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SGU Episode 37 |
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April 6th 2006 |
(brief caption for the episode icon) |
Skeptical Rogues |
S: Steven Novella |
B: Bob Novella |
R: Rebecca Watson |
E: Evan Bernstein |
P: Perry DeAngelis |
Links |
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Show Notes |
SGU Forum |
Introduction
You're listening to the Skeptics' Guide to the Universe, your escape to reality.
News Items
Fish Evolution (3:34)
Prayer in Medicine (14:13)
Questions and E-mails (24:07)
Well, let's move on to your e-mail. We did get a usual crop of e-mail—actually, we get an increasing number of e-mail every week, so thanks for sending them in. We're going to talk about a few this week.
Noah's Ark (24:18)
The first one is from Keith Bentrip, who writes:
Hi guys, I love your show. I've listened to every one by now. I have a couple of thoughts about the Noah's Ark segment from 3/22. I couldn't verify the comment about two of each predator and seven of the rest, although I did find references to seven of the clean and two of the unclean.
Actually, I think it was—I looked it up myself; it was two of the clean and seven of the unclean, I believe. But that's what I was referring to, and in other translations it was seven of the domesticated animals. So there would've been seven cows and seven sheep and seven pigs. But only two lions and two tigers and two giraffes.
Also, would any of you
Oh, he wrote "would" twice.
Would any of you care to hypothesize just how big the Ark would have to be to house two of each species today? How much food would they have to carry for the duration; how much is the minimal amount of space they would need, etc.? It'd be an interesting thought experiment. Also, any insight into the geological evidence that we would expect to find for a mass extinction of that size? It would be interesting to hear some off-the-cuff remarks. Or if you know some on-line resources that already does this, I'd be grateful if you could point that out.
So... well, Keith, there are on-line reviews of that very question on talkorigins, and we'll have that link on our Notes page, of course. And in the Skeptic's Dictionary were two that I quickly found. They go through calculations as to how many species—how many individuals animals would've been on the Ark. There are, by the way, ten million species that have been identified. There are more—the number would be higher 'cause there are some that are not identified. But if you eliminate all of the swimming animals, you know, that wouldn't have to go on the Ark, it's a lot less. Even if you just count, like you know, birds and reptiles and mammals and amphibians, it's still tens of thousands of species, so tremendous, tremendous number of individual animals would've had to have been on the Ark. The Ark was not big enough, frankly, to hold all those animals.
R: Steve?
S: Yeah?
R: Steve, sorry. Are you sure it's ten million identified species? I thought we were only at, like, two million, but we assume that we could go up to ten.
S: Actually, you are correct. The total number of named species is right now around 1.7, 1.8 million. The ten million figure is an average estimate for the total number of species in the world. Estimates range from about 5 to 20 million, although some people advocate a much higher number. Even if you take an average estimate, it's about ten million, which is, of course a more relevant figure for the Noah's Ark question, rather than the number that we've just happened to name by this point in time.
R: OK. Wow.
P: That's a lot of species.
S: It's a lot. But even if you... even a much smaller number would be far too—although most of those are insects. In fact, most of those are beetles.
R: Right.
S: But even if you eliminate all of those, it's still quite a few... quite a few species. Also there's a problem with feeding them. They all have different kinds of food—you know, where would the pandas have gotten the bamboo shoots, etc. What did all the carnivores eat? They would've had to eat the other animals, right?
P: Right.
B: Not to mention excrement. Hello!
S: Well, yeah, they would've had to have a massive effort just to keep the ship from sinking under its own weight in excrement.
R: Well, you know, actually, I crunched a few numbers on that, if you want to hear some of them.
S: Sure.
R: It's kind of funny. I found out that the volume of the Ark was about 45,000 cubic meters. And if you only considered a million animal species going onto the Ark, that would leave about 5% of one cubic meter per animal. And to kind of compare that, a human takes up about 20% of a cubic meter. So, for just a million animals, you'd basically be packed in there like a clown car, basically.
S: A million animals averaging in size, like, a rabbit or something.
R: Yeah.
S: Or maybe a small dog.
R: Yeah... instead of like, clowns, it's sort of like a tiger, you know? (laughs)
E: Fold them up. Fold them up neat.
