Podcast Transcription

Steve: Welcome to Science Talk, the weekly Podcast of Scientific American posted on May 1st, 2009. I'm Steve Mirsky. This week on the podcast, we look at the new May issue of Scientific American with Editor in Chief John Rennie, and we'll test your knowledge about some recent science in the news. But first, the big story this week of course, swine flu. Scientific American editor Christine Soares is our staff flu expert. We spoke in the magazine's library.

Steve: Christine, the swine flu story is moving fast. We're talking on Tuesday afternoon, by the time people listen to this, things may have fundamentally changed, so I am going to assume that people will follow it with all the technology available: radio, TV, and especially on their computers, just seeing developments, practically in real-time. So let's talk about what you might not get in that real-time self immersion that people might do. So, for example, we're hearing death toll numbers, but the death toll numbers usually don't come in any kind of a context like what's the total number of infections.

Soares: Well exactly. That is the key bit of information as in fact some of the deaths have not been confirmed as swine flu cases, so it's impossible to draw any conclusion about how lethal this flu is from the numbers we have now. But that is exactly what the WHO and others are investigating, the extent of infection, who actually has swine flu, who had regular flu, other respiratory infections, other causes of death. So that's a big question mark right now.

Steve: So when you hear a number, for example, a 150 dead out of Mexico, which I heard something close to that on the radio this morning—it's not really giving you much information.

Soares: Well, no, because, again, those people may not all have been confirmed cases of swine flu and, again, those are just the most serious cases that showed up in hospitals; so this virus could well have been spreading much more widely and causing mild illness in the majority of people. So what we are seeing is just the tip of the iceberg who got really, really sick.

Steve: So what are the possible scenarios, I mean, a week from now or two weeks from now, how could things have gotten worse or how could things have gotten better?

Soares: Well it's very hard to tell. I mean, the numbers are rising very, very fast as people now start looking for this and testing it now. People who show up with respiratory illnesses, they are being tested. And lo and behold they are finding a lot more infections than anybody realized were there, and that is likely to continue. And, I mean, one thing to bear in mind is this flu season is about to wind down in the northern hemisphere, so perhaps this will actually just start winding down, but it's about to pick up in the Southern hemisphere, so.

Steve: So right now we've been seeing things moving north and may[be] we will start to see things moving south.

Soares: Perhaps, yeah. I mean, one thing I was thinking was looking at the number of students, college students and younger students, that were infected may now wonder what the role of spring break was in all of this.

Steve: An interesting question; it could be the spring break flu.

Soares: Well the spring break travelers, in any case, bringing it home.

Steve: Is it unusual to see an outbreak this late in the flu season? I mean, you know it's 90 degrees in New York today and we don't think of flu as being a warm weather sickness.

Soares: No, I think actually the weather is the aberration and the flu season is actually year- around in tropical zones, that's seasonal in the more temperate zones. So, no, April are still fair game for flu.

Steve: And could we see this same strain of flu just crop up again in the fall when, you know, typical flu season begins again?

Soares: Certainly. You know either it will die down completely and disappear rather the way the SARS did, or, yes we'll see it again in the fall, we will see after the summer in the Southern Hemisphere. If you remember, too, that H1N1 is originally a human virus, it was given to pigs by us, and it still circulates, a different variant of it obviously, still circulates in people. So if this virus meets up with the human H1N1 that's a little more transmissible, and it can really just become part of the seasonal flu varieties that we already have circulating everywhere.

Steve: This is H1N1 as opposed to, I mean, a few years ago we were all worried about the bird flu, which is H5N1. What does that actually mean?

Soares: Well the H and the N refer to two proteins on the virus surface that help it infect cells and also spread from cell to cell once they are in the lungs, in case of birds in the gut, as well. So it's just a gross designation [of] a type of virus and then within each category, H1N1 for example, there's a lot of subtle variations that can happen in the genes of the virus that make them distinct. And so you can identify the certain strains that are circulating in people, the ones that are more commonly circulating in pigs and this is an H1N1 virus that has been known to circulate in pigs and seems to have picked up little bits and pieces from other H1N1 viruses that circulate in pigs elsewhere.

Steve: The Spanish flu of 1918–1919 was an H1N1 but that does not mean that this is going to be another Spanish flu.

