Science Talk

Animal intelligence, Mars Rovers, Alcohol and Cardiovascular Health.

In this episode, the conclusion of a two-part interview with anthropologist Carel Van Schaik about intelligence in animals; astronomer Steven Squyres talks about the current state of the Mars Rovers Spirit and Opportunity; and cardiologist Arthur Klatsky rebuts a recent meta-study that claims that light-to-moderate alcohol consumption confers no cardiovascular health benefits. Plus, test your knowledge about some recent science in the news.

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Novartis…. Think what's possible

Welcome to Science Talk, the podcast of Scientific American magazinefor the seven days starting April 12th. I am Steve Mirsky. This week on the podcast, the conclusion of our conversation with anthropologist Carel Van Schaik on animal intelligence. Then we'll have an interview that Scientific American senior editor Wayt Gibbs recently did with astronomer Steve Squyres about the two Mars Rovers. And cardiologist Arthur Klatsky discusses a new study about the relationship between alcohol and healthy hearts. Plus, test your knowledge about some recent science in the news.

First up, Carel Van Schaik, the director of the Anthropological Institute and Museum at the University of Zurich. Last week he talked about his article in the April issue of Scientific American magazine called "Why Are Some Animals So Smart?" This week, he speculates about whether some apes could be even smarter than they get a chance to be. He spoke from his office in Switzerland.

Steve: You talk about, toward the end of the article, about the idea that the other great apes, for example gorillas and chimpanzees, probably have the potential for being much smarter than their current environment requires them to be. That's a really interesting notion. So you think that, and you do see this according to the article, when a great ape is adopted in a human family…

Schaik: Right!

Steve: … and is required to do more human things. Clearly the potential for that intelligence was there?

Schaik: Yeah! So, the idea is of course that inputs—put it like this—you are not born intelligent. You are made intelligent because of inputs. There has to be something there, some infrastructure, but if you don't fill it, if you don't develop it; and as you know, the brain is extremely plastic and it's also true for primate brains. So you need to have these inputs, social inputs enhance the signal-to-noise ratio, but of course it really depends on what those social inputs are. Great ape inputs are not human inputs. So, you might call the bootstrapping problem, in the sense that if you could, somehow—and that's what we do experimentally—increase the efficiency of those inputs, show these animals things that they would not normally see in the wild; and, of course, it turns out that with that same equipment if you prime it properly, so to speak, you can actually reach much higher levels of cognitive performance. and that's in the end. Now the expressed, realized intelligence is in the end what natural selection sees. The fact that they still have these big brains in the wild, then they do relatively for us, not so intelligent things with it, is simply because of the nature of the inputs; they can't make those inputs any better than they are. If you can, then you can achieve much greater intellectual performance with the same brain.

Steve: And of course, we are also talking about various species here who already have the potential for pretty high intelligence. You cannot teach a cat to interact the same way as you can teach a great ape to interact.

Schaik: Absolutely. And the other thing that it actually shows you is that if you would compare say an orangutan or a chimpanzee in the wild with a human hunter-gatherer, you'd see massive differences; and yet you could, now that we do these kinds of experiments, you could see that the differences are actually not as big because with the great ape brain, if properly receiving proper inputs developmentally, you can actually achieve levels that are not as far removed as the human level. And so you could see how evolution had an easier time crossing that gap than you might, you know, at least that we would have assumed before we knew this.

Steve: You get to spend a lot of time observing these animals in the wild. How much fun is that?

Schaik: (laughs)

Steve: I mean, it sounds like a lot of fun. I mean, I realize its also hard work, but …

Schaik: Well! First of all it's very hard work and some of the time, and as I said in the book, watching orangutans feed is like—or to go around their daily business—is like watching paint dry, because you know they just sit there and munch. (laughs) And they are, it's not like you know, what you see in the documentaries; [that] is, of course, hundreds of hours of observation distilled into 30 seconds of excitement.

Steve: Right! But it's nice to have a job where you can work outside.

