Science Magazine Podcast Transcript, 14 August 2009 http://podcasts.aaas.org/science_podcast/SciencePodcast_090814.mp3

Music Host Robert Frederick Hello and welcome to the Science Magazine Podcast for August 14th, 2009. I'm Robert Frederick. This week: monkeys prefer to be around people who imitate them; the timing of when humans first used fire as an engineering tool; and improving energy efficiency. All this and more, plus a wrap-up of some of the latest science newsincluding a story about whether clouds come from outer spacefrom our online daily news site, ScienceNOW. Promo Support for the Science Magazine Podcast is provided by AAAS: the American Association for the Advancement of Science, Advancing Science, Engineering, and Innovation throughout the World for the Benefit of All People. AAASthe Science Societyat www.aaas.org. Music ends Host Robert Frederick Scientists already know that people subconsciously imitate each other to promote affiliation. And now, in this week's Science, researchers report that capuchin monkeys appear to, too, spending more time with people who imitate them than with those who don't. The finding suggests that such behavior might have provided an evolutionary advantage by fostering increased social interaction. The research may also help scientists better understand autism and other disorders in which people have trouble imitating others. Science's Preyanka Makadia has more. Feature Writer Preyanka Makadia The experiment was designed to see if monkeys, like humans, subconsciously prefer individuals who imitate them. The researchers began by giving each monkey a plastic ball with food inside that the monkeys could see and smell through little holes in the ball. One person observed the animal's reaction to the ball and mimicked it, pounding the ball on the ground, poking at the holes, or mouthing the ball just like the monkey. At the same time, another observer reacted by consciously not imitating the monkey. Annika Paukner, a psychologist at the National Institute of Child Health and Human Development and lead author of the paper, says that the researchers had three ways to tell if the monkeys preferred the people who were imitating them. Interviewee Annika Paukner The first one was simple: a visual preference. So, they look longer at the person that imitates them rather than the person that doesn't imitate them. And then we had two different experiments. In one experiment we measured proximity. So, with monkeys,

you can measure how well monkeys get on with each otherhow affiliative they arejust by looking at how much time they spend together. So, we measured how much time does a monkey want to spend in front of a human before and after the imitation. And we found after imitation, they increase the amount of time that they spend with the imitator relative to the non-imitator. Feature Writer Preyanka Makadia Researchers also measured whether the monkeys preferred the imitator over the non-imitator by conducting what scientists call a "token exchange." Again, Annika Paukner: Interviewee Annika Paukner How that works is, we trained our monkeys, and if you give them a small metal token, they would give it back to us for a little food reward. So its an interaction you know you give something to the monkey, and he gives it back to you. So, we tested, "Do these amount interactions increase? Do they prefer the imitator for these interactions rather than the non-imitator?" And again, we found, yes, they prefer to go to the imitator to do the exchange rather than the non-imitator. Feature Writer Preyanka Makadia Previous studies have shown that humans tend to imitate others. That leads them to like others more, empathize with them, and exhibit greater generosity. Tanya Chartrand is a human behaviorist at Duke University. Interviewee Tanya Chartrand But with the monkeys, theyre not consciously thinking of this, presumably, so it's suggesting that it is more hard-wired, and as a result of this being kind of a hard-wired connection between mimicry and affiliation, suggesting that maybe has served this evolutionary function for us and for primates before us. Feature Writer Preyanka Makadia The researchers hope that their work will offer clues about the behavior of those with autism and other social disorders. Corresponding author Pier Ferrari is a biologist at the University of Parma, Italy Interviewee Pier Ferrari And we know that, for example, in the case of some social disorderslike in autismwe have impairment in the mirroring mechanisms, not just in terms of brain dysfunction in the mirror areas, but also deficits in imitative behaviors. So we know that there are neural mechanisms like this not just in the monkey brain but also in human brain you know, investigated through neuroimaging techniques. And we also know that these, you know, are recruited, these mirror area are recruited when humans imitate someone else. Feature Writer Preyanka Makadia The next step for other primate researchers may be to imitate their primates, says Laurie Santos. Santos is a cognitive psychologist at Yale University.

