You're listening to Talk of the Nation: Science Friday. I'm Ira Flatow. If we could turn back the clock 65 billion years ago, what would we see? Well, wouldn't we like to save some of those dinosaurs that were dying out around then and other species that were perishing during that mass extinction?

And if you're still dreaming of dinos, my next guest might say, wake up, because the amphibians now need you. New research published in the Journal of Proceedings of the National Academy of Sciences suggests the rapid frog die-offs and other species declines we are witnessing now could be harbingers of a sixth mass extinction that could be happening, and it would be a grim picture.

Well, my next guest says there are actions we can take to cut our losses, and joining me now to talk about it is Dr. Paul Ehrlich, president of the Center for Conservation Biology, also professor of population studies at Stanford, and author of the new book, "The Dominant Animal: Human Evolution and the Environment." Welcome back to Science Friday.

Dr. PAUL EHRLICH (President, Center for Conservation Biology, Professor, Population Studies, Stanford University; Author, "The Dominant Animal: Human Evolution and the Environment"): It's nice to be back, Ira.

FLATOW: This - just reading from the title of your paper here, says where does biodiversity go from here? A grim business as usual forecast and a hopeful portfolio of partial solutions. A grim business as usual.

Dr. EHRLICH: Well, we are in the middle of the sixth-grade extinction. Many people are confused to think that the only problem is loss of species, but, of course, everybody who understands that the other organisms of the planet are the working parts of our life support systems, also understands that the loss of populations, that is, the reduction in the ranges of species is equally or in some cases more important.

A good example is the honeybees we have over here came originally from Italy. If you had one population of honey bees around Rome that was going to be there forever, you would not have lost any species diversity, but of course, if all the honeybees were going from North America, we would lose billions of dollars and lot of wonderful food that we depend on, because they pollinate our crops.

So - and of course, as you may know, we're already in trouble with the honeybees. So the mass extinction is a very serious problem, and what's worse is, when you look at it, we are not doing anything about it.

FLATOW: Mm-hm.

Dr. EHRLICH: We are continuing all the things that are contributing to the extinction.

FLATOW: And you write that, quote, "because that outlook is bleaker than we are willing to accept, we can then outline a more hopeful set of answers." Things are worse than people are telling us?

Dr. EHRLICH: I think they're much worse, because there hasn't been enough attention paid to the loss of populations, which is just beginning to attract attention. We're just beginning to understand how incredibly diverse those populations are, and how very important that is when we're facing a period of probably incredibly rapid climate change.

All the news is indicating that the IPCC estimates were much too conservative. You may have seen even today the arctic ice is melting much faster than expected. And of course, they explain - now expect an ice-free arctic in about five years.

And that means the planet's going to heat even more, that lots of organisms in the arctic are going to start dying off, like we've already heard about the polar bears. And the climate is going to change even more rapidly, because the arctic - it functions in the climate system in a very important way.

So, all those changes are going to make it harder for the biodiversity to persist, for our crops to be pollinated, for our crops to be protected, and so on. And on top of that, of course, we have already probably entrained(ph) almost a thousand years of relatively rapid change in patterns of precipitation.

And guess what, you know, what we're depended upon for our foods is where the rain falls, and as that changes, we're going to be chasing it, and it's going to be tough.

FLATOW: Mm-hm. So, even though that you've - you are the grim reaper here, giving us this bad news, you do say, there's a hopeful side of all of this. There are steps we could take.

Dr. EHRLICH: Well, you know, when people ask me whether I'm an optimist or a pessimist, I tend to say, I'm optimistic, although not as much I used to be about what we could do.

FLATOW: Mm-hm.

Dr. EHRLICH: I'm very pessimistic about what we will do. In other words, it's like Al Gore's saying, that in 10 years, we could get largely off the fossil-fuel standard for at least running our electricity system.

Well, that's perfectly correct. I think Al is right, but it would require a World War II type mobilization, and we need the same kind of mobilization to save the working parts of our life support systems. And there's no single silver bullet, but there's a whole array of things that we could do, that would make the future much more optimistic.

I mean, one of the things we talk about in the scientific community, always talks about, is bringing population growth to a halt as soon as possible, and starting as slow decline. And yet today, or I guess yesterday in the newspapers, they were bragging about how the United States is going to be 439 million people by 2050.

That's roughly 300 million people more than anybody has ever given a reason for having alive in the United States at one time. Just think about it, another 137 million people in the U.S. competing for all the necessary things that the working parts of our life support systems, the biodiversity also needs, you know.


Dr. EHRLICH: When we pave over things, we lose biodiversity, we add toxins to the planet, and not only do we threaten ourselves, we lose biodiversity. We change our climate rapidly, not only does that threaten our health in many ways, but we lose biodiversity, and again, the biodiversity is what's giving us food, maintaining the proper quality of the atmosphere, preventing floods, and on, and on.

FLATOW: Mm-hm. This paper really seems like a call to scientists to get down from their ivory towers and talk about these issues. I have had scie - I've mentioned this on the program before. I've had scientists who have pulled me over to the side and said in private, much the - what you're saying, the situation is much worse than we're willing to talk about in public, because we don't want to scare people.

