well everything in the solar system formed from the same cloud of dust and gas, why would the isotope ratios be so different for one hunk of rock that formed one place in the solar system and another hunk of rock that formed some place else? But from remembering correctly, I believe it has to do with the distance from the sun, you know the relative gravitational strengths and etc. do actually create this sort of layering out of different isotopes
B: right
S: and so the exact location in that cloud does affect the isotope ratios, right?
B: yeah, that makes a lot of sense, I mean you're not going to have a completely homogeneous mixture in that cloud, and that's pretty much the thinking of why there should be some difference, some detectable difference, but which they really didn't find when they compared these oxygen isotopes, but you know those crafty scientists, they explain this away, they explained away this apparent anomaly saying that it's very possible that Earth's oxygen mixed with the oxygen in the orbiting magma soon after the collision, so nobody really had a problem with that, and that's fine, it makes a lot of sense. But now, however, they found another isotope ratio that can't be explained away so easily, and this time it wasn't oxygen, but titanium. SO what they did was they compared titanium 50 with titanium 47. The ration between the 50 and the 47 is the same for the Earth and the moon and this is why essentially the old Earth collision theory, the big impact theory may actually now be dead. For oxygen, exchanging is possible as I just said, there is a mechanism that might explain it, but for titanium a similar type of exchange is essentially impossible, and that's pretty much, as far as I could tell, due to its very high boiling point. So this is an anomaly that really stands out and really is at odds with the current theory. So how do we then explain that the geochemistry of the moon seems identical to the Earth? So let's look at a few of the earlier Moon formation that were bandied about years ago.
S: well bob, before we... I'm not sure I'm ready to get rid of the impact theory here just on one line of evidence. Is it possible this is just sampling error, or the idea that this is just too small a sample to make a generalisation from?
B: you know, I thought about that, and I'm just going with the scientists here on this one, thinking that that's just such an obvious issue, that they had to account for it by taking moon rocks that were gathered at different points of the moon, and yeah sure we're going along with the assumption that they believe that Thea comprised 40% of the moon, and that could potentially be incorrect which would impact this, but to me Steve...
S: but couldn't they have sampled it from one of the 60% that's from earth?
B: yeah, I'm sure that's possible, but I thought about it and that just seemed like that's too obvious for them to have missed so I'm just kind of going with the scientists on that one
S: yeah, but how do you know how accurately the reporting is reflecting the real consensus of opinion, or have they just talked to one guy? You know what I mean? We don't know that the reporting that you're talking about is really a consensus of scientific opinion, or is it just some of, a narrow opinion that whoever is doing the reporting is presenting as...
B: well I've read some of the abstract and that seems to be the angle they're going for here, so yeah maybe it's a little premature and there won't be a consensus on this, maybe there's something that they're missing, sure that's possible. But it seems like a significant blow to this theory that has held sway for so long.
S: yeah.
B: and definitely, yeah, more research, let's get some more lines of evidence going, let's look at some other isotope ratio comparisons, absolutely
S: yeah
B: so maybe I'm being a little bit too definitive in this.
S: it just seems a little early to toss out a perfectly good theory because of one piece of evidence that doesn't seem to fit.
B: yeah, sure I'd have to agree with that, so let's see how this plays out before we make more definitive statements
S: well what are some of the other theories
B: well there's the capture hypothesis that says that the moon came in from outside the solar system or other parts of the solar system and that the earth pretty much captured it, and that's really not viable because if this was a distinct body that did not co-mingle with the Earth, then the isotopes should be obviously different, which they're not, and also I recently discovered that the Earth, for this to be a viable idea, the Earth would need a hugely extended atmosphere to dissipate the energy like the moon passing by, so that theory I guess fairly quickly, maybe not quickly but it's pretty much not highly regarded any more for these obvious reasons. There's also, this one was good, an ice collision, you know if it wasn't a planetary body, it could have been a gargantuan chunk of ice that hit the earth, the evidence would then have evaporated away, there wouldn't be much left of it to mess with the isotope ratio. I don't hear much about that theory though, I don't think it's held in very hard regard. There's the spin theory, I remember this one as a kid. That there was no collision but the rapidly spinning Earth spewed chunks of itself into orbit, but the problem with that is that this would require the Earth to have too great of an initial spin, that they really can't explain so that's pretty much not believed any more. There's the co-formation theory, that the Earth and the Moon just were created at the same time and I remember seeing animations of this theory, how they're just kind of these spinning balls and gas forming together, so they're just companions, twins that were just created the same time. But I think that the Achilles heal of this theory is that there's so little metallic iron in the moon that that theory is kind of defunct. This latest theory could perhaps suggest another hypothesis or another theory, maybe called the collision spin theory, which is kind of like a fusion of the collision and the spin ideas, and the idea here is that a glancing blow from a planetary body, a blow that would have the effect of causing the Earth to spin much faster but not really, I guess it could be such a glancing blow that there really wasn't any major exchange of material, and this other body just kind of, for the most part just kind of went on its way after slightly impacting the earth, if that's really even possible. And because it increased the rotational speed of the Earth, then you'd segue into the spin theory where this piece of the Earth is just extruded away and becomes the moon, so I think that's kind of like the preliminary hypothesis they might be going with that would kind of work with this discovery. But of course there are issues with this new idea as well that need to be worked out, such as the angular momentum.