Interviewee Laurie Santos One of the reasons I think these findings are a breakthrough is that they just really provide an existence proof that actually we can study unconscious kind of processing in primates, and we can start to look at the evolutionary origins of these processes. And I think thats actually going to be very important for the field of comparative cognition at large. Feature Writer Preyanka Makadia And Paukner and her teams future research is to find out if capuchin monkeys subconsciously imitate each other. For the Science Magazine Podcast, I'm Preyanka Makadia. Host Robert Frederick You can read the paper by Paukner and colleagues on people mimicking monkeys, as well as a related Perspective, in this week's Science. Music Host Robert Frederick The Presidents Council of Advisors on Science and Technology, or PCAST, met in Washington last week for the first time under the Obama Administration. Here with more about the meeting is Science Policy Forum editor, Brad Wible. Policy Forum Editor Brad Wible PCAST is co-chaired by White House science adviser John Holdren, former National Institutes of Health director Harold Varmus, and MIT professor Eric Lander. PCAST members and invited expert guests discussed electronic medical records, environmental issues, and comparative effectiveness research, which evaluates medical interventions in areas, for example, where good studies have conflicting results or where evidence is not exactly relevant to patients. Issues surrounding comparative effectiveness research and health information technology have come up in the larger healthcare reform debate currently swirling around Capitol Hill. Questions abound on how information from comparative effectiveness studies will translate into practice. With electronic medical records, the challenges include incentivizing medical professionals to adopt the technology and ensuring that such technology is secure and user-friendly. Energy was also a topic of discussion. U.S. Energy Secretary Steven Chu talked about the need for energy research to be more innovative. He said that the challenges related to climate change and the idealism these challenges inspire have the potential to attract the next generation of scientists.

Council members also discussed topics that will be covered by several subcommittees, such as science education standards, advanced manufacturing for emerging technologies, private-sector R&D investments, orbital space debris, carbon offsets, and interdisciplinary agriculture research. The meeting was recorded, and if you are interested in viewing the webcast, go to www.ostp.gov/cs/pcast. Host Robert Frederick That was Policy Forum editor Brad Wible with a policy update from Science and the AAAS Center for Science, Technology, and Congress. Music Host Robert Frederick The ability to control fire allowed early humans to obtain light and heat, cook food, and make better tools. And scientists think that passing on that technological knowledge about fire, especially in tool-making, required the ability to use symbolic behavior, pictures, or even language. Now, in a paper in this weeks Science, archaeologists report evidence that early modern humans were using fire to make tools more than 100,000 years earlier than previously thought. Science's Brittany Johnson has more. Feature Writer Brittany Johnson Tens of thousands of years ago, early modern humans were using heat-treated tools in what is today South Africa. University of Cape Town archaeologist Kyle Brown and his colleagues set out to reproduce the stone tools they had gathered at the sites of Howieson Poort and Still Bay. At first, Brown says, they had no luck with chipping away at the stone in its natural form. [chipping sounds] Interviewee Kyle Brown Really out of desperation, I decided to try heat-treating, which is something I knew they did in more recent times, and pulled it out of the fire and, lo and behold, we saw a beautiful change in color and a change in texture, and they became much more easily flaked. Feature Writer Brittany Johnson The change in color was accompanied by a shinier appearance an important clue in solving the mystery. Interviewee Kyle Brown You will only get a change in the gloss or luster of the material once its heated and then flaked, which is what we used to decide whether its deliberately heat-treated and flaked after heat treatment.

Feature Writer Brittany Johnson In a process as elaborate as heat treatment, much of the effort is spent on preparation. Early humans needed to know what sources to tap into and whether or not it was worth their time and effort. Once firewood and suitable raw materials are obtained, however, the process of making the tools is fast and simple. Interviewee Kyle Brown It may not always make sense to do heat treatment. If the raw materials you have available to you work for what it is youre doing, then you may not choose to invest in heat treatment. Its a complex process. It requires you to be really careful when you build your fires. And these are hotter fires than youd be building for a normal cooking fire. So its a technique that they would have been teaching to the next generation of tool makers. Feature Writer Brittany Johnson The team believes the tools are about 70,000 years old. Archaeologists previously had discovered similar tools in Europe dating back to the Upper Paleolithic era, a period starting around 40,000 years ago, but Brown and his team found even older stone tools in Pinnacle Point, South Africa. Interviewee Kyle Brown The heat treatment study is documenting something that was originally thought to be a technique that was maybe 25,000 years old, and we pushed it much further back. And we believe that the technique was known as far back as 164,000 years ago. Feature Writer Brittany Johnson Of course, the controlled use of fire is not the only way to heat such objects. However, in the case of these early tools, Indiana University anthropologist Nick Toth says heat treatment is the most sensible explanation. Interviewee Nick Toth Is there any other explanation for how these early stone tools may have become heat-treated besides just intentional, I dont think so. They have a very reasoned approach. Theres little, if any, evidence that there was a lot of fires over the sites, so that if youre thinking of like brush fires, natural fires, or lightning strikes or things like that, I think its highly unlikely. Feature Writer Brittany Johnson Brown and his team conducted multiple tests of their hypothesis and examined how heat influences the width and thickness of the edges of stone tools. Toth, who is not an author of the paper, says that the team was very thorough. Interviewee Nick Toth They also used archaeomagnetism, thermoluminesence, and gloss values as part of their way of approaching this. And then, most importantly, they did a lot of experiments as well looking at unheated silcrete and then silcrete that they experimentally heated both in

