Dennis McGillicuddy, Associate Scientist (AOP&E) deploys a drifter in the Bay of Fundy. (Photo: Mike Carlowicz © Woods Hole Oceanographic Institution)

MCGILLICUDDY: (LAUGHS) Nothing at all. Dinoflgellate is a single-celled algae, that uses light energy from the sun and nutrients from the deep sea to carry on the process of photosynthesis.

CURWOOD: But in this case, this is something that we don't particularly like. Why?

MCGILLICUDDY: As part of the cellular metabolism, this particular dinoflagellate, Alexandrium fundyense, creates a very potent toxin, called saxitoxin, which when accumulated in high enough concentrations, is a serious threat to human health.

CURWOOD: How is it that this particular algal bloom grew so fast?

MCGILLICUDDY: Well, this is exactly what we are studying at the moment, and it's a little too early to tell for sure, as this bloom is still unfolding before our eyes. But we have three main hypotheses. But to understand these hypotheses, I first need to say a few words about the life cycle of Alexandrium. It's a very complex life cycle for a single-celled algae.

CURWOOD: Okay.

MCGILLICUDDY: It actually has a benthic cyst stage. That is, it can live in the sediments for period of months, to in excess of years as a resting cyst on the bottom.

CURWOOD: The benthic meaning the bottom?

MCGILLICUDDY: That's right. And due to an endogenous clock that's present inside the cell, it will begin to germinate in about April or early May of every year. Once the cysts germinate, they swim upward into the light to begin their phase of vegetative growth, when the actual bloom dynamics occur.

CURWOOD: So you say that there are three basic notions as to why we have a rapid growth this year. Behind door number one?

MCGILLICUDDY: (LAUGHS) Behind door number one is that it appears that the source population, that is the source of benthic cysts, is larger now than it was the last time the cysts were surveyed. There was a very intensive survey of the benthic cyst distribution in the fall of 2004, just this past fall. And the overall finding was that the amount of cysts in the sediments, particularly north of Cape Anne, was much higher than it was the last time those cysts were surveyed back in 1997.

CURWOOD: Hmm, okay. And then behind door number two?

MCGILLICUDDY: Behind door number two is the fact that transport conditions were favorable in this area to deliver those source populations into Massachusetts and Cape Cod bays. You may remember that there were two very strong Northeaster-type storms here in the coastal ocean in May. Those strong winds out of the North and Northeast tend to channel the currents in the coastal ocean to deliver those source populations into Massachusetts and Cape Cod bays.

CURWOOD: And the third prospect here, the third hypothesis?

An Alexandrium cell. (Photo: Kristin Gribble © Woods Hole Oceanographic Institution)

MCGILLICUDDY: The third hypothesis is that the growth conditions are favorable for the blooming of Alexandrium. Those same Northeaster storms that were responsible for favorable transport may also be responsible for setting up favorable bloom conditions. That is to say, those very strong winds cause a lot of waves and turbulence on the surface ocean. That tends to entrain nutrients from the deep sea into the surface layers, which would then sustain blooms of Alexandrium, as well as other plankton. What remains behind door number three in that there is one other possibility that may have led to favorable growth conditions, and that is that we have much higher than average rain runoff into the coastal ocean. That is, freshwater that is emanating from rivers all up and down the coast. That is much higher than average this year, and that would also tend to deliver nutrients to the coastal ocean and create favorable growth conditions.

CURWOOD: Now how come the red tide effects mussels and clams, but not lobsters amd shrimp?

MCGILLICUDDY: The reason that shellfish are so effected is because they're like little underwater vacuum cleaners. The typical market-sized mussel is filtering at a rate of ten liters of seawater per hour, 24 hours a day, seven days a week. And so there's an enormous capability for concentration of the toxins that they’re accumulating as they filter the plankton out of the water. Other organisms that don't filter-feed like that simply don't accumulate nearly the concentrations of toxins that the mussels and clams do.

