This article is from the In-Depth Report The Chernobyl Nuclear Accident 25 Years Later
Science Talk

Bering Sea, radiation, historic tortoise.

In this episode, science writer Karen de Seve shares her adventures in the Bering Sea; journalist Dr. John Miller talks about a radiation health conference; and taxonomist and paleontologist Scott Thomson discusses the late Harriet the tortoise. Plus we'll test your knowledge about some recent science in the news. Organizations and websites mentioned on this podcast include the Liberty Science Center,; Karen de Seve's blog,; the American Statistical Association,; Wikipedia,; and the Scientific American Digital Archive,

Science Talk June 28, 2006 -- Bering Sea, Radiation, Historic Tortoise

Welcome to Science Talk, the podcast of Scientific American for the seven days starting June 28th. I am Steve Mirsky. This week on the podcast, we span the globe from A to A—Alaska to Australia. Science writer Karen de Seve talks about her trip to the Bering Sea to observe research there, journalist John Miller discusses a recent conference on the health effects of radiation, and we will hear from Chelonian expert Scott Thomson Canberra, Australia. If you don't know what a Chelonian is, good, stick around. First up, Karen de Seve. She is a science writer at the Liberty Science Center located right behind the Statue of Liberty. She had just gotten back from the Bering Sea when we spoke at the offices of Scientific American.

Steve: Hey Karen, thanks for joining us.

Karen: Thanks Steve. Glad to be here.

Steve: What were you doing in the Bering Sea?

Karen: Well, I got a chance to go, be on a U.S. Coast Guard icebreaker called the Healy, which is the largest scientific ship in the fleet, and there is a series of research projects going on there that I was reporting on and filming for an exhibition that's coming up at Liberty Science Center in Jersey City, New Jersey.

Steve: Was it cold, for one thing?

Karen: It was pretty cold. They are right in the middle of what they call the springtime blue and so this is normally the time that the ice would start melting up there and they had a pretty good ice year, and what they have found is in the past few years the ice hasn''t been quite as good. So, this year was a little bit colder. Yeah, we find ourselves wrapped up in hats and scarves and things out on deck while a lot of science was going on.

Steve: What dates were you actually out there?

Karen: I left on May 23rd. I got on the boat. They helicoptered me from Nome, Alaska to the Healy on May 24th and then, I got back in the helicopter and left the ship and went to Gamble on St. Lawrence Island to the tiny island 35 miles from Russia right in the middle of the Bering Sea. So, I was on the ship for six days. The entire crews and all the scientists were on board for a month.

Steve: Okay, Gamble is the name of a place. You didn't get off the ship to gamble.

Karen: No, I did not. It's a subsistence hunting village. The people there speak Siberian Yupik, which is a native language that's spoken in Russia as well as on this island; and there is by 800 people there, no pavement, no gambling, lot of hunting.

Steve: What were the scientists doing on the ship?

Karen: There were a lot of scientists on the ship and overall they were looking at the effects of climate change on the ecology of the Bering Sea. The two lead scientists were Lee Cooper and Jackie Grebmeier. They are based at the University of Tennessee and they were the chief scientists. There were about 30 other scientists on board, each one studying a different piece of the puzzle of how climate change is affecting the animals really from the bottom up; looking at the animals that live on the bottom of the ocean and finding out where they get their nutrients, and those are the animals that feed the walruses and whales and diving birds and things that depend on sea ice to survive. The Bering Sea is a continental shelf, and it's one of the most productive regions in the world and a lot of people rely on the animals that live there; the local natives rely on the animals, the walruses, the whales and those animals rely on the sea ice. So, what the researchers were trying to find out is if the sea ice is receding north and melting sooner [and] how does [it] affect that [the] animals that rely on this region. So, they were looking at the timing: How long after the sea ice does the algal bloom start the algae that really forms the basis of the food web? So, this algae sinks to the bottom, it feeds the animals living in the mud on the bottom of the seafloor and then the diving birds and walruses eat those things that are in the mud. So, it's all interconnected. The scientists are really interested in: Are these animals going to have to move farther north with ice? Are there going to be fewer nutrients? Are other fish that usually live farther south going to start moving north in competing for food? It's really, you know, how is climate change is going to affect the whole system?