a fire and in a controlled oven situation. So they have a very good empirical basis for then examining the archaeological material and comparing and contrasting it to their experiments. Feature Writer Brittany Johnson Researchers say the ability to shape raw materials may have helped early modern humans during their migration from Africa into Eurasia. The higher quality tools, they reason, could have been especially valuable in surviving the elements and trading with others. For the Science Magazine Podcast, Im Brittany Johnson. Host Robert Frederick You can read the paper by Brown and colleagues on heat treatment by early modern humans, as well as a related Perspective, in this week's Science. Music Host Robert Frederick What does it take for you to turn off a light when you leave a room, buy a more-expensive energy-efficient appliance instead of a less-expensive less-efficient one, or bundle up at home on cold days to save energy on heat? Whether you can change your behavior or not, Science's contributing correspondent Dan Charles reports that researchers say it will also will take regulation and taxation in order to make the kind of progress needed to reduce greenhouse gas emissions by conserving energy. Charles' report is part of a special News Focus this week that is all about energy efficiency. I spoke with him from Kiev, Ukraine. Interviewee Dan Charles Energy efficiency is back on the front burner. I guess it was famous back in the 1970s Jimmy Carter gave a couple of speeches along those lines. In recent years, it hasnt been talked about so much, but with the cast of characters now in the White House and the Department of Energy theres really a lot of attention being focused on how to save energy energy conservation, energy efficiency. And, you know, everybody pretty much agrees that there is a very big potential to make do with less energy, and its probably the most important, you know, part of a strategy for cutting greenhouse gas emissions. The question is, How can you do that? I mean is it going to be easy and is it going to be cheap? And so, thats, you know, really what a lot of people are trying to figure out. Interviewer Robert Frederick Is there an example from the past of one energy efficiency strategy that everyone thinks was successful? Interviewee Dan Charles Well, the example that a lot of people look at is the experience of California. You know, the most important things were probably, they put in place some regulatory measures energy efficiency standards on appliances and on buildings that really had quite a large

effect on the stuff thats on the market. The most dramatic example is probably refrigerators theres some great graphs that show dramatic improvements in the energy efficiency of refrigerators in a relatively short period of time. So, you know, theres this famous graph that people sometimes point to that shows per capita electricity consumption in California and in the U.S. And, you know, starting about 30 years ago the line for California basically leveled off, and then per capita electricity consumption in California has basically been flat for the 30 years. In the U.S., its continued to rise its gone up, you know, 35, 40%. So people look at that and say, See? The policys had a terrific, terrific impact. It turns out the story is not quite so simple. There were lots of other factors at play in California, including the climate and including sort of effects of population growth itself. But thats a thing that a lot of people, including the Secretary of Energy, Steve Chu, thats an example that a lot of people point to and say, This is what the U.S. government now should really pursue this same kind of strategy. Interviewer Robert Frederick Is there any scientific consensus about the best way to improve energy efficiency further promoting new technology, raising taxes, changing policy, getting information to consumers or is this perhaps a situation where it depends on the city or country in question? Interviewee Dan Charles You said is there scientific consensus? I, you know, my take on it, and Im a journalist not a scientist, but I dont really think its a scientific debate. Interviewer Robert Frederick So, there arent scientists out there studying these various strategies and looking at past implementation of policies and perhaps proposing new ones, getting groups of people together, hypothesis testing, things like that? Interviewee Dan Charles Well, okay. So, there is a debate among economists. You know, I dont know youd consider them scientists or not. Interviewer Robert Frederick Sure. Interviewee Dan Charles But, okay. So, there is a debate among economists, for instance, about how much you can just expect energy efficiency to be adopted purely because it pays for itself. In other words, you know, there are people who say there are innovations, theres new technology that really does if you look at sort of the payoff period, and, you know, the cost of capital and so forth you would say, Businesses and consumers, they should buy all this stuff right away, because its a better return on investment than it is, you know, putting it in a bank account or investing in stocks or doing any number of other things with their money. So, they would say, you know, Some of this stuff really should just, you know, take off by itself. Others say, No, it doesnt work that way theres all kinds of hidden