Soares: Well, yes and no. It was an H1N1 because it was the first one identified and given this designation, so it got number one, and yes, that's the very same H1N1 that caused the pandemic that after a couple of years settled down to become the circulating flu in humans until the 1950s, when the next pandemic strain emerged; and sometime during that period humans actually gave this H1N1 to pigs. So H1N1 in itself is a, you know, broad category of viruses that circulate in humans, even now; they are not as fearsome as the original strain when it first emerged.

Steve: But the fact that it's an H1N1 has the public health authorities really keeping an eye on it.

Soares: I think probably because it could more recently recombine with a human flu strain. I mean, I think the fact that it's not H5N1 is probably what's making me happier, but I don't think, the fact that's an H1N1 is a reason public health authorities would be more or less worried. But it is something to bear in mind that this is a strain that's been around a long, long time in humans and in pigs, so it's not as completely novel and unseen, as say one of these avian strains [would have been].

Steve: So everybody should wash their hands often.

Soares: Yes.

Steve: You know, just try to keep away from other people.

Soares: Indeed. I mean remember that the 1957 and '68 pandemics were actually quite mild in terms of illness. They were pandemics because they were new strains and because a larger number of people got infected, but as far as flu they were kind of regular garden variety flu, and hopefully we may have dodged a bullet and this one and will be like that, too.

Steve: Check out our ongoing coverage of the swine flu, which I[ha]s already mutated semantically to become the H1N1 flu at www.SciAm.com. Now that May is here, it's time for Editor in Chief John Rennie to visit the podcast to talk about the latest issue. We spoke in the magazine's library.

Steve: Hi John, it's that time again.

Rennie: Indeed it is. Hello.

Steve: Hi. The May issue has a really interesting coverage, [it's] sort of a hybrid of a human and a chimp.

Rennie: Yes.

Steve: And that's not an old TV show from the '60s. And the title is "What Makes Us Human".

Rennie: Right, "What Makes Us Human"—at least in a genetic sense. This cover story is a look at what information has been coming out of direct genetic comparisons of the chimpanzee genome and the human genome. So we know that chimpanzees represent our closest living animal relatives, and they and their human line, sort of, parted company about six million years ago. So the question really is, you know, what kinds of genetic changes really would have cropped up since then that have helped to make human beings what they are?

Steve: What's really interesting is we are all always hearing about, you know, chimps and humans are 98.7 percent the same, 99 percent the same, whatever the number happens to be depending on how you do your sequences.

Rennie: Right.

Steve: But what's really interesting is that 1 percent difference; that's really important.

Rennie: Right.

Steve: It's not just, "Oh, we're so close," it's, "Yeah, we're so close genetically but the differences are actually immense"; and I can prove that [to] you, because there ain't no chimps doing podcasts—don't go there. (laughs) So now the thing in the article that I had never heard before that talks about how many sequences, for example, in a chicken and a chimp are much, much closer than in us and a chimp and that's really fascinating.

Rennie: Right, yeah, actually it is pretty astonishing that in many respects during these past 6 million years which are just, you know, a tiny piece of animal evolution within those portions of the genome where you're seeing differences pop up. You're looking at this kind of astonishingly accelerated rate of a change. As you said it is an extremely small number of differences that you find genetically between humans and chimps, but it is an extremely important one, and what seems to make it so important is that a lot o these differences seem to affect what are in effect regulatory sequences. They are in some cases not the things that actually distinguish the types of proteins that we make. We and chimpanzees are basically made of almost exactly the same stuff; its how it's all put together. And so what we're seeing is that these very, very tiny tweaks in the instruction set, basically, for how to build a human body are profoundly influential. And we really see that that's why you do look at this extraordinary difference between us and chimpanzees [in], for example, our mental capabilities and the rest.

Steve: And that's what you would expect. You would expect to see it in the regulatory sequences because then the effect of a small change can be huge because you are affecting the timing and maybe the sequence of events in development. And so it's like, you know, if you have two planes starting off on a very similar trajectory but it's not quite exactly the same and, you know, come back in three hours and they are thousands of miles apart.

Rennie: Right, right. It shows in a lot of ways how, what I think was a kind of simple minded approach that people took to what we might find in the genetic information in the past. I don't say simple minded to be critical of anybody, you know; the obvious approach that you would look at the number of differences of proteins and that would be the key to what made things so different. And protein differences are very important but, in fact, it is the instruction set that seems to be that much more important which is why we are finding that a lot of the most significant differences aren't one's in the stretches of DNA that encode the protein information, they are in fact what are sometimes referred to as junk DNA, as the pieces of information that no one knew what they were doing in the past.