CURWOOD: Now I understand that even after this particular red tide goes away from Massachusetts Bay and the Gulf of Maine here along the northeast, that its impacts could be felt for years to come. Why is that?

MCGILLICUDDY: The reason for that goes back to the life history strategy of this particular organism. Once the cells face some sort of environmental stress, say like nutrient limitation or temperatures that are too high, or salinities that aren't suitable for their growth, the cells will then go through a phase of sexual reproduction, then form a new cyst and sink down to the bottom. Now those benthic cysts are a way for the organism to persist for years and years to come. Now if as a result of this extraordinarily large and intense red tide, a whole new set of benthic cysts are formed and deposited in new areas, that could lead to serious problems in the coming years.

CURWOOD: Dennis McGillicuddy is with the Woods Hole Oceanographic Institution, and is also Deputy Director of the Woods Hole Center for Oceans and Human Health. Dennis, thanks for taking this time with us today.

MCGILLICUDDY: It's my pleasure.

Back to top

[“PICTURE START” FONTANELLE: FONTANELLE (KRANKY) NO DATE]

Emerging Science Note/Multi-talented Bacteria

CURWOOD: Just ahead, the hunt for a tiger that's not really a tiger, and may not even exist anymore. First this note on emerging science from Jennifer Chu.

[EMERGING SCIENCE THEME MUSIC]

CHU: Think bacteria and you probably think malicious agents of disease. But researchers at the Medical University of South Carolina say think again. They’ve found a bacterium capable of cleaning up pollution and generating electricity at the same time. The bacterium is commonly found in freshwater ponds, and scientists say it’s not the first time bacteria has been identified as a power source.

But what makes this microorganism special is its ability to deactivate some of the most toxic groundwater pollutants, including industrial solvents used in plastic production, by de-chlorinating them. These are also the first known electricity-producers that form spores, dormant bacteria which need no water or oxygen and are resistant to heat and radiation. That makes them useful in the noxious environments where pollutants are often found. And that’s not all. These bacteria can also cause some heavy metals found in water to precipitate back into solid form, making them easier to remove.

The researchers envision a day when bacteria will be used to efficiently treat wastewater while generating power. But don’t cancel your electric service just yet; right now the bacteria produce relatively small amounts of electricity. It would take trillions of bacteria to power a 60-watt light bulb. That’s this week’s note on emerging science, I’m Jennifer Chu.

Back to top

Eye on the Tiger

CURWOOD: With the reappearance of the Ivory-Billed Woodpecker not so long ago, the scientific community is once again wrestling with an old question: How much looking does it take to say something is gone? That's been the case with the Tasmanian tiger, considered extinct for decades. Margaret Mittelbach and Michael Crewdson became fascinated with the species and went to Tasmania, an island off the southern tip of Australia, to search for the creature. The two scientists wrote about their journey in the new book, “Carnivorous Nights: On the Trail for the Tasmanian Tiger”. Margaret Mittelbach joins me now, and Margaret, reading your book, I was surprised to learn that your search for the Tasmanian Tiger actually begins in Manhattan of all places.

MITTELBACH: Our search really began at the American Museum of Natural History. They have a wonderful taxidermy of a Tasmanian tiger there and my co-author and I had seen this animal in a glass case there and it’s just spectacular. It’s got the body of a wolf or some kind of canine with a sandy colored coat, but it has striped tiger and it also has a pouch to carry its young like a kangaroo. So it’s this very unusual creature, not something you’d normally see and we decided to find out more about it. The thing that really tipped us over the edge was one day we went to the museum and the glass case was empty and a librarian told us the tiger had been moved to an exhibit on genomics. A museum in Australia was very seriously attempting to extract DNA from their own specimens of the tiger in order to resurrect the species. And the notion was that perhaps extinction isn’t as final as it sounds. When we did further research we found out that many people in Tasmania still believe the tiger existed, even though it had been labeled extinct and frequently went looking for it and some people have actually devoted their lives to searching for it. So that was further impetus to see where this animal was. It seemed to be in some kind of state of limbo, either in the past, or maybe even in the future, but where was it now, let’s go find out.