costs to adopting new energy efficient technology that, you know, some of these predictions dont take into account. Theres risk involved, theres time involved, theres all kinds of complicated, you know, other sort of obstacles that, you know, prevent people from doing that. So, theres a debate among economists. And, theres, you know, sort of a lively discussionI dont know if its so much a debatetheres a lively discussion about what will persuade people to do things its more sort of behavioral science. How do people think about energy, and what makes them, you know, choose to do one thing or another? What makes a person take the time to turn a light switch off when they leave the room? You know, thats a sort of a subject of lively debate and, you know, some disagreement. You know, but all of that is kind of at play. And if you ask a lot of these people theyll say, you know, The answer to what we should do is all of the above. You know, the taskif youre really trying to, you know, bring down greenhouse gas emissionsthe task is so big that, you know, no one strategy is going to work, you just have to try absolutely everything. So, theres a lot of enthusiasm, you know, about the behavioral side of these things. But on the other hand, there are still a lot of experts in energy efficiency and people who've sort of analyzed this problem who kind of say, You know, behavior really is sort of a minor piece of this. You can change peoples behavior and then, you know, youve made an improvement, youve had sort of a bump, but you do that once it doesnt continuously create a kind of a momentum of improvement. And so, they say, you know, the real kind of bang for your buck is still in technological innovation. Interviewer Robert Frederick Is there any new strategy out there that combines both of these ways of thinking about improving energy efficiency changing behavior and technological innovation say, a technological innovation that also helps change human behavior? Interviewee Dan Charles Right. Yeah, so there is a lot of interest in sort of the technical possibilities that come from making energy consumption visible, and how that affects the way people, you know, behave around their energy choices and their energy consumption. So, for example, you know, there are these things called smart meters that are going into millions of homes already and, you know, tens of millions in a few years. And all that is really is its a device that doesnt just measure your electrical consumption, but it also includes the ability to communicate that information to you. And this might be communicated directly back to a central office, and then you access it through a website, or it might be communicated, you know, sort of maybe through a radio signal or something directly to a display panel in your house. And then you could see what happens when you turn on a light switch; you can see what happens, you know, when during the night you see power still, you know, being consumed, and youre wondering what is that and then you think of all those little glowing and warm devices in your house the cable box, the power transformer on your computers or your printer or, you know, any number of other things. Similarly, the Prius is a good example of a display mechanism on the dashboard Interviewer Robert Frederick This is the car by Toyota.