Steve: And one of them that's talked about [in] the article is HAR1, and it seems that is related to the development of the cerebral cortex, which is obviously one of the places where chimps and us have a lot of differences. And another one is the FOXP2 gene which winds up having a role in how you can work your mouth to speak.

Rennie: Right, which is why we seem to have the kind of verbal abilities that we have that you don't see any place else in the animal kingdom. Yeah, what's actually sort of gratifying when you look at some of the differences that seemed to be showing up is that that a lot of these most significant tiny differences in the genomes between the humans and the chimps aren't exactly where you would think they would be in terms of their effects. That is, you are seeing a disproportionate number of these showing up in things that I have to do with the structure of our brains or portions of our ability to speak, things having to do with our digestion, because our dietary habits have changes quite a lot over time. So it really, you know, it makes sense, it confirms what you would expect if you were comparing how does the organism of the human being differ from the organism of the chimpanzee.

Steve: We have become so different from chimps and so incredibly, wildly successful that we can do all kinds of amazingly creative things like steal information from each other, and we have an article by Wayt Gibbs, "How to Steal Secrets" without even using a computer network.

Rennie: Right.

Steve: It's like the old story of the guys playing poker and somebody is wearing glasses, and you can see the reflection of the cards that guy is holding in his glasses—but on a much, much more sophisticated level.

Rennie: Actually, sort of, in some way surprisingly almost not that too much more sophisticated level. I mean the astonishing thing is that this kind of side-channel hacking that Wayt Gibbs is writing about is pretty much exactly that. They point out that somebody with a $500 dollar telescope at this point can use this to peer at the reflections in glasses or even just pick up reflections off the surface of your eye in many cases. Yeah, it's astonishing, that these new kinds of things that are going on, and what's amazing and ominous about it is that this kind of side channel hacking...

Steve: And that's the term of hard-disk, side-channel hacking.

Rennie: Right. Because traditional hacking is based on the network itself; the idea of that is that you are looking for someone who is finding [a] way to go in [through] the orthodox ways of accessing the computer information. Side-channel hacking is completely side stepping all of the usual kinds of defenses that you could build up, because those defenses are established basically stopping one computer from serendipitously tapping into information in another computer. In this case, you're doing the equivalent of hacking the room. You're picking up reflections off surfaces. You're taking vibrations from a printer or the sound of a key board; and a lot of these kinds of information are the sorts of things that we would normally think, "Well, they are basically indistinguishable. I mean, does it really seem very different if I am pressing the E key on my keyboard from the F key?" Well, in fact, with a certain level of highly sophisticated data processing, that is now possible to bring to the problem. You can often start to draw conclusions about what somebody is typing just by the sound of the clatter of their keyboard.

Steve: And there are people who are out there, instead of hacking into the actual electrons that are flowing, and reading what you are up to that way, they are in an office building a block away with the telescope looking through the office window of somebody else and just looking at the computer screen to read what they are up to.

Rennie: Right or looking at reflections of that computer screen off other surfaces in the room.

Steve: [A ] painting, the glass cover.

Rennie: Right, now obviously this is not a highly widespread form of hacking at this point, but what concerns at least a lot of data security experts is that the technologies involved are relatively easy to get hold of and...

Steve: ...Cheap.

Rennie: ..And cheap—and that it's almost impossible in usual terms to try to insulate rooms well enough that you can stop this kind of thing.

Steve: There's information leaking out of every room as long as the curtain is not completely down, and even if the curtain is down, you can measure the vibration of the curtains somehow.

Rennie: Yeah, I mean it's if you have a sensitive enough equipment, it's astonishing all the kinds of information you can deduce back out of that, if you have enough sophisticated computer processing to backup the kind of analysis you want to do.

Steve: And again this is not a hugely widespread problem right now, but this article is warning about what kind of problem it could become and what kind of safeguards need to be put in place.

Rennie: That's right.

Steve: And again, we are such a sophisticated form of chimp, if you will, that we have reached the point where we might even run out of food for ourselves.

Rennie: Yes, there is no question that people have known for a long time our food supply is obviously pressed by a lot of different problems. Obviously, the numbers of people that it is trying to feed; problems of shortages of water, disappearing quantities of top soil on which we have to grow these different crops; and, of course, now climate change, which also is throwing a lot of randomness or bad factors into our attempts to grow enough food for everybody. So in the May issue, Lester Brown of the Earth Policy Institute, he writes an essay in which he raises sort of the specter that potentially, in the decades to come, that if we are not careful, that these problems with maintaining a sufficient food supply could get bad enough that it actually would threaten the state of civilization globally; that it just could cause widespread chaos, cause a large number of failed states and trigger [an] enormous number of problems down the line.