CURWOOD: I want to find out about your journey to find out, but first tell me biologically, what is the Tasmanian tiger?

MITTELBACH: Its scientific name is Thylacinus Cynocephalus, which means pouched animal with a dog head. It’s a carnivorous marsupial, the largest carnivorous marsupial in the world, so even though it looks a little bit like a canine, it’s not related to a dog or any placental species closely. It’s more closely related to kangaroos and other marsupials.

CURWOOD: What was the last known Tasmanian tiger seen alive out in the wild?

MITTELBACH: The last Tasmanian tiger that was known to have existed actually died at a zoo in Hobart, Tasmania’s capital in 1936. Since then there have been many sightings in the wild, but none of them have been verified. That said, in the early 1980s a very well-respected wildlife biologist in Tasmania, Hans Narding, saw a Tasmanian tiger at night and he observed it for three minutes. He wasn’t able to take a photograph, but his sighting led to a two-year long search of the area where he saw it and unfortunately, they didn’t find any evidence of the tiger after that, but most biologists in Tasmania believe that his sighting was real.

CURWOOD: Just for the moment assuming that it is extinct, what would have driven it to extinction?

MITTELBACH: When Tasmania was first settled by the British in the early part of the 19th century, they set up a large sheep farming industry and Tasmanian tigers occasionally preyed on the livestock and this disturbed the farmers down there. So they lobbied the government to set up a bounty to put on the thylacine’s head and that was finally done in 1888 and they paid one pound sterling for every dead tiger. So killing tigers basically became a business. One pound sterling was a lot of money back then, probably a week’s wages and over the next 30, 40 years tigers became increasingly rare and so it was basically hunted to extinction.

CURWOOD: So you take off for Tasmania and what are you hoping to get out of this trip? There are pretty big odds that you’re not going to come face to face with a thylacine if the people who have been there hunting it for decades haven’t been able to find it.

MITTELBACH: Right, our expectations of actually seeing a thylacine were very low when we left New York. But what we did hope to see and certainly did see were all of the amazing animals that survive in Tasmania. Some of those include the Tasmanian devil, which is an amazing little creature. It’s of course known from the cartoon, but it’s a real animal too. And we met this great guy, Jeff King, who used to be a cattle rancher and he ended up becoming a conservationist and turning his entire property into a wildlife preserve and occasionally he takes people to see Tasmanian devils in the wild. He actually collects roadkill, dead wallabies, which are small kangaroos that have been killed by cars, and he takes them to his barn and puts them in his freezer. Then when he decides he wants to go see a Tasmanian devil, he defrosts the wallaby, ties it with a rope to the back of his pickup truck and then drags it across his property to create a scent trail. So he’s basically chumming terrestrial style and the devils have an incredible sense of smell, so they will follow that trail.

And what we did with him was we went to a little house he has in the bush or fishing shack that he uses as a blind and he stakes out a dead wallaby in front of a window. You go there before sunset and then you wait until darkness falls and eventually Tasmanian devils will come down to the carcass to feed and it’s just an amazing sight. They are about the size of a bulldog and they look a little bit like a black bear cut off at the knees. They have short black fur and these sort of hairless snouts and they start to get to work on the carcass and they have huge heads and powerful jaws and when they fight to get a better position on the carcass, it’s really a creepy scene and you just get this chill going down your back and they start whirling around and trying to bump each other off the carcass. It looks like a barroom brawl.

[LAUGHTER]

CURWOOD: So let’s talk about the tiger hunters. Tell me, who are these people and what makes them go out day after day to track what might be just little more than just a ghost of a species?