Steve: And, how do they do this kind of research? Were they throwing things over the side along and dragging them back up?

Karen: Essentially that's what they are doing, but it's a lot more organized than that. They are deploying lowering down by these huge winters[winches] giant nets of different sizes, raise water tubes, different sensors to measure temperature, salinity, connectivity of water, as well as chlorophyll in the water, which will tell them where algae are in the different levels of the water column. So, you know, there is a whole team. They work 12-hour shifts and they stop at stations. I think they did a 100 stations and at each station they have a series of different equipment that they deploy over the side.

Steve: And, that's one of the reasons we are talking now instead of on the ship, because you did have telephone access on the ship, but you said this [that] the winches were drowning out everything else.

Karen: Yeah, I was doing a lot of filming and at one point I just unplugged the audio on my camera, the winches were very, very loud but you kind of just got used to it after awhile. The phone, they had a satellite phone, which was a little bit dodgy and we did have a little bit of Internet access, but otherwise this ship is completely wired. It's designed for scientific research and the researchers there are really grateful to be able to get out there and do what they need to do with all of the equipment they need available to them.

Steve: How long will it be until the researchers are publishing their findings based on what they dredged up?

Karen: Some of the people said it would be at least three months until they could write something and then, of course, it goes through review process for several months. So, you know, we would probably see something in six to eight months I would think.

Steve: And, how long is it going to be until your exhibition goes up at the Liberty Science Center?

Karen: Our exhibition will probably be going up next summer; summer of 2007 would be our reopening of the entire science center. This will be part of a breakthrough series, which will cover current science news and this in particular; one will be in conjunction with the International Polar Year, which starts in 2007.

Steve: Thanks a lot Karen.

Karen: Thank you Steve.

Steve: You don't have to wait till 2007 though. For a lot more from Karen de Seve on her Bering Sea adventure, check out her blog of the trip featuring audio and video taken aboard the ship; it's at We will be right back.

For breaking news about science and technology, visit today.

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: Harriet the tortoise died in Australia last week. She was about 176 years old and was very possibly collected personally by Charles Darwin.

Story number 2: A snake was discovered in Borneo that can change colors like a chameleon.

Story number 3: A species of meteorologist monkey takes recent weather into account when figuring out which fig trees are most likely to provide tasty treats.

Story number 4: A study of the behaviors of people in the world's biggest cities found that New Yorkers are indeed the rudest people on Earth.

We will be back with the answer, but first John Miller is a freelance science journalist with a specialty in the health effects of radiation exposure. For more info on that subject, I called him at his home in Cleveland.

Steve: Hi John, how are you?

John: I am just fine Steve and you?

Steve: I am okay. Tell me about this conference you were at.

John: I was at a conference sponsored last week by the American Statistical Association that was called "Radiation Research: State of the Science Twenty Years after Chernobyl."

Steve: You have a very interesting background for a science journalist. Let me take a minute with that. You are a PhD psychologist, which means you have a lot of experience with statistics for one thing.

John: Yeah, in psychology you can have a 100 variables roaming around. You got to be pretty damn good inferential statistician.

Steve: And, tell everybody about your radiation experience.

John: Well, I was an officer on a fast-attack nuclear submarine couple of lifetimes ago, where I not only learned a lot of nuclear engineering, but I also had to learn all of the radiation health knowledge that we had at that time. I never really believed it totally and scratched my head about it and said one of these days I want to figure this out for real and go talk to the real radiation researchers, and that's what I did.

Steve: So, you went to this conference with your unique background and you were the only journalist at the conference. Is that right?

John: That's right and that's the way it is most of the time in the last, say, three or four years. I have gone to five or six of these conferences. I have met all these researchers. They are all friendly and open to me and only once was another journalist there.

Steve: That's fascinating. So, a lot of this information is being generated and presumably is being analyzed by the scientific community, but we are not really hearing about it.