Interviewee Dan Charles Yeah the Toyota hybrid people who drive these things are familiar with it. Its got this dashboard display that actually gives you a readout of your mileage as you drive, and you realize very quickly that your style of driving and what you do how hard you press on the throttle makes a difference. And so, a lot of people say they drive differently because of that. And theres an experiment actually going on at U.C. Davis right now where theyre expanding on that display and including different kinds of variables, like the readout will show drivers not just miles per gallon, but itll show things like how much this is costing you right now and others. So, theyre basically experimenting with different kinds of feedback and with test drivers trying to get a sense of how people react to that. So, this whole idea of making energy use visible and, you know, and actually developing maybe sort of a market in efficiency at the consumer level there are people who are quite excited about this and think it really will change things. Interviewer Robert Frederick Besides inertia or not wanting to change habits, codes, taxes, and the like did you identify in your reporting any people or groups or businesses that are purposely promoting less efficient practices? Interviewee Dan Charles You know, its a hard thing to say purposely promoting less efficient practices, cause I cant see inside the mind of anybody. But, so heres, heres a couple of things that I did sort of highlight in the story. You know, there are arrangements that exist in society that it almost seems like theyre sort of designed to promote waste. There are, and this isnt purposely designed, but its just kind of the way things are. And a classic example of this is basically rental housing where theres a distinction between the people who pay the bills and the people who actually make the decisions that control, you know, what the bills are. So, for instance, if the landlord is not paying the bills, that landlord is not going to install efficient windows because he doesnt see the benefit, or efficient lighting or any such thing. Interviewer Robert Frederick Because the renter is the one that pays the utility bills. Interviewee Dan Charles The renter pays the bills, but the renter doesnt usually get to decide, you know, whether to install new windows, right? So, you have this disconnect that its like a formula thats set up for the waste of energy. Because the landlord has an incentive to put absolutely the cheapest stuff in, into the house, and the cheapest stuff often is not very efficient. But, on the flip side, lets say the owner, the landlord, pays the utility bill, and the tenant does not pay the utility bills, whats that tenant going to do when it comes to running hot water or, you know, leaving the windows open with the heat running? Basically the tenant has no incentive to save energy either, because he or she is not paying the bill. Its called the principle agent problem where people get to make decisions and spend other peoples money. And they say this happens a lot. Now, people also look at the example

of the auto industry where cars have become remarkably more efficient in a kind of technical sense they get to move weight using less fuel but a lot of that innovation has gone into making cars bigger, heavier, and more powerful rather than promoting, you know, sort of higher miles per gallon figures. So, you know, you can ask yourself, "Whats driving that is it consumer preference?" And, you know, I think you can make a pretty convincing case that it is the car companies saw a market, you know, for these kind of vehicles. So, you know, a lot of people step back and say, How do you solve those kind of institutional problems? And they come back to kind of mandated standards, especially on buildings, because the industry is so fragmented, the only way to sort of create a community of builders and architects and designers and vendors that really know how to make an efficient building and are sort of up to speed on it is to sort of say, Okay, all you guys, you have to make a building that satisfies, you know, sort of this standard. And then, lo and behold, they sort of figure out how to do it. Interviewer Robert Frederick So, the best way forward then may be centralized legislation policies things that require everyone to comply? Interviewee Dan Charles Well, thats certainly one thing that probably has to be done. And, you know, the Obama administration is actually moving forward pretty aggressively on a whole family of appliance standards, but you cant just mandate everything. And so, you know, theres also a lot of interest in what you might call social marketing sort of spreading, you know, sort of increased awareness of things that people can do and also sort of building a social movement around the idea of using less energy. Interviewer Robert Frederick Internationally, any country that is leading by example? Interviewee Dan Charles Well, there are different countries that have done very well in different areas. So, theres a technology in the industrial arena, called combined heat and power cogeneration, where you basically, you know, have a power plant where the excess steam gets reused, and they're very efficient. And both Denmark and the Netherlands to very well at that. Obviously, there are a lot of countries where public transportation is much more widespread countries in Europe, for instance, and Japan. So, those are positive examples. The Scandinavian countries have these terrific heating systems, called district heating, where theres actually steam piped through pipes and into buildings. But, thats something that its very hard to imitate you kind of have to build that from the ground up. So, the U.S., in some ways, with things like building standards and efficient appliances is really not too bad, but if you step back and look at overall efficiency levels it does tend to correlate with energy prices. In other words, places where energy is expensive, they find a way to use it more efficiently. Interviewer Robert Frederick

So, will we be seeing, then, an energy tax to get these ideasthese energy efficiency standardsimproved? Interviewee Dan Charles That is a totally political question or a political issue and there are a lot of people who say its absolutely essential. But, it doesnt sound like, you know, the government is moving very aggressively in that direction. I mean, that is the point of, you know, the carbon trading system, is to impose a cost on emitting carbon. But that, it seems like depending on what gets through Congress, it might end up getting phased in rather slowly. Interviewer Robert Frederick Dan Charles, thank you very much. Interviewee Dan Charles Nice to be with you. Host Robert Frederick Science contributing correspondent Dan Charles on the persuasion, regulation, and taxation researchers say is needed to significantly improve energy efficiency. Music Host Robert Frederick Finally today, David Grimm, editor of Sciences online daily news site, ScienceNOW, is here with a wrap-up of some of the latest science news, including a story about whether clouds come from outer space. Okay, convince me. Interviewee David Grimm Well, Rob, this isnt about clouds actually coming from outer space its about clouds getting their start in outer space. Interviewer Robert Frederick How so? Interviewee David Grimm Well, first we need to talk a little bit about how clouds form in the first place. And actually, despite how ubiquitous clouds are, scientists really dont know that much about how clouds form. They suspect that it has something to do with aerosols in the air, so think about particles from dust or pollen as they drift up into the air they serve as nuclei for water droplets to form. So, they attract water droplets, and these droplets attract more droplets until youve got trillions of droplets, which form a cloud. And we can see an effect like this in big cities where you have a lot of exhaust from cars these particles in the exhaust can also nucleate cloud formation. Interviewer Robert Frederick