Schaik: Absolutely. And I tell you it's never really boring because they always, every day they do something exciting that you've never seen before, and it makes you think. And you really have to, I mean, you find these things and you've plenty of time to chew on them and really think them through.

Steve: You mention in the book, that's you have a book out in addition to the article in April issue of Scientific American. What's the name of the book?

Schaik: The book is called Among Orangutans: Red Apes and the Rise of Human Culture.

Steve: And I wanted to ask you one other thing, and this is probably a naïve question. It's very different watching an orangutan from watching a chimp or gorilla.

Schaik: Right!

Steve: You definitely get the impression with all three species that somebody is in there.

Schaik: Right! Right!

Steve: But with an orangutan it's, you get the impression that[of] somebody very individual and you just get this feeling of intelligence and presence.

Schaik: Right!

Steve: And my question is, after all that, how much am I anthropomorphizing that because of the orangutan's more placid appearance?

Schaik: Right!

Steve: And how much do you think that's real?

Schaik: Well! First of all, there is nothing wrong with this kind of anthropomorphizing if it puts you onto hypothesis and testing things, right? So this is great. But orangutans have to do more than chimps and gorillas has [have to] enjoy themselves on their own because they are less gregarious, they are less social than other species. What we find of course is that there is variation in the field in the wild, different sites, you know, they are much more gregarious than others. But by and large they have to somehow amuse themselves more and that sort of maybe gave you that impression. If you now do formal cognition tests, then again now we have to really take that developmental factor into account, so it's much harder to compare existing material; but if you do compare existing materials, sort of ignore the developmental component, then chimps and orangutans come up very, very similar. So the idea that orangutans are somehow more philosophical, you know, more deeper thinkers and you think of [that] Rodin statue, there that['s] probably not quite right.

Steve: That's probably an assumption based on their contemplative appearance.

Schaik: Exactly! Yeah!

Steve: It's fascinating. Dr. Van Schaik thanks very much for talking to us.

Schaik: Sure.

Steve: Carel Van Schaik's article "Why are Some Animals So Smart" is in the April issue of Scientific American magazine, and it's available free at our Web site,

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

Story number 1: A paper came out last week showing that 9,000 years ago people were doing sophisticated dentistry that included drilling fine holes in teeth.

Story number 2: Archivists working on the personal papers of President Theodore Roosevelt found out that he applied for a patent for his special vented wooden rack for drying rubber boots and was rejected.

Story number 3: Researchers report that the bacterium Caulobacter crescentus produces nature's strongest known glue—about four times stronger than commercial superglue.

And Story number 4: A Canadian researcher who wanted to study whether the so-called intelligent design movement in the U.S. might be affecting acceptance of evolution in Canada was denied funding because a Canadian federal agency wasn't sure there was enough evidence for evolution in the first place.

We'll be back with the answer. But first Cornell University astronomer Steven Squyres is the principal investigator for the Mars Rovers science instruments. The rovers, Spirit and Opportunity, are way past warranty. They landed in January of 2004 and were expected to work for a few months, but we are still ticking when Scientific American senior writer Wayt Gibbs caught up with Squyres a few weeks ago. Here are portions of that interview, which took place in a relatively quiet corner of the pressroom at a conference in San Jose, California.

Gibbs: You mentioned that one of the Rovers is now at this formation called Home Plate.

Squyres: Yeah!

Gibbs: What do you hope to learn?

Squyres: What it is, how it formed. It's a plateau; it's a raised plateau about two meters high, about 80 or 90 meters across from orbit and from the summit of Husband Hill. It's notably light tone, I mean, it's got a higher albedo, it's lighter than everything around it. And then when you get up to it, what you find is that it's very finely, very intricately layered. The layering changes as you go up-section, meaning there is a stack of layers two meters high then at the bottom the grains are large, they are sort of coarse, you know, [a] few millimeters in size and scattered around in coarse grains; and then as you go upwards you grained, it grades into much finer grain stuffs; the sand grains so effectively. The upper portion in particular does show some—what's called—cross bedding. We have beds that kind of lie in an angle to one another. There are a number of different ways in which that kind of cross bedding can be made and so it's not necessarily diagnostically formation process. Right now we've got a number of open hypotheses for how this stuff might have formed. You can make layered rock like that by depositing things in water; you could make it by depositing things in air—so, wind blowing things around—and you certainly can make it as a result of something like a volcanic explosion, an ash flow sort of a process. To differentiate among these different hypotheses we need to take more observations of, you know, in detail. There are microscopic images that shows the grain size, how round they are, how coarse are they [are], get in detail what the rocks are made of—this is all information that we're in the process of gathering now, so it is kind of an ongoing investigation. Right now we're trying to keep our minds open to just gather the data.