MITTELBACH: They just have incredible faith that animals are resilient and some of the tiger hunters, they either have heard the animal many, many years ago crying in the bush or they believe they’ve seen it.

CURWOOD: You say some people have heard the cry of a Tasmanian tiger, what is that sound?

MITTELBACH: They make a variety of sounds, but the one that people describe most and then will demonstrate for you is this kind of “yip, yip” cry. And they also make a coughing bark.

CURWOOD: Margaret, in your book there’s a part where Col Bailey, whom you describe as a true believer in the Tasmanian tiger, takes you to a place where he believes the tiger still roams. I’m wondering if you could read from this please?

MITTELBACH: Sure. “We walked silently until Col found an animal trail and turned off. He motioned for us to go ahead of him, and parted some woody shrubs for us to take a look. Through the green brush, we could see a sunken plain surrounded by low wooded hills. It looked like a vast natural amphitheater. “It’s a very rare find when you get something like this,” Col said in a low voice. “This is all natural. It’s never been cleared. We’re thirty miles from the nearest town.”

In the foreground, the green and tan grasses of a marsupial lawn had been nibbled down by wallabies and wombats. On the horizon, rugged mountains of bare rock gleamed white in the sunshine. “There’s the Tiger Range,” said Col. “They hide up there during the day and come down to hunt at night. They’ll creep along through these grasses and pounce on a wallaby.”

We had gotten so used to the pattern of the animals in Tasmania, invisible during the day and abundant at night, that the thought of a thylacine emerging from the wooded hills to dispatch a wallaby seemed entirely plausible. The wild landscape, the ghost town, and the hot breath of the leatherwood-scented wind were working their magic.

We closed our eyes and mouthed, “We do believe in thylacines. We do believe in thylacines.” When we opened them, we half expected to see a Tasmanian tiger standing in front of us. But the natural amphitheater remained empty.”

CURWOOD: Sounds like at this point, you’re getting kind of obsessed with these.

MITTELBACH: Well, I think we started out being obsessed and got even more so as we were there because just as you meet people who tell you they’ve seen tigers, they’ve heard tigers, and about half the people in Tasmania, I think, believe that tigers are still out there. You start to believe, well maybe there are, maybe I’ll see one and your hopes start to rise enormously. When the ivory-billed woodpecker was rediscovered that was almost like a holiday or Christmas Day to me, and people have quoted Emily Dickinson’s poem, that “hope is the thing with feathers.” And I think the ivory-bill has proved that that’s true. But my co-author Michael and I like to say “hope is the thing with stripes,” and who knows, if the Tasmanian tiger is rediscovered someday that would be very exciting. We hope that it is. Whether it will be, we don’t know.

CURWOOD: Margaret Mittelbach and Michael Crewdson are co-authors of “Carnivorous Nights: On the Trail of the Tasmanian Tiger”. Thanks for taking this time with me today Margaret.

MITTELBACH: Oh, thanks Steve.

Related links:
- Parks and Wildlife Service Tasmania - Wildlife of Tasmania - Thylacine
- “Carnivorous Nights – On the Trail of the Tasmanian Tiger”
- Australia Museum Online - Cloning Australia's Thylacine

Back to top

[“BLUE SEPTEMBER” TILLMAN & AMBIENT GROOVE ARTISTS: LINGO (MUSICA HELVETICA) 1997]

CURWOOD: Coming up, a high school lesson in recycling. Keep listening to Living on Earth

ANNOUNCER: Support for NPR comes from NPR stations, and the Charles Stewart Mott Foundation, online at mott dot org, supporting efforts to promote a just, equitable, and sustainable society; the Kresge Foundation, building the capacity of nonprofit organizations through challenge grants since 1924. On the web at kresge dot org; the Annenberg Fund for excellence in communications and education; and at the W.K. Kellogg Foundation, from vision to innovative impact, 75 years of philanthropy. This is NPR, National Public Radio.