Bacteria, too, I understand. Interviewee David Grimm Exactly. But, that still leaves open a bunch of questions. First of all, obviously theres big areas of the Earth that dont have dust or that dont have exhaust from cars. Interviewer Robert Frederick So, there are places where clouds dont form? Interviewee David Grimm Well, thats the issue, Rob. I mean clouds form everywhere, so even over vast swaths of ocean where you dont have dust or obviously dont have car exhaust or pollen and youre still seeing clouds. So there must be another explanation, or at least an additional explanation, for how clouds form on Earth, and thats where outer space comes in. And, specifically were talking here about cosmic rays. And cosmic rays are these very mysterious high-speed protons and neutrons that travel at nearly the speed of light, and theyre from unknown origin, but they hit Earth, and the idea is is that these rays collide with water molecules in the atmosphere, and they strip away electrons from these molecules and convert them into electrically charged ions. And these electrically charged ions begin attracting water molecules, which attract more and more water molecules to form a cloud. So its these electrically charged ions that sort of serve kind of like a dust grain or a pollen grain would they nucleate cloud formation. Its a pretty wild theory, but it actually has some support. A few years agoactually in 2006a team showed in the lab that this was possible they bombarded water molecules with a particle beam, and they were able to show that these water molecules acted a lot like aerosols like, you know, the dust and pollen aerosols that could potentially attract water molecules and form clouds. Interviewer Robert Frederick And so, now theyve somehow expanded that experiment to try it out on Earth? Interviewee David Grimm Exactly. Well, you know, that was just in the lab, and so they really wanted to see, Well does this actually hold water? as it were, in the real world. Interviewer Robert Frederick Bad pun, Dave. Interviewee David Grimm And so, what the researchers did was they focused on something called a Forbush decrease. And, it sounds very complicated, but basically what it is, is a Forbush decrease happens when there is a massive storm on the Sun, which flings this super hot fog of particles, called a coronal mass ejection, past Earth, and what this fog of particles does is, it actually shields Earth from these cosmic rays. Interviewer Robert Frederick

So, while the Earth is shielded I guess there would be a decrease in clouds? Interviewee David Grimm That would be the idea. If this cosmic ray theory is correct, then if Earth is getting less cosmic rays, then it should also be getting less clouds. And what this team didthe same team that did the lab experiments a few years agowas, they looked at about 22 years of data from weather satellites that really have very detailed information about cloud formation and even how much water is in the clouds. And they compared that with 26 Forbush decreases. And, what they found is that for the 5 strongest Forbush decreases they saw a decrease in the water droplet content of Earths clouds by about 7%. Interviewer Robert Frederick Is that statistically significant? Interviewee David Grimm Well, its significant enough that the researchers say its sort of like seeing bare patches forming on a field. In other words, youre seeing, youre actually seeing this noticeable reduction in the water content of Earths clouds. So, its a correlation; its not direct proof, but its the strongest evidence yet that there could be a link between these cosmic rays and cloud formation on Earth. Interviewer Robert Frederick How long did it take before these patchesthese bare patchesfilled in, before cloud cover returned to normal? Interviewee David Grimm The researchers say it took a few weeks for the cloud cover to return to normal after these Forbush decreases. Interviewer Robert Frederick And what are other researchers saying about this apparent causal link or at least correlation between coronal mass ejections and this decreased cloud cover? Interviewee David Grimm Well, researchers are excited about it this theory has sort of been in the ether for a while, but people have had a really hard time proving it. And, experts say this really is the strongest evidence yet that there seems to be a connection. Now, again it doesnt prove it because its a correlation, but it definitely gives this very wild theory some credence. Interviewer Robert Frederick Okay, so what other stories have you brought with you this week? Interviewee David Grimm