Gibbs: Is it the kind of thing where you expect to learn something just about this rock or [do] you actually hope to learn something about Mars in general?

Squyres: Well! I mean everything that you know about Mars tells you something about Mars. It's—the question is how broad we are globally—can you extend the knowledge that you gained? And that depends on the nature of it. A lot of us suspect that this might be some kind of explosive volcanic material. What would happen if, say, you had lava that was being erupted or ejected and it came into contact with the subsurface body of water, okay, and all of a sudden that stuff flashes and the steam—KABOOM, you know, and then PSHSHEWW, it settles out; so we might be dealing with something like that. This is an unfolding mystery that's changing day to day right now.

Gibbs: The other rover is on its way, you said, to Victoria Crater, a very large and very promising looking destination. If things go well, when will you expect to arrive?

Squyres: Yeah! I have absolutely no idea. The reason I can't project that is because we don't know anything really about the terrain we'll be driving through. It's Mars, I mean, I have no idea what we're going to find.

Gibbs: You got that big break when the wind gusts cleared the sand after the soil.

Squyres: Yeah! We have actually got several events like that on both the spacecrafts.

Gibbs: Is it your guess that that will be a recurring event that they will greatly extend along the lines of things most indefinitely?

Squyres: It's hard to say. On Opportunity we have seen a series of small cleaning events take place over almost the whole machine, so that, you know, little bits of wind. Opportunity, I don't think will not work, but I think it's very likely that Opportunity will not die as a result of dust and soil pounds. Opportunity is very close to the equator, so it has lost solar power. Opportunity, we had seemed to get these little cleaning events every so often and so I think Opportunity could last for quite a long time. Spirit is a different story. It's different for two reasons. One is that Spirit is at a higher latitude, it's at 16-degree south latitude; and so what that means is that the winters are much more severe for the Spirit than they are for Opportunity. And the other is that [with] Spirit, we're in the mountains, we're in this [these] very complex mountains geographically; and when you are up on a ridge crest and you are up on a summit, which is where all our cleaning events took place was on ridge crests and summit; then you are exposed to the wind and you get cleaned off. Right now, we're down in a valley, we we're down in a valley for a good reason. We went there because that's where Home Plate is and Home Plate is probably the most interesting thing that we found since we landed, but we are kind of sheltered from the wind where we are right now. So Spirit, it's getting tough. What we are trying to do with Spirit to survive this coming Martian winter is this very same thing we did last Martian winter; if you looked carefully at the route that we took, when we ran up Husband Hill, we didn't do a straight shot, we didn't go right up the ridge; instead we drove around on the north face, and what that did is you know, we are in the southern hemisphere, you drive on the north facing slope, it tilts your solar arrays towards the sun…

Gibbs: Right!

Squyres: … and we get about 15 to 20 degrees of tilt that way, and that gave us a lot more electrical power to survive the winter. I think we would just have to hibernate all winter along if we hadn't had that slope, so …

Gibbs: It is designed to have sort of a hibernation mode or …

Squyres: No!

Gibbs: No!

Squyres: No. It's something we would [ha]ve to sort of invent; (laughs) we would [ha]ve to just figure out how to do it. But what we are trying to do right now is once we rap up Home Plate—and we don't have much time at Home Plate, we only go[e]t a few weeks there—We're going to try sprint off to the south and find a hill that will face the arrays towards the north again where it'll be a place—sort of a safe winter haven where we can try to spend another Martian winter.