Dr. EHRLICH: Well, I think people need to be scared. I think that when Americans said - I - there are very advantages to getting older. But one of them is, you can remember things historically.

FLATOW: Mm-hm.

Dr. EHRLICH: And I remember the way the country organized after Pearl Harbor, you know. Americans got scared, Americans got together, Americans changed their entire economy in basically a year.

I mean, you know, 1941, we're producing hundreds of thousands of automobiles. 1942, we're producing hundreds of thousands of tanks, and airplanes, and battleships, and so on, and so forth. You can do it, if you have the right incentive, and fear is...

FLATOW: Mm-hm.

Dr. EHRLICH: Ought to be a big incentive now if we care anything about our children and grandchildren's world. That's the crucial thing. In other words, you and I probably will - people around the world are already in trouble, because of for instance climate change, but not here.

FLATOW: Mm-hm.

Dr. EHRLICH: And sea level will rise, but we'll be able to out walk it.

FLATOW: Mm-hm.

Dr. EHRLICH: But in terms of what's going to happen to our kids and grandkids, then we have a totally different story, and there's a lot of reasons to be extremely scared for them.

FLATOW: If scientists do - are scared enough. What about none scientists who want to help preserve biodiversity? What should the rest of us do?

Dr. EHRLICH: Well, there - one of the things is get politically active. In other words, we're having a campaign for president, were you get issues coming up that in the big picture are absolutely trivial. Should gays be able to get married? What movie starlet is wearing her panties? Who had an affair, and so on, and so forth.

Have you heard anything about ecosystem services? Have you heard any real plans to do something serious about the climate situation? I mean the big debate that's related to climate is where should we drill for oil. And, of course, the scientific answer is nowhere. And as any economist will tell you, gasoline is too cheap.

We need to raise the price of gasoline, and get off of the gasoline, the oil standard. But the debate is insane, it says, where should we drill? Should we drill in ANWAR? We shouldn't drill in a waste land. We've already discovered more than enough oil, that if we burn it, we're likely to just, you know, ruin the climate for our children or our grandchildren completely.

FLATOW: Mm-hm.

Dr. EHRLICH: And so, one of the things to do, get politically active, write to your politicians. Vote, and vote for the right people. And I don't have to tell you who that is these days, because we have now suffered through eight years of an administration that has fought very hard to keep science out of the news, to counter all the scientific information we have, to destroy the Endangered Species Act, which is inadequate.

But it's all we've got, so you know, learn about it, don't necessarily listen to me, I could be a - you know, a paid agent of the contraceptive industry or something. Learn about it, there are lots of places you can learn about it, and then take political actions.

FLATOW: Mm-hm.

Dr. EHRLICH: That's a starter.

FLATOW: Mm-hm. 1-800-989-8255, talking with Dr. Paul Ehrlich, author of "The Dominant Animal: Human Evolution and the Environment." Let's go to the phones. To Roger in Cleveland. Hi, Roger.

ROGER (Caller): Hi, Ira. Hi, Paul. How are you doing today?

Dr. EHRLICH: Hi. It's a very nice day here in California.

ROGER: Well, up here in Cleveland, it's kind of hot and sunny, but that's OK.

FLATOW: Get used to it.

ROGER: Yeah, yeah.

(Soundbite of laughter)

ROGER: Listen, I'm a crayfish-conservation biologist and I've been - I've worked in aquatic ecology for 30 years. And I just wanted to bring out the point that almost 50 percent of the crayfish here in the United States and Canada are in need of some conservation attention.

In terms of three big groups in aquatic systems, the fish, the bivalves - the bivalve mussels, and the crayfish, on average, about 33 percent of the species in those three groups are endangered. And I just finished participating in a court case where there was a species of crayfish found in a small drainage base in about a couple of square miles, very, very small and someone wants to dig a big old mine right in the middle of its habitat. And the state of Tennessee couldn't stop them from doing it. So, our environmental laws are really - they're empty. They're not doing much. We have laws, but they're ineffective.

Dr. EHRLICH: They're ineffective, and the Bush administration has been struggling very hard to make them less effective. And as you know, when we talked to any specialist in any group, I mean, for instance, I did a lot of my work on evolution in butterflies, and you go back to place after place where there used to be populations, they're gone. In the oceans, if we're going to get wet, the number of oxygen-starved dead zones in the coastal waters has about doubled every decade since the 1960s killing off populations of fish, crabs, other marine life. And we're just doing this all over the world, and we can't do without these organisms. Thank you for calling and pointing out to me that I often neglected to talk about fresh water organisms which are some of the most endangered in our country and around the world.

FLATOW: Thank you, Roger. Let's go to Sarah in Good Thunder, Minnesota. Hi, Sarah.

SARAH (Caller): Hi.