Well, Rob, from clouds needing a little help from outer space to get forming, to horses needing a little help from their friends to have healthier offspring. This next story is all about how the social bonds that animals form may actually be evolutionarily important. Interviewer Robert Frederick Friendship as an adaptation? Interviewee David Grimm Exactly. And, the idea stretches actually back to some studies with humans that have shownespecially in studies with womenthat have shown that friendships tend to lead to healthier babies. Now, talking about correlations this is again a correlation, but theyve also seen this effect in other animals. For example, there were some studies done with baboons that showed that female baboons that form friends in baboon societies so, in other words they form these social bonds with non-relatives tended to have infants that survived longer. So, theres this evidence out there that friendship seems to be important and actually seems to have real world implications for how healthy your offspring might be. Interviewer Robert Frederick So theyve extended this now to horses. Interviewee David Grimm Exactly. They wanted to see how far-reaching this effect was. And, obviously, the species that you look at the farther away they are from humans, if they still have the same traits, it shows you that this is a very conserved behavior and therefore must be very important, especially from an evolutionary sense. Interviewer Robert Frederick So, what traits go into a horses friendship? Interviewee David Grimm Well, in this study the researchers looked at a group of about 50 adult maresso thats female horsesin New Zealand. And these mares were part of a larger population of wild horses, so these were feral horses they werent pet horses. And the way these researchers defined friendship is that occasionally the females would nuzzle each other, you know, other females that werent relatives; they would also groom each other; and, they would also just spend some time standing very close to each other, so sort of like the horse equivalent of just hanging out with your friends. And what the researchers found was that the mares that spent a lot more time hanging out with their friends had much healthier offspring. In fact, the mares that were the most sociable had offspring that survived twice as long, on average, as the mares that were least sociable. Interviewer Robert Frederick What do researchers think might be the reasons for this increased reproductive success? Interviewee David Grimm

Well, the mechanism is a little unclear. What they do know is that these mares tend to get harassed a lot by stallions that are apparently asserting their sexual dominance. So, one idea is that as these mares stick together they seem to be less harassed by the stallions, and maybe thats healthier for their offspring. And theres also some other theories about why friendship might be evolutionarily important. Some researchers have speculated that it helps animals band together better to avoid predators, and it also seems to reduce stress in pregnant mothers, and stress has been shown to adversely affect the growth rates and the survival of offspring. So, taken together, all of these things seem to indicate that when female horses make friends, theyre actually providing a big benefit to their offspring. Interviewer Robert Frederick Well, I see you have one more story with you this week. Whats that one about? Interviewee David Grimm Well, Rob, from horses to birds this last story is about how bird flu might cause Parkinsons disease. Interviewer Robert Frederick The neurodegenerative disorder. Interviewee David Grimm Right. Parkinsons is this disorder where people tend to sort of lose control of their motor functions they shake a lot or in some cases they actually cant move at all. So, its a very debilitating disorder. And, the essence of this study really goes back to a controversial idea in neuroscience, which is that viruses can cause neurological disorders. Now, when we typically think of viruses like the flu virus, we think of, you know, coughing and sneezing, but theres been this theory around that these viruses can have a much more insidious impact on our bodies that they can affect our nervous system and years later can cause these very debilitating neurological problems. Interviewer Robert Frederick So, do they have evidence from past flu epidemics that theyre looking at? Interviewee David Grimm Well, one very strong circumstantial piece of evidence comes from the 1918 flu, which is also known as Spanish flu, and this was a very devastating flu it killed tens of millions of people around the world. And what researchers noticed is that years after this flu struck, a lot the survivors seemed to have diminished mobility and other neurological symptoms that were reminiscent of Parkinsons. Interviewer Robert Frederick So, not Parkinsons just something that looked like Parkinsons. Interviewee David Grimm