R: You'd have to be, yeah, really comfortable with other species. And so, that's just space-wise. If you looked at weight, I found a source that said that the Ark could probably hold about 50 million kilograms. And I found another source that said... that gave an average weight of an animal; they guessed about a horse, about 450 kilograms. This is very un-scientific, but that's the best I could find. And if you only went with 1.5 million species, that would end up at 675 million kilograms. So to hold all of the species, if you just went with 1 and a half million species, the Ark would've had to have been about 13 times larger than what the Bible says it was.
S: Right.
R: It would have to have been about 6,000 feet long, 1,000 feet wide by 600 feet tall.
E: Can you express that in cubits, please?
(laughter)
R: Um, no. (laughs)
P: Ye of little faith. Remember the mysterious ways back in the other segment? Same thing here. Mysterious ways.
S: Right, right.
R: To contrast it, the largest ship in the world that's currently being constructed is about three quarters of that size. That the Ark would have needed to be. And that ship hasn't even—that's still in the conceptual stage. They might not even be able to make it.
E: I hope we're building it.
P: Perhaps God dehydrated and they were in powdered form.
R: That's a good point, actually.
E: Freeze-dried. Just add water.
R: Just little jars of animals.
P: You don't know. You don't know!
(laughter)
R: Where's your science now?
S: In terms of geological evidence, I mean, there is no evidence of a worldwide flood ten thousand or whatever years ago. And the other thing is, even if you could somehow get all those animals onto the Ark, survive the flood, release them, you still have a huge problem of... that's not enough time for all of the genetic diversity to re-establish itself. You know, if you have only two, a male and female of a species, the probability that that species will even survive is pretty low; it's less than 50-50.
B: Yeah; Steve, you can't produce a viable community of animals with just two. It's impossible!
S: It's not impossible, Bob. It's not impossible. It's very difficult.
B: Two? Starting with two?
R: Adam and Eve did it.
S: You'd have to get very lucky. It is theoretically possible with just two species [sic], but you have—the big problem is that you have so little genetic diversity. And if they happen to have—match up a lot of recessive genes for bad things, they're not going to survive. And of course, their children would have to be consanguineous, and... that's where you get into the problems. It depends on how different the two individuals to start with and how many recessive genes there are for genetic disorders, etc. But it's a long shot. It's a long shot. In fact—
B: It's a long shot for one species, I guess.
S: For each species. That would be for every single species.
B: Right. Multiply that by all those species and you're talking...
S: And once the lions started eating the zebras, I mean, they would be... you know, they would be gone. What did they eat? It would take multiple, multiple generations to re-establish a herd. So it's completely, completely implausible. What I was going to say was that the... it is estimated that in order to have a stable breeding population, you need about 2,000 individuals.
B: Right, that's what I heard.
S: Two is tough. Not impossible, but very, very tough. So, we'll have a couple of links on our website, but that's the nuts and bolts for you.
P: The whole thing is bananas.
S: Basically.
R: Scientifically speaking, yes.
S: Don't get technical on us, Perry.
P: (chuckles)
E: Speaking of bananas...
EVP (32:07)
More on the Solar Eclipse (41:54)
Frank's Questions (44:32)
S: Let's do... let's go on to the next e-mail. This is from "Frank the Skeptic". Frank has a few questions, which are all good, typical questions, so we wanted to address them. Frank writes,
I discovered your podcast a couple of months ago and have listened to most of them. Thanks for the great shows. They are fabulous.
Well, thank you, Frank. Let me get on—he talks about some other things, but let me go on to his questions. He says,
In the meantime, I'll propose some tidbits to stimulate debate amongst yourselves and give a chance to flex your big brains.
Yes, we always love the chance to flex our big brains.
Big Bang and Conservation (45:00)
Number one: The law of conservation of energy and matter says that energy and matter cannot be created or destroyed, but only changes form. Scientists believe the universe began with a Big Bang, which is essentially a theory that states that the universe exploded outward from an infinitesimally point at a specific point in history. If you assume that the universe is not oscillating, a point on which most cosmologists are now in agreement, then you must conclude that the universe was created out of nothing 14 billion years ago. Therefore, current scientific theory is an inconsistent belief set.