[“COUNTERWEIGHT” FONTANELLE: FONTANELLE (KRANKY) NO DATE]

Paper Trail

CURWOOD: It’s Living on Earth. I’m Steve Curwood and coming up: invasive species, friends, foes, or folly? But first, the average New Hampshire resident produces about five pounds of trash a day. Now, that's less than just a few years ago, thanks to lighter bottles and plastic cans, and recycling. Back in 2001, faced with a growing scarcity of landfills, the state initiated a recycling program. But, two years later, it was eliminated for budgetary reasons. As part of Living on Earth’s ecological literacy project, Carey Crossman reports on a new recycling effort underway at his high school in Claremont.

[BANGING ON BINS]

CROSSMAN: It's Monday afternoon, and some student volunteers at Stevens High are running down the halls and into classrooms, coming out and carrying blue and clear plastic bins.

[RUSTLING PAPER IN BINS]

CROSSMAN: The students dump the bins loaded with paper into even bigger bins, and these are emptied into a dump truck, which takes the paper to a huge trailer behind Claremont's middle school.

MAN: Have a good day. Thank you for giving me all this paper and cardboard.

[STARTS IGNITION]

CROSSMAN: Once the trailer is full, it holds about 5 tons, it's hauled to a recycling plant in Billerica, Massachusetts.

[TRUCK DRIVES AWAY]

CROSSMAN: For Stevens High science teacher Joanna Bitter, this is a scene she couldn't have imagined just a few years ago when she first tried to bring recycling to the school.

BITTER: It didn't work out. It worked for the first spring semester we did it, and over the summer, our garbage cans which we had been using for our recycling cans became part of the janitor supplies and disappeared.

CROSSMAN: And so teachers and students just continued to throw their paper, plastic and cans into the trash, until 2003, when the school librarian decided to act.

FREELAND: I was appalled at the amount of paper, particularly in the library, that was going into the garbage cans.

CROSSMAN: Kate Freeland is a librarian at Stevens High.

FREELAND: I recycle at home, it's important to me, and it hurt me every time I picked up 20 pages that came out of the printer that no one claimed, and threw them into the garbage. So I decided to go ahead.

[BACKGROUND NOISES, THUMP OF NEWSPAPERS INTO BIN]

CROSSMAN: Kate Freeland takes a weeks' worth of newspaper and throws it into one of the recycling bins in the library. It was Freeland who initiated a new effort to get the school to recycle. But this time, no cans, no bottles, just paper.

FREELAND: And I got the permission of the administration to go ahead. They were enthusiastic but not encouraging, because of the experience they had had before.

CROSSMAN: Kate Freeland searched the Internet, and found the NRRA, The Northeast Resource Recovery Association. Based in Chichester, it's a co-op that provides members with information and helps with the logistics of recycling. 170 New Hampshire schools are members, and Freeland decided to join. But finding volunteers to help put the program into practice was tough. The librarian even had to use her own car to take the paper to the collection place. Fortunately, social studies teacher Jill Chasteny shared Freeland's enthusiasm.

CHASTENY: I've been recycling on my own for a long time, since probably late high school, and I've just continued to do it in my personal life, and one of my goals when I got my job here was to get recycling going in this building.

CROSSMAN: Jill Chasteny says slowly but surely, participation in the school's recycling project grew. But there were some teachers who thought it was a waste of time and energy. Especially history teacher Rod Minkler.

MINKLER: I don't have the urge and the need to recycle, I don't believe in the process. I think a lot of it is just making people feel good about themselves and I don't see much end result.

CHASTENY: (laughs) You talked to Rod, didn't you? What he probably hasn't told you is that he secretly, or sometimes quietly, does come over here with piles of paper and puts it in my recycling bin on occasion.

CROSSMAN: All that paper adds up. Every few weeks, librarian Kate Freeland receives a check from the NRRA. The amount depends upon the going rate for recycled paper. The money, 115 dollars after expenses so far, goes into the school's general fund.

