MARGARET WARNER: The National Academy of Sciences has launched a campaign to urge the teaching of evolution in the nation's schools. Academy President Bruce Alberts explained why at a press conference earlier this month.

BRUCE ALBERTS: The National Academy of Sciences and our affiliated organizations have long been concerned with science education. We feel it's a very important element of our society, and that we have a ways to go--an important challenge to really improve the education we provide in science to our young people and the public understanding of science more generally. Particularly, this issue today reflects our concern about the failure to teach evolution adequately in our schools and the failure to understand why this is a important issue.

MARGARET WARNER: The main tool in this campaign is a new guidebook--called "Teaching About Evolution and the Nature of Science"--which the Academy is sending to science teachers and state science supervisors around the country. The guidebook's authors, a group of prominent scientists and educators, concluded that "many students receive little or no exposure to the most important concept in modern biology, a concept essential to understanding key aspects of living-- biological evolution."

STUDENT: He's kind of cute. Is he always going to stay yellow?

MARGARET WARNER: The guidebook is designed to help teachers integrate an understanding of the theory of evolution into their basic biology instruction for students from kindergarten through grade 12. The guidebook defines evolution this way: "evolution in the broadest sense explains what we see today is different from what existed in the past... Biological evolution concerns changes in living things during the history of life on earth. It explains that living things share common ancestors. Over time, evolutionary change gives rise to new species. Charles Darwin called this process 'descent with modification,' and it remains a good definition of biological evolution today."

In more than 140 pages, the guidebook explains the importance of teaching evolution; suggests how sensitive questions from children and parents can be answered; and outlines activities for integrating evolution into other science instruction. The guidebook maintains that a person can believe in God and still accept evolution. But more than 70 years after the historic conviction of teacher John Scopes for teaching evolution in a Tennessee school, there are still religiously-driven campaigns to limit the discussion of evolution in public schools. Many Christian conservatives believe schools should teach the biblical theory of creationism--that God created the earth, and all living things on it, in six days. Many others argue that creationism should at least be offered along with evolution as equally valid theories about the origins of life on earth. In 1987, the Supreme Court struck down a Louisiana law that had required any public school teaching the theory of evolution to teach creationism as science too. The court said the law was unconstitutional because its purpose was "clearly to advance the religious viewpoint that a supernatural being created humankind." To date, 15,000 guidebooks have been given to teachers and science supervisors--and the Academy hopes to sell 25,000 more.

MARGARET WARNER: Now, four perspectives on this. Donald Kennedy is the former president of Stanford University, now an environmental sciences professor there. He headed the Academy panel that drew up the guidelines. Terry Spohn is a Biology professor and dean of the College of Arts & Sciences at Liberty University in Lynchburg, Virginia. Mark Witwer heads the science department at the Delaware County Christian School, a private school near Philadelphia; he teaches earth science. And Barbara Schulz teaches Biology at Lakeside School in Seattle and is past president of the National Association of Biology Teachers. She taught in public school for 25 years before going to Lakeside, which is private. Welcome all of you.

Donald Kennedy, sum up. How would you describe evolution in its simplest terms, and why should it be taught in schools?

DONALD KENNEDY, Stanford University: Descent with modification is a pretty good summarizing phrase. Evolution explains how from relatively simple starting points and a fairly universal scheme of fundamental biochemistry, forms evolved in time and changed and diversified into somewhere between 10 and 30 million species of plants and animals we have today. The reason why it's important to teach about evolution is that as one distinguished biologist put it 40 years ago, nothing else in biology makes sense without understand evolution.

MARGARET WARNER: Terry Spohn, nothing else in biology makes sense without understanding evolution?

TERRY SPOHN, Liberty University: Well, I view this effort as another attempt by the evolutionary community to brainwash the American public at the American taxpayer's expense. The point of the matter is that there are two possible explanations for how everything got here. One is rooted in naturalistic philosophy, which is the evolution view, and the other is that some intelligent designer created what we see about us. When Dr. Kennedy suggests that there is evidence from the fossil record for this change, that's simply not the case. Dr. Steven Jay Gould, a Harvard evolutionist in 1972, said that the fossil record was notable in two characteristics: stasis, which argues against change, that is, creatures appear on the fossil record and stay pretty much the same as they do when they disappear from the earth, and two: sudden appearance, that these creatures appear fully formed without a prior history. This argues for special creation, not evolution, and is contrary to those facts concerning the fossil record--since we have taxpayers that range from atheists to Zen Buddhists and everything in the middle, including Christians and followers of Islam, the only correct thing to do, the American thing to do, the democratic thing to do is to offer both of these models and let the students decide which one best explains origins.