SARAH: Thanks for having me. It's a great conversation. I'm just calling to comment that in Minnesota where the mosquitoes should be prevalent, I noticed on my farm in the last three years, there'd been bursts of mosquitoes in the spring, followed by nothing, and the frog populations are down. I used to, you know, work out in the garden all year long or out summer long with a mosquito repellent. I haven't bought any four years. So, what's happening? I know that this administration and many local - has the USDA, you know, said that farmers don't have to report the pesticides that they're using now. I believe that was in the paper the other day. I just - you're right about changing administrations or leaders that go against our natural environment, and it's going to leave us, you know, in a death row.

Dr. EHRLICH: Well, the frogs are particularly worrying because to mix my metaphors, they sort of can be the canary in the mine because they're dependent on both aquatic and terrestrial habitats, most of them, and they breathe through their skins and they're very sensitive to everything from the toxics, which we release in gigantic amounts, the pesticides, herbicides, and just the industrial chemicals in general. And they're also very sensitive to ultraviolet light, which of course we've had problems with because of the partial depletion of the ozone layer.

So, we're not sure why the frogs are disappearing. But all of the scientist who looked at it are very worried. I should point out, by the way, that I am a crazy ecologist. But I'm actually expressing on a general picture of which way - where humanity is going, the grim business as usual forecast. I am speaking for the entire scientific community. Go to www.dominantanimal - written as one word - dot org and click on further information, and you'll see the statements that were put out by 58 academies of science in 1993 and the world scientist's warning the humanity which was signed by more than 1500 scientist including more than half of the living Nobel laureates all saying, if we don't change our ways, we're going to get down the drain and that attracted no attention, and it's still the view of the scientific community.

FLATOW: We're talking with Dr. Paul Ehrlich, author of the "Dominant Animal: Human Evolution and the Environment" on Talk of the Nation, Science Friday from NPR News. I'm Ira Flatow. Does the fact that Europe at least is a little greener-thinking than we are give you any hope?

Dr. EHRLICH: Well, that gives me - listen, there are a lot of reasons for hope if we do something, and one of the things that most hopeful about Europe is, of course, that their birth rates are way down. And where you want to see birth rates way down, of course, is in the richest countries because they are the ones whose levels of consumption put most of the pressure on the planet's environmental system. And so we could easily - we ought to be imitating what's going on in Europe. Instead, we're the most over populated country in the world.

The third largest in actual numbers of people, but of course, when you factor in our huge levels of consumption, we're way behind beyond China and India in our impact on the planet. And we're still growing like a sky rocket and we don't - unlike most poor countries, we don't even have a population policy. I mean, in United States, we argue about migration immigration policy without having a population policy. It's kind of like saying to somebody, design me an airplane that'll load 100 people a minute. And when you say, well, how many should it fly with? You say, well, don't worry about that - just one little, you know, load a 100 people a minute.'

FLATOW: But doesn't the expansion of China, both economically and the population wise concern you?

Dr. EHRLICH: Oh, it certainly does.

FLATOW: Does that concern you?

Dr. EHRLICH: I think. In 1972, a political scientist colleague and I wrote an op-ed for the New York Times saying, "What if All the Chinese had Wheels?" Asking what would happen with the planet's environment if the five - then 500 million Chinese started getting interested in cars. Now, we have 1.3 billion Chinese who are getting interested in cars. They're soon going to pass us as a polluter in many areas. They're virtually out of water. There's essentially no potable water in the country. One of the reasons their rain is so acid is that they keep coal fires going all the time to boil their water. They're building coal-fired power plant which is the worst possible thing you can do in terms of climate change at an incredible rate several a week.

So, yes I'm extremely concerned about China. But you know, It's hard for an American to talk about what China should be doing when we're doing the opposite. And we set a terrible example for the world. In this like it's very hard to criticize politicians for not getting on top of these problems when still many of our colleagues in science are still sticking to their experiments and not worrying about the world coming to an end.

FLATOW: Though yet, you still want to keep a hopeful attitude about this.

Mr. EHRLICH: Yes because there's so many things we could do. And one of the reasons to be hopeful is the reasons we don't fully understand. Societies can change extremely rapidly in their behavior and attitude. So if you remember in the 1960s, we changed the United States dramatically in terms of race relations late '50s and '60s. Birth rates change quite rapidly in the United States in the early '70s, and the best recent example is nobody that I know expected the Soviet Union and Communism to collapse in the 1990s, but they did. So, one can hope that when the time is right, we will change our attitudes both on how we treat our environment and something that's total - tightly tied to what how we treat each other. And if we do that and do it rapidly then I think our kids could have - and our grandkids, particularly, could have a wonderful world.

FLATOW: All right. That's a good thought to end the week on Dr. Ehrlich. Thank you for taking time to be with us.

Mr. EHRLICH: All right. Nice talking to you.

FLATOW: Paul Ehrlich, president of the Center for Conservation Biology. Also professor of Population Studies at Stanford and author of the new book "The Dominant Animal: Human Evolution and the Environment." We're going to take a break and come back and change the mood altogether. We're going to talk about Physics and about possibility of bending light backwards. Sounds like science fiction, well it's something that's entering in the realm of science fact. So interesting new studies about bending lights. Stay with us, we'll talk about it.

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