John: Yeah and that's a real shame because in the last, say, eight to 10 years this field has just exploded. These researchers came late to the recombinant DNA techniques and they also had to wait for some technical advances like being able to send one gamma into one cell and now that they radiate it. You just couldn't do that before and that has lead to this explosion [of] what we thought we knew 10 years ago and 50 years on some important topics is really quite different than we thought; and it's anybody's guess now whether that makes radiation a good bit more damaging than we thought or perhaps makes it a good bit less damaging.

Steve: Let's talk about—give me some specifics from the conference about radiation and [a] particular disease or [a] particular cancer.

John: Sure. Let's try thyroid cancers. We know now that there have been nearly 5,000 thyroid cancers developed in people who were either children or were teenagers back in 1986 when the Chernobyl accident happened, and I am talking about children and teenagers who live either in Ukraine, Belarus or Western Russia. You don't usually die of this disease—it's only about 15 people of the 4,800 have died—and we don't know how many of these cases to expect in the future. Researchers say to expect some, but they can't tell you because before now we never had a large group of people who got their thyroids irradiated internally. These people got them from Iodine 131. It falls on the ground after Chernobyl; a cow eats grass that it fell on; the cow produces milk; children drink the milk; and the Iodine 131 goes straight to their thyroids. We didn't expect this because in the aftermath of the A-bombs on Hiroshima and Nagasaki we didn't see a large number [of] these. It turns out that there's a very big difference between getting irradiated externally, say, from the gamma rays of an A-bomb than from being irradiated internally from the gamma rays and beta particles from Iodine 131.

Steve: And, have the guidelines for radiation exposure been based pretty much on the limited data available from evaluations of the populations that were exposed to the A-bombs?

John: Yeah. Almost everything is based on that. It turns out that we are like the drunk who looks for his keys under the lamppost; it's really the only huge data set that we have got and so, one of the problems in translating from a situation like that where it was just one radiation dose—the fireball went so high in the air and the wind carried it off the island of Japan and dropped it in the ocean that there was very little residual radiation left—compare that to Chernobyl where the dose wasn't given once, the dose was given in a protracted way, people have been getting it for years. But it is a big, big problem trying to say in any of these situations where you get radiation over a longer period of time, exactly how it does it equate with the damage we saw after the A-bombs were dropped.

Steve: Do you have any other conferences on the subject or plan that you are going to be going to?

John: Just next month I am going to go to Department of Energy's so-called low-dose radiation conference. About 10 years ago a lot of money was voted by Congress to do a 10-year study of the effects of low-dose radiations [that was] incredibly productive.

Steve: Very interesting. Well, you know, let's make sure to talk again in a few months when there is some new stuff to talk about and I thank you very much, John.

John: My pleasure.

Steve: For more info on the conference Miller attended, go to the Web site of the American Statistical Association—that's and then hit the link for meetings and events.

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

Tortoise dies that Darwin may have personally collected 170 years ago.

Snake found that can change colors.

Monkeys track the weather for deciding which fig trees to forage, and

New York City, where I am right now, is the rudest big city on Earth.

"Hey, I'm talking here. Your time's up."

Story number 1 is true. The recently departed Harriet the tortoise is thought to have been collected by Darwin himself during his visit to the Galapagos in 1835 or 1836. More on that in a moment.

Story number 2 is true. A snake was discovered deep in the jungle of Borneo that has the ability to change color. World Wildlife Fund researchers discovered the chromatic capacity when they put the dark snake in a dark bucket and it turned white. Since it's obviously not disguising itself like a chameleon with its color changes, perhaps the poisonous snakes change to white was a red flag.

Story number 3 is true. Gray-cheeked mangabey monkeys in Uganda rely on recent trends in temperature and solar radiation when figuring out which fig trees to forage for figs and also insect larvae. Weather is a big factor in determining which trees are more likely to offer up the good figs and grubs. You can read more in Tracy Staedter's article on the foraging meteorological monkeys at

All of which means that the story about New Yorkers being the rudest people on the planet is TOTALL.......Y BOGUS, because Reader's Digest did a study that tested people in 35 of the world's biggest cities to see if they held open doors, said thank you, and helped pick up dropped papers, and New York City was in fact found to be the most polite big city in the world. "You got a problem with that?"