[DOORS OPEN, RUSTLING PAPER]

CROSSMAN: There are also benefits beyond the money and reducing pollution. While many student volunteers say they only work on the recycling project because they have to do community service in order to graduate, some, like eleventh grade student Amanda Adams, says the project has changed her attitude.

ADAMS: I like it a lot, it's really fun. I enjoy this a lot better than staying home and watching TV. I can see it's really working, I mean, look at the stacks of cardboard. It's overflowing the hallway. It's great. We're finally getting rid of some of this stuff and it's not going to the dump.

CROSSMAN: Last year, the schools participating in the Northeast Resource Recovery Association recycled nearly 25,000 tons of paper. And if Kate Freeland had her way, soon there could be more.

FREELAND: So we have gotten a commitment from the district to supply district maintenance trucks to, and personnel, to move the paper. That's a huge step. My car is no longer needed every week, or Jill's. And as we move more toward district responsibility and less toward Kate and Jill responsibility, I see this just going on. It becomes a Claremont School District program, and not a Stevens High School program.

CROSSMAN: For Living on Earth, I'm Carey Crossman in Claremont, New Hampshire.

Back to top

[“UNCERTAINTY PRINCIPLE” TILLMAN & AMBIENT GROOVE ARTISTS: LINGO (MUSICA HELVETICA)]

Ecological Intruders

CURWOOD: Evolution, the way Charles Darwin saw it, is something that takes place over millennia. But once humans started farming and moving around the planet, we started shuffling species at a far faster rate than natural selection. In North America you might think the songbirds in your yard nesting in the Norway Maple are part of a natural scene. But both the tree and many of our songbirds were brought here by Europeans who wanted to “beautify” the new world. Most of the crops we grow here are non-native as well. And some of the species that humans have scattered are so downright unwelcome, such as the fire ant, killer bee and kudzu plant, that we call them invasives. Alan Burdick is the senior editor at Discover Magazine and author of "Out of Eden, An Odyssey of Ecological Invasion." He begins his book with a story of a snake that invaded the island of Guam at the end of World War II.

BURDICK: Fifty years ago, Guam, which is an island way out in the Pacific, had no snakes whatsoever. And then, after World War II, when a lot of wartime surplus was being shipped back to Guam, this snake, originally from Australia, called the brown tree snake, snuck in. And quietly over the course of fifty years it spread and multiplied to the extent that Guam now has more snakes per square mile than anywhere else in the world. And the snake has eaten all the birds on the island, more or less, and fairly radically changed the ecosystem there.

CURWOOD: Tell me a bit about the snake, poisonous?

BURDICK: Slightly venomous, with a bite about the equivalent of a bee sting. In the native range of Australia it is a pretty bit player. It grows to about three feet long and there are a lot bigger, meaner snakes and in fact, its main predator in Australia, things like the king cobra. But on Guam, where it has no predators, it grows up to 12 feet long and it does things that no snake has ever been seen to do before like eat garbage. It’ll eat raw hamburger; it’ll eat the foam plate that raw hamburger comes on. We think of snakes typically as predators, but in this case it’s become a scavenger. I mean, it’s like a rat.

CURWOOD: So how is it the snake shows up on the island of Guam and manages to eat all the birds? How does that work?

BURDICK: This is a snake that’s a predatory snake and it’s placed on an island where, pardon me, the birds have by and large existed without predators for all of their evolutionary lives. So they don’t have the usual kind of evolutionary adaptations to things like snakes, you know, so they kind of sleep unprotected at night and were fairly easy prey. And there really are maybe two species left of the 13 species that Guam once had.

CURWOOD: Now usually though if one creature moves into fresh territory and starts eating something novel, it eats up its food supply and it perishes itself.