Steve: And he's not just [a] Chicken Little running around, [crying the] sky is falling?

Rennie: Well, you know, there is no question Lester Brown has been sounding some level of alarm about this for number of decades. He has, in fact. has seen several of these kinds of problems coming a long way off, so that still there are people who certainly do think that maybe he has sounded this particular alarm [a] few times to many. Nevertheless he is arguing that, in fact, what we are now seeing is the realization of a lot of the particular problems that he has been pointing to for several decades and that we really do need to take the appropriate steps to be able to intervene in this. The good news is though that I think he does feel that it is still possible to take some kinds of actions to respond to problems of climate change, to do a better job of trying to conserve top soil, to try to address the problems of water scarcity all over the world and so forth; that we can actually head off a lot of these problems. He is just arguing that it would be a mistake to sort of maintain business as usual, that we need to go to a kind of plan B.

Steve: The top soil—what about the air we breathe? We have another article "The Planetary Air Leak", apparently we are losing the atmosphere.

Rennie: Well, no Steve, don't panic. Yes, the earth's atmosphere is leaking away very, very, very, slowly. This is a kind of phenomenon that happens to all planets and all moons with atmospheres. So over time it's almost inevitable for them to start to lose a lot of their atmosphere. Sometimes they can gather atmosphere too. But on balance most planets start to lose some amount of their atmosphere over time. They lose their atmosphere partly because the temperature of the sun, of course, makes some of the gases in the atmosphere very warm. and some of the atoms of molecules then reach escape velocity and fly away from the planets. But a variety of other circumstances, for example, the impact of big asteroids, can blast a lot of atmosphere away and a lot of other more subtle phenomena can happen that can also sort of draw the atmosphere away. So this is always been happening on the Earth, and, in fact, it has happened on the Venus and on Mars; and. in fact, a lot of—when we look at these worlds, a lot of these same kinds of phenomena had been taking place, sometime reaching extremely different ends. It may seem surprising to people, but you can look at something like Mars, which has a very thin atmosphere, and you can look at something like Venus which we tend to think of as sort of having this rather heavy, clouded atmosphere, which [is] hellishly warm because of runaway greenhouse effect, and on both of those planets you are seeing this phenomenon of the atmosphere leaking away, is actually what directly has led to those very different outcomes for those planets; the specifics of what happened as the atmosphere started to go in each case [made] all the difference.

Steve: Venus lost all the good stuff and Mars lost all the stuff or almost.

Rennie: Pretty much, I mean that's basically, that's right. In the case of Venus, you're seeing that the effects that were going on were drawing away the oxygen disproportionately and leaving the planet enriched with carbon dioxide in it's atmosphere. And in the case of Mars, we are just looking at a lot of phenomena that were taking away a lot of the atmosphere in general and leaving the oxygen, so that it could start to oxidize a lot of the surface of the planet.

Steve: That's why it's red.

Rennie: Yes it is.

Steve: Where do you gather new atmosphere from? [Do] you go to the atmosphere store?

Rennie: Planets get, [a] lot of the atmospheres that they have tend to come from fairly early in their formation, a lot of the atmosphere forms as a result of gases that either leak out of their interior or that, sort of, evolve from chemical processes and [then]that they accumulate. But you can also have you know comets or other sorts of bodies can slam into a young planet and can deposit a lot of atmosphere that way.

Steve: So all we need is another major asteroid collision to increase our supply of atmosphere.

Rennie: Yeah, on balance we would probably be a lot happier if you could find a way to go to the atmosphere store. But I think I can only emphasize we don't actually need more atmosphere here on [Earth].

Steve: Okay and, of course ...

Rennie: Maybe in romantic little French restaurants, I don't know.

Steve: Well, I was going to say you know, the restaurant on the moon, of course you know about [that].

Rennie: I was not aware of the restaurant on the moon.

Steve: Right. The food is great...

Rennie: ...No atmosphere. Oh, good heavens.

Steve: So...

Rennie: Walked right into that.