Something that looked like Parkinsons. And researchers saw something very similar in this recent outbreak of bird flu this is the H5N1 virus. And when they looked at chickens and geese, and ducks in Laos that had been infected by the bird flu virus, they saw that the birds looked like actually had Parkinsons disease they exhibited a lot of symptoms that humans exhibit when they have this disease. So, there was again some strong circumstantial evidence that a virus could cause these dramatic neurological symptoms. Interviewer Robert Frederick So, there isnt evidence for this decreased mobility in people yet because not enough time has passed by? Interviewee David Grimm Exactly. You know, bird flu just arose again very recently, so it may take years before we seeif we see at allthese symptoms in people. But, they wanted to get a a much quicker idea of whether this link really does hold true, and so what they did was, they looked at mice, which also have a very short lifespan, and they sprayed a solution containing the H5N1 virus into the noses of over 200 mice. And what they noticed was that all of the mice developed tremors and movement difficulties again, very similar to what youd see in something like Parkinsons disease. And, they went further this time rather than just looking at the symptoms they did some labeling of these viruses to see where they went in the body and sort of just what sort of impact they were having. And they noticed that after 10 days of the virus being in the body, it started appearing in the brain. And after about three weeks mice had cleared the virus, but the symptoms of the virus having been in their body remained. Researchers noticed increased inflammation in the brain, where they had seen the virus previously. They also noticed abnormal clumps of protein in the brain, which is a symptom thats also seen in Parkinsons disease. And finally, they noticed a decrease in dopamine-releasing neurons. And, in people with Parkinsons disease, they lose about 70% of these neurons, and they saw in the mice that the mice lost about 17% percent, so its not nearly 70%, but it does show again this, what seems like a very strong link between this viral infection and the beginnings of these neurological symptoms. Interviewer Robert Frederick So, does this suggest then that people who get the flu will be more likely to get Parkinsons disease, or if they get it, then theyll have a more severe version of it because of this previous bout with the flu? Interviewee David Grimm Well, the findings do suggest that if viruses dont cause these symptoms they at least may predispose us to these neurological symptoms. But experts are saying, Lets not get too panicked right away dont just assume next time you get the seasonal flu that youre going to develop Parkinsons disease down the line. This most direct work so far has only been in mice, which are still far away from humans, so they say a lot more work has to be done, and we really have to figure out exactly whats going on here before we get too worried about the connection between viruses and neurological diseases.

Interviewer Robert Frederick The mice, then, just had decreased mobility, the 17% you talked about, not the full-blown 70%, like people who have Parkinsons disease. Interviewee David Grimm Right. The mice werent exactly replicating what we would see in a human version of Parkinsons disease, which is why one of the theories these researchers have is maybe these viruses dont actually cause the disease; maybe they just sort of prime us, they make our brains maybe weaker and more susceptible to this disease down the line. But again, its all still very preliminary at this point. Interviewer Robert Frederick Okay, well, thanks, Dave. Interviewee David Grimm Thanks, Rob. Interviewer Robert Frederick So, what other stories are you looking into for ScienceNOW or on the policy blog, ScienceInsider? Interviewee David Grimm Well, Rob, for ScienceNOW were looking into a story about the link between hurricanes and climate change. Theres been a controversial theory out there that climate change is causing an increase in hurricane strength and frequency, and researchers are looking into that. And also, a story about could Neanderthals taste bitter foods? And it turns out it looks like they could. So, check out both of those stories on ScienceNOW. And, on the policy blog, ScienceInsider, were looking into a story about the NIH childrens study. And, this was originally slated as a three billion dollar study that would follow 100,000 children from birth to age 21 a very, very big study on age. And it turns out the study may actually be costing six billion dollars, so twice as much as the researchers had proposed. And, there seems to be some stuff going on with perhaps hiding costs from Congress, and there may be some staff shakeups with the study, so a very interesting story thats still in progress, and were following that as that develops. And also, were looking into efforts to sequence the human genome much faster and much cheaper than has ever been done before. So be sure to check out all of these stories on the site. Interviewer Robert Frederick David Grimm is the editor of ScienceNOW, the online daily news site of Science. You can check out the latest science news, plus find a link to the science policy blog, ScienceInsider, at sciencenow.sciencemag.org. Music Host Robert Frederick

And that wraps up the August 14th, 2009, Science Magazine Podcast. If you have any comments or suggestions for the show, please write us at sciencepodcast@aaas.org. This show is a production of Science Magazine with the support of AAAS, the Science Society. Jeffrey Cook composed the music, and I'm Robert Frederick. On behalf of Science Magazine and its publisher, the American Association for the Advancement of Science, thanks for joining us. Music ends