BURDICK: Well, the snake eats all the birds. As a consequence the insect population explodes, more insects more spiders. Actually if you walk through the forest these days you don’t hear any birdsong, which is weird enough, but the forest is filled with spider webs. It’s very creepy. So meanwhile the population of lizards also explodes because now they’re eating all the insects. And now these reptiles have become the primary food base for the snake.

CURWOOD: One of the scientists you visited there at the U.S. Brown Tree Snake Research program at one point sets up a camera to monitor snakes. He’s Gad Perry, and, well, why don’t you just read from that section. Could you Allen?

BURDICK: Sure. Maybe I should preface it by saying that Perry and his colleague have set up an elaborate experiment of all these little cubicles, each with a video camera at the top, and in the cubicle each one has a snake and kind of a test set-up with a barrier that they’re trying to perfect against the movement of the snake.

[EXCERPT FROM BOOK] “Perry’s favorite tape is dated April 21, 1995. He slipped it into the video player and fast-forwarded to 9:08pm. A bird’s eye view appeared of cubicle number one, an early test model featuring a one-meter tall barrier with a single electrified wire running along the top. On the floor, in total darkness, Honker, a very large brown tree snake, was considering the possible avenues of escape. The snake crawled up to the barrier and rose onto its tail like a charmed cobra. Its actions might have appeared sinister had the tape not been playing at double speed. Instead the events had a Chaplinesque quality. At last, with its head alone, the snake found purchase on the ledge above the wire and in no time it pulled up the rest of its body, oblivious to the principles of electricity. Earlier when Perry had exhibited cubicle number one with the lights on, he pointed out a piece of masking tape to me that had recently been laid to cover the hairline crevice that runs from floor to ceiling along the edge of the door. The need for this tape was now clear. Stretching over from its ledge, the snake pressed its body against this narrow crack and using an impossibly slim door hinge for leverage, climbed the wall vertically out of camera range. It was at this point the video image began to shake violently. The snake had begun climbing the electrical cable, leading to the camera. Suddenly an enormous reptilian head loomed on screen, out of focus, tongue flicking. The head disappeared, the long body trailed past the camera, the tip of the tail came and went, time 9:17pm. “Well,” Perry said, “we learned from that.””

CURWOOD: (laughter) I guess so. Now you once wrote a piece in Discover, I think it’s probably the seminal idea for your book. It says, “The Truth about Invasive Species: How to stop worrying and learn to love ecological intruders.” I’m sure you’ve gotten a fair amount of flak about that, why do you suppose that is?

BURDICK: There are two important facts about alien species. One of which many of us know and another which is less talked about. And the first one being, you know, we know that organisms like the brown tree snake and the zebra muscle, just a handful of these species, can have very widespread important, expensive impacts and that they deserve our attention. At the same time there are a great many species that don’t have impacts and that’s actually interesting and it’s not really discussed and it’s interesting because it reveals, you know, certain truths about how ecosystems work and don’t work and about our very complicated relationship to nature. I mean, I’m not saying alien species are a dumb issue, we should kind of shrug our shoulders and stop funding policy that prevents their spread. I am frankly just trying to have a little bit of fun, if that’s possible to do with the subject, and say, you know, let’s kind of stop demonizing them and try to understand why these invaders move around, and use these organisms as a kind of a prism to understand the very contradictory demands that we place on nature.

CURWOOD: Towards the end of your book you talk about traveling into space, and one of the most fascinating questions here is about exporting our life forms to other bodies out there in the universe. How difficult is it for us to send a spacecraft to other planets and places without sending our life forms, the little ones I’m thinking of, the microbes?