Steve: [A] lot of other interesting things in the May issue, I just wanted to share with you, I know that you have seen this before, but you haven't looked [at] it in some weeks: our popular "50, 100 and 150 Years Ago in Scientific American" page; and in May of 1859, we wrote, "An ingenious individual of Liskeard, Cornwall, England, has for sometime in the past has been exhibiting himself on a dress composed from top to toe of rat skins, which he has been collecting for three years and a half. The dress was made entirely by himself. It consists of hat, neckerchief, coat, waistcoat, trousers, tippet"—whatever that is—"gaiters and shoes. The number of rats required to complete this suite was..."

Rennie: ...670.

Steve: "...670"—anybody out there [who] had 670 in the pool, you win—and the individual when thus dressed appears exactly like that of the Esquimaux." I believe that is spelled E-S-Q-U-I-M-A-U-X.

Rennie: We were a more refined people in those days.

Steve: Yes. Described in the travels of Parry and Ross.

Rennie: Now.

Steve: There you go, anybody who was wondering how many rats it would take to...

Rennie: Steve, there is a question I have, and I mean it [is] an astonishing enough story that way to hear about the tailoring of this suit made of rat skins. But what I don't understand is how do you manage to have that on today?

Steve: I have two cats.

Rennie: Ah....

Steve: Need I say more?

Rennie: Well [that] would do it.

Steve: So now you know how many holes it takes to fill the Albert Hall, I mean rat skins it takes to make a coat.

(music)

Now it's time to play TOTALL....... Y BOGUS. Here are four science stories; only three are true. See if you know which story is TOTALL....... Y BOGUS.

Story number 1: A tree heretofore unknown to science covers about 8,000 square kilometers in Ethiopia.

Story number 2: House of Representatives minority leader John Boehner thinks that because we exhale carbon dioxide it can't be harmful to the environment.

Story number 3: All bats regardless of size and type of perch, land on the perch the same way.

And story number 4: A small study of radiologists found that those who listen to classical music as they examined images made better diagnoses.

By the way, back on the March 19th podcast during a discussion of malaria I referred to plasmodium bacteria. That was very wrong of me, the parasite that causes malaria is a protozoan and not a bacterium. As for this week's TOTALL....... Y BOGUS, time is up.

Story number 1 is true. Eight thousand square kilometers of Ethiopia are dominated by millions of Acacia fumosa trees, which scientists had never before identified. The find was reported in the journal Science. The area's inaccessibility, to which political unrest contributes, has kept scientists away. Some 300 species of flowering plants from Africa alone are described in the literature for the first time each year.

Story number 2 is true. Representative Boehner made his remarkably error-filled comments about carbon emissions in a discussion with George Stephanopoulos on the April 19th episode of ABC's This Week.

George: What is the Republican plan to deal with carbon emissions, which every major scientific organization has said is contributing to climate change?

Boehner: George, the idea of that carbon dioxide is a carcinogen that is harmful to our environment is almost comical. Every time we exhale, we exhale carbon dioxide. Every cow in the world, you know, when they do what they do, you have got more carbon dioxide. And so I think it is clear we have had climate change over the last 100 years.

George: So you don't believe greenhouse gases are a problem and are creating climate change?

Boehner: Listen, it's clear we've had change in our climate; the question is how much does man have to do with it and what is the proper way to deal with this.

Story number 4 is true. Listening to classical music improved radiologists' diagnostic efficiency [and] accuracy. The preliminary study included eight radiologists and was presented April 27th at the annual meeting of the American Roentgen Ray Society.

All of which means that story number 3, about all bat species landing on their perch in the same way is TOTALL....... Y BOGUS. Well they all hang upside down, but a Brown University study of three species of bats in the journal Experimental Biology found at least two completely different methods of landing in that upside down position. A Southeast Asian tree-roosting bat executes a half back flip to land with its back legs and thumbs hitting the landing site simultaneously, a four point landing. But two cave roosting bats from the Americas come in vertically than [yaw hard] right or left into a cart wheel and grab the landing pad with just the back legs. With 1,200 species of bats worldwide, there's plenty more slow-motion camera work left to do for aspiring doctoral students.

(music)

Well that's it for this edition of Scientific American's Science Talk. Check out http://www.SciAm.com for the latest science news, including the latest news about the flu, such as our list of five ways to protect yourself and others from it. For Science Talk, I'm Steve Mirsky. Thanks for clicking on us.

Scientific American editor Christine Soares discusses the swine flu situation and Editor in Chief John Rennie talks about the May issue--topics include the specific genetic differences between humans and chimps, side-channel hacking, food shortages, and our leaky atmosphere. Plus, we'll test your knowledge of some recent science in the news.