Well...
B: Steve, I'll take this one.
S: All right, Bob, you take the first shot. Go ahead.
B: OK. Uh... he is correct that, essentially, it seems that it came from nothing, and it might seem like, well, how is that possible? How does that—doesn't that violate the law of conservation of energy? But... it was created out of nothing—it really seems like it was created out of nothing, but energy conservation remains intact because we're still essentially nothing right now. This is because of two things, and it's kind of interesting that all the positive energy of the universe, like matter and antimatter and photons is exactly balanced by the negative energy of the universe, namely gravity. Therefore, the total net energy of the universe is zero. The universe is the biggest free lunch [imaginable], and that's how you kinda get around that issue is that everything balances out so the net energy of the universe is exactly zero. So there is no problem with conservation of energy.
S: That's right. It's also... point out that when you're talking about cosmology, especially beyond the known universe, both temporally and physically, it's hard to know if the laws that we've come—that we've described in the known universe hold true. We don't know if conservation laws hold true inside a black hole or at the singularity before the Big Bang. In fact, we don't know if it's really even meaningful to say "before the Big Bang". And in fact, some cosmologists have postulated that although the universe is temporally bound, meaning that it is finite in its life span—it did not always exist—that it may not have had a beginning. I'm not going to attempt to give you an explanation of why that is true. If you want to know about that, then read Stephen Hawkings [sic]. But there didn't necessarily have to be a beginning to the universe in time, and therefore a "before the Big Bang".
B: Yeah, that makes sense to me because one problem I have with things happening before the Big Bang—the universe—when the Big Bang happened, it wasn't like a firecracker going off and... an explosion.
S: Right.
B: It's an expansion of space and time. So before the Big Bang, space and time did not exist, so if time didn't exist, how could anything happen?
S: Right. Exactly. So you can't really—it's not a meaningful question.
B: Right. It is; it's meaningless.
S: And saying, "where did the matter and energy of the universe come from?" is not a meaningful question either. We don't have—
B: Well, there's an answer for that.
S: There kind of is, but we really don't—we don't have a language really to even ask or answer that question.
B: Right.
S: You know, is the bottom line.
B: I agree. Yeah... I've read a little bit about this, and there's... one guy was saying that, at astrosociety.org, was saying that all that would be required is just a tiny bit of energy to get the whole thing started, and... but that's...
S: Fluctuation.
B: Yeah, it's quantum fluctuations and things analogous to virtual particles, but it's... I don't know where that would've come from, but it's interesting.
S: But there's no violation of conservation of mass implied in the Big Bang is the bottom line there. I would also point out—this is a total tangent, but creationists have also liked to point out that the scientific model requires that there has been a decrease in the amount of energy in the universe because the universe began as a uniform cloud of hydrogen gas, and now we have people, and doesn't that represent a decrease in total entropy? The laws of thermodynamics say that entropy should be increasing with time. In other words, disorder... actually, "disorder"'s a very bad analogy to entropy; it's actually not correct. But that's sort of the misconception that they make. But the bottom line is, they argue that the increase in complexity of life and, in fact, matter that scientists and cosmologists propose happened violates thermodynamics because it represents a decrease in entropy when entropy should be increasing over time. Well, in fact, the modern cosmological model does represent an increase in entropy. Entropy is increasing over time, even given the evolution of life on Earth and the development of stars and planets, etc. Because when suns burn hydrogen to make helium, and then eventually heavier elements, they are dramatically increasing the entropy of the universe, and the evolution of life on Earth represents only a tiny reversal of that entropy. We're just recovering a little bit of that energy to carry on the processes of life, one of which is evolution. So, it kinda reminded me that it's similar; it's like, entropy is increasing as time goes by, inevitably, and nothing that happens, or that scientists believe happens, or has happened over the last 14 billion years, violates that. So, the laws of the universe are still well in place.
Detecting Altered Photos (50:38)
Question number two: Can experts tell with 100% accuracy if a photo has been digitally altered? Can they tell with 100% accuracy if a photo has been doctored in any way? Everyone thinks they can spot a toupee, but it's only the bad ones they spot; the good ones aren't even noticed. Could you use this argument here?