Steve: Now the day[s] since that interview, one of the six wheels on Spirit stopped working, but the engineers back here on Earth have been working on that problem and I got [an] e-mail on April 10th from Squyres that read, "We've spent the last several weeks learning to drive with five wheels and are finally getting the hang of it, and as of today"—and again that's April 10th—"Spirit has now reached what looks like a safe winter haven on a feature called Low Ridge. In our current location, we are tilted at 11.5 degrees toward the north, which has substantially increased the power output from the solar arrays, so we are feeling pretty good about this." That was Squyres on April 10th. You can follow the slow-motion drama at the Mars Rovers Web site; just go to—j-p-l for Jet Propulsion Laboratory—and once you're there, hit the link for the rovers. We'll be right back.

Male voice: Novartis—committed to making innovative medicines for a world of patients and their families, online at

Novartis…. Think what's possible.

Steve: Now it's time to see which story was TOTALL…….Y BOGUS. Let's review the four stories.

Story number 1: 9,000-year-old dentistry.

Story number 2: Teddy Roosevelt was denied a patent.

Story number 3: A bacterium produces the strongest known glue.

And story number 4: A Canadian Federal Agency denied funding a study of attitudes about evolution because they were unsure about evolution.

Time is up.

Story number 1: The ancient dentistry story is true. The April 6th issue of the journal Nature published the discovery of literally Flintstone dentistry. Rotating flint points were probably the drills. The journal article describes 11 drilled molar crowns described in a Neolithic graveyard in Pakistan that dates from 7,500 to 9,000 years ago. Drilling could have been aesthetic, if not anesthetic—ouch! You could read Kate Wong's coverage at

And story number 3 is true. Scientists writing in the April 11th issue of the Proceedings of the National Academy of Sciences report that Caulobacter crescentus produces the strongest glue known. The glue works on wet surfaces, so there is hope that it could be developed into a surgical adhesive.

Story number 4 about the Canadian evolution snafu is true. Brian Alters is the director of McGill University's Evolution Education Research Center and he wanted to study whether the intelligent design campaign in the U.S. is affecting attitudes in Canada, but the Federal Funding Agency called the Social Sciences and Humanities Research Council denied his grant saying Alters had not supplied "adequate justification for the assumption in his proposal that the theory of evolution and not intelligent design theory was correct." Alters said, "It was ironic proof that intelligent design may indeed be making in-roads north of the border." Intelligent design: helping to put the Dove[r] in Canada. Oh! And before you start typing your upset e-mail about what I just said, you have to promise to read all 139 pages of Judge John Jones' decision in the Dover case.

All of which means that the story about Teddy Roosevelt and his patent application for a wooden rack to dry rubber shoes is TOTALL…….Y BOGUS. Also bogus are reports of any Dutch researcher's creation of a rubber rack for drying wooden shoes.

Next up, Arthur Klatsky. He is a cardiologist at the Kaiser Permanente Medical Center in Oakland, California, and for three decades, he has been the leading researcher studying the effect of alcohol consumption on the cardiovascular system; and I was the editor of his February 2003 Scientific American article called, "Drink to Your Health". A new study came out last week—what's called a metastudy that looked at dozens of previous studies—now most of these older studies said that light-to-moderate drinkers were in better cardiovascular shape than people who didn't drink at all, but this new study said that the older studies have made a big mistake. They had included former drinkers, some of who might be in pretty bad shape with the nondrinkers. So the new study said that light drinkers got no benefit over nondrinkers. I wanted to get Klatsky's take on all this, so I called him at his home in Orinda, California.

Steve: Dr. Klatsky thanks for being with us today.

Klatsky: It's a pleasure to be with you Steve and to hear from you again.

Steve: You have been in the news a little bit. There is this new study that was in the online journal Addiction Research and Theory. They say in this new study that the belief previously from studies such as many of yours that moderate alcohol consumption actually meant that you had a lower risk of cardiovascular disease than abstainers, they say that that's not true and abstainers and moderate drinkers have the same risk. So what's going on with that whole business?