MARGARET WARNER: All right. I want to get back to the validity of evolution, Terry, but can we first get Ms. Schulz's view of this, who teaches Biology. What is your sense of whether it is important or not to teach evolution in schools to children grades one through 12.

BARBARA SCHULZ, High School Biology Teacher: I think it's absolutely critical to teach evolution and to teach evolution as one of the unifying principles that help explain the diversity that we have on the planet, as well as the continuity that we have. Evolution has to be taught as a science, and science demands evidence. We cannot deal with any ideas that are based on a belief system, and, therefore, the teaching of creationism does not fit that model of what real science is. This booklet that has been produced by the National Academy I think has done a lot to enhance the teacher's position and to support the teacher by providing the prestige of the Academy and the support of the scientific community in that we are teaching science and evolution as a process and as an inquiry.

MARGARET WARNER: Mr. Witwer, what is your view of this basic debate?

MARK WITWER, High School Earth Science Teacher: Well, I come at this as a high school teacher and perhaps one of my major concerns is that although there are good things in the booklet--I read it and I like it very much and it's a good resource for explaining what evolution is all about and what it isn't--one of my concerns, though, is that a clear distinction needs to be made, and the booklet tends to downplay this, I think. It's not as clear as it needs to be for students. The distinction between the kinds of changes that we're talking about when we use the word evolution--if we say that nothing in Biology makes sense without evolution, I think what's often meant by that is that the small changes that produce variation in living things, like the different sizes and shapes of finch beaks in the Galapagos Islands, that's considered evolution and so are very, very large changes that might produce a whole different kind of living thing, such as whales from hoofed land mammals. That sort of thing is also called evolution and it's all usually or often presented as a package deal. You either accept the entire thing--both kinds of changes--or if you argue against the large changes--as creationists tend to do--you're accused of objecting to the smaller ones as well, and that's not the case. So creationists have a large reservation about the scale of the changes that the evidence in nature supports, and certainly supports strongly.

MARGARET WARNER: Mr. Kennedy, respond to both Mr. Witwer and Mr. Spohn on that point. Basically they're saying that evolution isn't--is a debatable theory as well, and why should it be presented as scientific fact, something that's absolutely essential to teaching science?

DONALD KENNEDY: Well, I can't respond to them together because I very much respected Mr. Witwer's response. He sounds like a very good teacher, and the distinction between large evolutionary steps and small ones is a problem for many students. The overwhelming consensus in the scientific community is that the same mechanisms can explain them and, in fact, we've had enormous success in finding transitional forms in the last 10 or 15 years, where formerly we lacked them, including transitional forms, in the very instance that Mr. Witwer talks about. As to the comment that--as to the equal time comment, my sense is that scientists have a deep respect for religion and for religious beliefs and that they would in no way require that students accept evolution as a substitute for those beliefs. But to understand science you have to understand evolution and at least understand the framework of logic that supports it. If on Sunday one wants to reject that, that's all right. We're not asking for equal time on Sunday.

MARGARET WARNER: Mr. Spohn, since the courts so far are saying that in public schools anyway creationism cannot be taught--I mean, that's sort of the bottom line of these decisions--are you saying then evolution shouldn't be either, or are you saying both should be taught? What are you saying exactly?

TERRY SPOHN: No. I'm saying that in the public forum where you have taxpayers that are atheists, Zen Buddhists, everything in between, these are two ideas that explain or attempt to explain how everything got here. One of the statements made in the workbook is that evolution answers or asks different questions than religion does. The problem with it is that evolution also answers those questions. They suggest to young people that everything that we see can get here by random chance processes operating on matter over a period of time. This is a very, very different conclusion, and we're talking about equal time. That is not equal time. In the public forum both models should be presented and let the students decide which one does the better job of interpreting the data. That's all I'm saying.

MARGARET WARNER: But the courts have said from a practical matter in the public schools both can't be presented, so where does that leave you?