BURDICK: It is surprisingly difficult. I spent some quality time with a microbiologist at the Jet Propulsion Lab out in Pasadena, and this guy works in the spacecraft assembly facility where they build, well they built the Mars Rovers that are now out there on Mars. And this guy, his job is to kind of inspect what’s left over and to see well, gosh, did any microbes survive the incredibly kind of harsh decontamination process that we’ve devised to get rid of them? And to his great surprise they have, and he’s found at least one microbe that not only thrives in the spacecraft assembly facility, but seems to have actually evolved in it. It’s a tough little spore, it eats aluminum. He found it growing on the surface of one of the Mars Rovers. It forms these spores and then the spores kind of group together to form a little, what he calls an igloo. It looks kind of like a macaroon under a microscope and when he cuts it open and exposes it to the light detection techniques that NASA’s developed to look for life, he finds no sign of life and then when he puts this little igloo back together, the microbe comes back to life amazingly. And I asked him, “So you know you found this thing on the Mars Rover when it was being built. Do you think it’s up there on Mars right now?” And he said, “oh yes, I’m quite certain, I’m almost certain that it is.” So you know, I mean, it’s just indicative of how life wants to spread. Either they’re moving around inadvertently with us or they’re moving around intentionally with us, but they are kind of reflections of our ambition, our desire to reshape the nature around us in a way that makes us more comfortable.

You know, we can kind of demonize these things, but in a way they’re really kind of impressive little critters. They’re sort of doing what nature permitted them to do. And in a Darwinian sense, I mean, they’re winners. I mean you’ve got to be, even if you don’t like aliens, and there is quite a number of reasons not to, I think it’s worthwhile sort of stopping and at least being impressed by their ability to thrive in a world that we think that we dominate. So far as we know, Earth is the only planet with life on it and the wind is blowing outward. We may well be the dandelion in the solar system.

CURWOOD: I was speaking with Allen Burdick of Discover magazine. His book is called "Out of Eden: An Odyssey of Ecological Invasion." Allen, thanks so much for taking this time with me today.

BURDICK: My pleasure, thank you.

Related link:
“Out of Eden” by Alan Burdick

Back to top

[“DANCA DAS CABECAS” PAUL HORN: THE ALTITUDE OF THE SUN (BLACK SUN) 1989]

CURWOOD: Next week on Living on Earth. As the demand for natural gas keeps rising, there’s a need for a huge expansion of the facilities that handle liquefied natural gas from abroad. The trouble is, an industrial accident or terrorist attack could touch off a fireball of catastrophic proportions.

MAN: Within two-thirds of a mile, people would suffer severe pain within ten seconds, second degree burns within thirty seconds, and third degree burns within forty seconds of a vapor cloud ignition that could come from a hole in the tanker ship or something that would happen on site. That is not something that people should be subjected to. There are nine thousand people that live within one mile of this proposed facility.

CURWOOD: LNG and public safety, next time on Living on Earth.

[BIRD SONG]

CURWOOD: And now, for a moment down under, but hopefully uplifted with the distinctive song of one of Australia’s great improvisers.

[BIRD SONG]

CURWOOD: This is a pied butcher bird as recorded by David Lumsdaine.

[EARTHEAR: LUMSDAINE, BUTCHERBIRD403.MP3]

CURWOOD: Living on Earth is produced by the World Media Foundation. Our crew includes Eileen Bolinsky, Jennifer Chu, Steve Gregory, and Susan Shepherd, with help from Jennie Cecil Moore and Kelley Cronin. Our interns are Max Thelander and Sarah Williams. Allison Dean composed out themes. And this week, we wish a fond farewell to our technical director, Paul Webrek. Thanks Paul. You can find us at living on earth dot org. I'm Steve Curwood. Thanks for listening.

ANNOUNCER1: Funding for Living on Earth comes from the National Science Foundation, supporting coverage of emerging science; and Stonyfield Farm. Organic yogurt, and smoothies. Stonyfield pays its farmers not to use artificial growth hormones on their cows. Details at Stonyfield dot com. Support also comes from NPR member stations, and the Ford Foundation, for reporting on U.S. environment and development issues, and the Wellborn Ecology Fund.

ANNOUNCER2: This is NPR, National Public Radio.