Klatsky: Well Steve, it's a little bit complicated, but let me make a couple of background points. [In] the first place, it is well known that we don't have any experiments in this area. We're dealing only with what are called observational studies, where people's habits are recorded and then things that happen to those people over the following number of years are noted and relationships are observed. And in these studies, it's customary to control for things that might give an indirect result, and more support, for example, is cigarette smoking. Point number two is that this particular meta-analysis dealt with total mortality and with coronary heart disease mortality. Now coronary heart disease is, of course, the commonest kind of heart disease [and], as you know, is the condition for which light-to-moderate drinking seems to be the most beneficial; and the lower mortality of light-to-moderate drinkers is in a large number of studies, many dozens of studies; they do [due] primarily to lower death rate for coronary heart disease, which causes heart attacks; sometimes it causes sudden death without any preceding warning. Now the evidence that mild-to-moderate drinking reduces the risk of coronary heart disease, both fatal and nonfatal, is very strong. Not only are there a lot of good, well-performed observational studies that show that, that there is a lot good plausible biological evidence for mechanisms by which alcohol might prevent coronary heart disease. Okay that's the background. The largest problem in my mind with their analysis is curiously because [curiously] they talked about misclassification. They seriously misclassified a lot of the studies. No! I can't speak about all of the ones that they looked at, but I know that they misclassified our class of Permanente studies because we've been working with the data’s that clearly separates past drinkers and the less-than-one-per-month drinkers from lifelong abstainers, that we have published two or three studies that clearly show that with these groups separated that light-to-moderate drinkers have lower coronary mortality or total mortality or both; classified studies from the point of view of not including some of the studies that should have been included as free of the errors, that's one problem.

Steve: Okay, so they did not include studies that really should have been included in the meta-analysis.

Klatsky: On the other hand some of the studies that they included as free of errors should not have been included at all; studies of the young man, one of those few [of] young African American m[e]an in the urban setting, and it's well know that there is not likely to be any evidence relevant to cardiovascular mortality in men in their twenties to thirties. Well I don't think that their analysis really seriously undermines the large body of evidence strongly, suggest on the basis of observational data only, or to point out that we don't have the Holy Grail. We don't have the randomized control trial. However, their claim is that even those observational reports are flawed; I don't think they approve that in this particular analysis.

Steve: Can you talk just a little bit about what the optimal study would look like?

Klatsky: The optimal study would be study of a large enough number of people to see a difference over a period of time and it would have to be years, between people who were light drinkers and people who were abstainers from alcohol. The way that it would have to be done would be that people would be selected for the study as being willing to be randomized, strictly by chance into a light drinking group and an obsoletes group and they would have to adhere to whatever they were randomized to for enough years to complete the analysis. This would be obviously very difficult to do. But the ideal study for mortality would have to involve thousands of thousands of people followed long enough to see the difference between these groups.

Steve: Okay. So for now, you are quite comfortable maintaining the assertion that based on the available data, it looks like light to moderate alcohol consumption does confer some kind of benefit in terms of cardiovascular health.

Klatsky: I think the evidence is quite compelling. There is no obvious indirect explanation and attempts to find one have not been fruitful. The finding is consistent in men and women in various ethnic groups in different parts of the world and any indirect explanation would have to apply to all of those groups, so I think the simplest explanation [is] that alcohol, light-to-moderate drinking, is really protective against coronary heart disease, and [it] is the likely correct one.

Steve: Dr. Klatsky thanks very much.

Klatsky: Nice talking to you.

Steve: You can find Arthur Klatsky's February 2003 Scientific American article, "Drink to Your Health" in our digital archive,

Interested in the inner workings of the human brain? Scientific American Mind magazine brings you breakthroughs in psychology, neuroscience and more. For a free preview, visit,

Well that's it for this edition of the Scientific American podcast. Our e-mail address is; and also remember that science news is updated daily on the Scientific American Web site, For Science Talk, the podcast of Scientific American magazine, I am Steve Mirsky. Thanks for clicking on us.

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