S: That is a very good bit of logic. If your criteria for saying that something exists—you noticing it, then all you're really seeing are noticeable things. You can't rule out the un-noticeable phenomena with that criteria. But regarding photographs... the short answer is: yeah, pretty much. And the reason is that any technique you can use to alter a photograph, an expert can use that same technique to detect the alteration. As far as I know, and I have not been able to find any documentation that it's possible to alter a photograph significantly without leaving a tell-tale sign behind. You can do, for example, statistical analyses on the subtle shades or colors in a photo, and they should follow the laws of randomness and statistics, and any manipulation that you do to that photograph is going to leave a non-random signature behind, a statistical sort of signature behind. So, if you have the techniques to look at a photograph in that way, basically do a statistical analysis of the pixels, you can detect any manipulation, is the bottom line. But that doesn't apply to filters and things like that; I mean, you're talking about like cropping out a picture and moving it over or actually altering the content of the photo. There are also ways detecting filters and things like that, but that's not as easy, but it's also not—doesn't affect the content of the photo. Just maybe the ways the colors look or how saturated they are or washed out, for example.
Placebo Effect (52:38)
Question number three: Could the placebo effect be evidence of a mind-body connection? From my understanding, a new drug need only to be proven slightly better than the placebo for it to be deemed useful. Given the proven and real effects of the placebo for a wide range of health problems, why don't doctors prescribe them? If New Agers call it spontaneous healing, the power of positive thinking or whatever, and skeptics call it the placebo effect, isn't it just a difference in labeling?
S: Well, that is a very common misconception of the placebo effect. The placebo effect is, in fact, not evidence of any unusual mind-body connection, beyond the obvious, that the mind is the body, right? I mean, the mind is a phenomenon of the biological functioning of the brain. And there is a connection between the brain and other systems in the body. For example, there is a neuroendocrine system. The—psychological stress releases hormones which can have physiological effects on your body, for example. So, beyond physiological connections between the brain and the rest of the body that are well established, there is no sort of spiritual mind-body connection implied by the placebo effect, nor is there any sort of mind-over-matter phenomenon implied by the placebo effect. What the placebo effect actually is is anything other than a physiological response to the intervention. In most cases, it's a pharmacological effect from a drug, for example. It's everything—it's all other effects in a study. And the reason why we design studies that way is that we can take the physiological effect, subtract out all the other effects, i.e. the placebo, and then we can calculate what the effect of the drug itself is, if you basically control for all the other things. But it includes lots of variables; it includes the fact that when someone's in a study, they are paying more attention to their own health. When someone's in a study, they are more compliant with their medications; they're more likely to take their medications as they should, on schedule, 'cause they think that they're under the microscope; there's a physician that's keeping close tabs on them, for example. They're just more mindful of their health. They're also getting more frequent exams by a physician. So, they're not... their health problems are not going to be potentially neglected.
There may be endocrine benefits to a positive outlook; being hopeful, for example. So, there's lots of secondary effects to being in a study, to being observed. There may be secondary effects in terms of the mood and the outlook of the individual. And those all get rolled into the placebo effect. So even without any mind-over-body effect, there is still a sizable placebo effect. The reason why we don't prescribe placebos is because, well first of all, they're unethical to do that because it's deceptive. And second, because that much of an effect is not worth it. You know, you can get—or you should get a placebo effect just from having a positive therapeutic relationship with a patient, and for doing any intervention. Having no actual effect is... not justifiable. You can't justify an intervention without any effect just because there's an intervention. Just because there's a non-specific benefit to the therapeutic relationship itself. So we'll talk about that some more in later podcasts, 'cause the idea of the placebo effect comes up quite a bit when dealing with health-related claims.
E: Could do a whole episode just on just the placebo effect.
S: We could. We could. It's very interesting. Well, that's all the time for e-mail this week. Let's move on to Science or Fiction.
Science or Fiction (56:30)
S: The Skeptics' Guide to the Universe is a production of the New England Skeptical Society. For information on this and other episodes, please visit our website at www.theness.com. You can send us questions, comments, and suggestions to podcast@theness.com. 'Theorem' is performed by Kineto and is used with permission.
References