You know we just talked about the death of Harriet the tortoise and some press reports cast doubt on her personal connection with Darwin. Scott Thomson is a taxonomist and paleontologist at the University of Canberra in Australia. He's also a big fan of chelonians, i.e., he is an expert on turtles and tortoises and he was a close associate of Harriet the tortoise over the last 20 years of her long, long life. Thomson thinks that Harriet, who went from the Galapagos to England to Australia well before Abe Lincoln was elected president, may indeed have been collected by Darwin. To find out more I called Thomson in Canberra.

Steve: Hi Dr. Thomson. How are you?

Thomson: Not too bad, thanks.

Steve: Great. Let me ask you about Harriet. With her passing there, there have been some reports that talk about her possible direct connection to Charles Darwin and a lot of the newspaper coverage has also noted that it's probable that those reports are apocryphal. One of the key issues raised is that she is from one island that he never visited. I think you have some interesting light to shed on that issue.

Thomson: I have no problem if the story gets shown to be wrong, but I would rather [it] would be done with facts, rather than with opinion.

Steve: You have done DNA analysis on Harriet, the individual tortoise.

Thomson: We managed to identify what subspecies she was. It wasn't easy. She actually couldn't in the initial run be identified to any known population of Galapagos tortoise, and the reason it ended up being is because she has actually got a much higher genetic diversity and is far removed from any of the living animals around that were also used in the study that shows her age that does not obviously prove that she was with Darwin.

Steve: So, that tells you that she was very, very old.

Thomson: Yes, at least 1860. It showed us that she couldn't be any younger than that. She could have been born anytime before that.

Steve: Got you.

Thomson: Anyway, what we also show was that she was from Santa Cruz Island and that of course means she is from an island that Darwin didn't visit and that's correct, but the interesting thing is that the three islands that Darwin did collect on—one of them the tortoise's subspecies from that island had actually gone extinct before Darwin got there, yet he collected tortoises on that island and the reason for that was that there was a prison colony on the island. They had actually exterminated the population. What happened was that they were then going out to all the other islands collecting tortoises and taking them back to Santa Marino Island to use for food and Darwin collected those.

Steve: So, it is very possible that Harriet was from an island that Darwin didn't visit, but wound up on an island that he did visit and that's where he collected it.

Thomson: Yes, basically.

Steve: How did you get so interested in Harriet?

Thomson: Well, to start, it was my job to do it. [I] am always developing management plans for tortoises in Australia and New Zealand and Harriet was just a part of that plan, and as her history unfolded, we saw that it was quite interesting and then further into it was kind quite spectacular. So, Steve and Terry Owen and I published it in 1995 what we had found.

Steve: This is Steve Irwin, known in America as the Crocodile Hunter.

Thomson: Yeah, that's right. And we had the DNA analysis done by Ed Lewis at Texas A&M University that was a study for 900 animals. Harriet was just one of the animals in the study—and yes, the results as I have said before showed that she was extremely different from any of the other animals in the study.

Steve: Is it amazing to you that in your lifetime you dealt with an individual that Darwin likely dealt with in his lifetime?

Thomson: I find her wakeful times to be extraordinary and I think it's very sad that she died, and she is not the only tortoise that has been in my boat, there have been other quite old tortoises around, but I guess this one I actually got to deal with personally and directly and I knew Harriet for 20 years and, I mean, she really kind of mean[s] a lot to me, I mean, I worked on thousands of turtles as a biologist but she is probably the only one I have become so personally attached to it.

Steve: Thank you very much Dr. Thomson.

Thomson: Not a problem.

Steve: Scott Thomson is the author of the recently updated Wikipedia entry on Harriet. Just go to Wikipedia, search the word "Harriet" and it comes right up. We will be right back.

Rennie: Hi, I am John Rennie, editor-in-chief of Scientific American. Our magazine is now available in a digital edition. Not only does your Scientific American Digital subscription include the full contents of every new printed issue, it also entitles you to access our digital archives from 1993 to the present. For more information, visit

Steve: 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, I am Steve Mirsky.Thanks for clicking on us.

Organizations and Web sites mentioned on this podcast include the Liberty Science Center, Karen de Seve's blog, the American Statistical Association; Wikipedia, and the Scientific American Digital Archive,

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