TERRY SPOHN: Well, this is a problem with understanding the nature of belief. A number of top evolutionists are atheists. Atheism is a belief system that says there is no God. Evolutionists put themselves in a very interesting position these days. According to our understanding of modern genetics, evolution in terms of the transformation of one kind of an organism into another different kind of an organism takes place too slowly to occur, and yet in the fossil record the evolutionists tell us it took place to rapidly to be caught. Now, this puts the evolutionists in an interesting position in believing in something that they've not seen. And I find that no different than what they claim, for example, against the creationists.

MARGARET WARNER: All right. So Barbara Schulz, it goes back to that question: Is evolution--what can you say to demonstrate that evolution is more proven or more scientific than creationism if--do you accept that evolution also has some unknown elements and some unprovable elements?

BARBARA SCHULZ: Certainly, it's a very complex idea, and certainly various components of the idea of evolution are being debated among scientists today. There are many debates raging in many different areas. But those debates don't negate the fact that we have evidence for change in populations through time, and that's what we're saying that evolution is explaining. It's explaining the changes that occur in populations. It's explaining that there is variation in populations and not all of those variations survive from one generation to the next. So we're looking at the way that the genes that are carried with an individual in a population either get lost or get passed on to the next generation. The idea of evolution then helps students explain and understand how adaptations can occur. Probably one of the biggest misconceptions on the part of students and perhaps the general public is that an individual organism can adapt to its environment when, in effect, this not the case at all, it's that gene pools, all of those genes within a population, living at a specific time, change from one time period to the next. They change gradually. They change based on influences of the environment and impacts of other organisms. Students need to understand that as a process.

MARGARET WARNER: All right. Let me get Mr. Witwer back in this. Mr. Witwer, do you think that a belief in evolution and a belief in a divine creator are necessarily exclusive? I mean, are they always going to be in conflict, or could they be reconciled?

MARK WITWER: I think it's important for students to understand that any kind of an explanation of ultimate origins, which this is about, of course, this is a little different than discussing about gravitation or the nature of the atom in that just by the nature of dealing with the origin of life and then the diversification of life over time, you're dealing with a different kind of issue, and it's just loaded deep with philosophical implications. I think students need to understand that much of what drives some of the evolutionary thinking, not all of it, and I don't mean to broad-brush evolutionists, but much of what drives some of this is naturalism, belief that nature is all there is, and so necessarily we must be able to find natural explanations for everything. We can and we must.

It's sort of assumed, where creationism--starting from a different starting point we'll look at the evidence and see where it takes us but we don't have to have a natural explanation for everything. And if the evidence seems to lead elsewhere, which I think it does in the case of large changes, then we don't have a problem saying it may be something science can't study. We're not talking about bringing religion into the classroom in the sense of saying now we'll tell you what did it, but it just automatically takes you to the point of saying this may be something science is not able to answer.

MARGARET WARNER: In other words, there may be things that are unknowable or not explainable?

MARK WITWER: There may be limits to what we can do. What do we do with the evidence, itself, for large changes now we're talking about. Much of our discussion has been about small changes which no one really debates. What do we do if the evidence is taking in one direction, and materialistic philosophy, naturalism, the belief in nature is all there is--is taking somewhere else. That's a rather uncomfortable position to be in if you're not able to at least say maybe there's something going on here that science isn't able to address.

MARGARET WARNER: Mr. Kennedy, what do you say to that?

DONALD KENNEDY: I think much of the creation/science argument, as it calls itself, is not nearly as thoughtful as what we just heard. I think it consists quite largely of arguments about what is missing from evolution, and I think no scientist would attempt to claim that we have the whole story, just that we have an extraordinarily robust theory accompanied by and derived from a whole range of observations and experiments that does explain organic diversity. As to the differences of opinion, we heard about Steven J. Gould. In fact, Steven J. Gould in this booklet disavows the interpretation that we've just heard.

MARGARET WARNER: From Mr. Spohn.

DONALD KENNEDY: Yes. He has some differences of view about tempo and mode in evolution. But he is by no means arguing with the structure of the fundamental hypothesis, as indeed most scientists are. The last point I want to make us to do with this alleged conflict between science and religion. Look, most scientists I know are spiritual and are serious about it, and most of the world's great religions accept evolution and have no problem with it. This is not a broad conflict between theological conviction and science; it's just not.

MARGARET WARNER: All right. I'm sorry. We'll have to leave it there. Thank you all four very much.