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Photo of Arden Bement

Dr. Arden L. Bement, Jr.
National Science Foundation

"The Criticality of Proof: Not Just Words, But Bones"
University of Pennsylvania
Museum of Archeology and Anthropology
Philadelphia, Pennsylvania

April 17, 2008

Good Evening and thank you for the opportunity to speak tonight--and thank you for the magnificence of this exhibit. I am indebted to Debra Wince Smith for her invitation.

I have titled my remarks, "The Criticality of Proof: Not Just Words, But Bones."

I must say that, speaking here, surrounded by these beautiful artifacts produced by people long dead, but probably indistinguishable from us in most respects, is awe inspiring. It reminds me of a highlight from the career of the great English archeologist and Egyptologist Howard Carter, the famous discoverer of the tomb of King Tut.

Carter's teams of diggers discovered the steps to the tomb in 1922.

However, he declined to fulfill his life's ambition -- to enter that storied tomb -- until his patron Lord Carnarvon arrived from England almost two weeks later.

On November 26, Carter made a hole in the door and leaned in, holding a candle, to take a look. Standing behind him Carnarvon asked, "Can you see anything?"

"Yes," Carter answered, "wonderful things."

And we know looking at the exhibit here at the University of Pennsylvania Museum of Archaeology and Anthropology that we can make the same exclamation -- wonderful things.

"Surviving: the Body of Evidence" is designed to shine a light of its own on one of the most important stories in the history of science. This is the story without which there would be no such discipline as science: the story of evolution of the human species.

As the director of the National Science Foundation, I am extremely proud of NSF's role as a supporter of "Surviving." As most of you know, this new, interactive exhibition, took three years to plan.

"Surviving" explores the very process of evolution and its profound impact on the human race.

Quite possibly there is no more important story to provide for the general public than this seminal tale. Scientists have pieced together, from a scrap of bone here, a DNA sample there, a fragment of skeleton elsewhere, the compelling story of humankind’s progression.

It traces the transition over geological time from primitive bands of anthropoids roaming the savannahs of Africa to a species that is able not only to travel into space and plumb the depths of the oceans, but also to harness increasingly complex and precise tools to pinpoint its own origins and development over millennia.

Telling that story has never been more important.

Especially in today's climate, in which the public is bombarded with contradictory and often inaccurate information about what evolution is -- and isn't. Even whether humans themselves have evolved, as science tells us unequivocally they have.

We have even seen the legal system called in to referee competing claims about what should -- or should not -- be taught in science classrooms about evolution as the organizing theme of modern biological science.

Claims are frequently and off-handedly made that evolution is "only a theory."

That argument itself is useful to some precisely because it plays on the general public's unfamiliarity with the jargon of science to unfairly question the value of the science itself.

To digress for a moment, how serious is the public's lack of knowledge about science and the scientific method?

Well, according to a survey released late last year, more than 1,300 Americans aged 18 or older were polled, with results indicating that many of these adults aren't particularly well informed about science.

Nevertheless, the same poll found that they do consider science critical and think that the current level of science education is inadequate for our times.

In fact, 44 percent of U.S. adults grade the quality of science education in this country at a "C" level or lower, and 79 percent say there isn't enough attention being given to it.

Based on these findings one should not be surprised by the controversy that surrounds the teaching of evolution. Human evolution, by its very nature, has long been steeped in controversy.

Fifty years ago, British anatomist Wilfrid Le Gros Clark explained in a lecture why evolutionary scientists argue so vehemently about how ancient precursors eventually gave way to modern humans.

"Every fossil relic which appears to throw light on connecting links in man's ancestry always has, and always will, arouse controversy," he said, "and it is right that this should be so, for it is very true that the sparks of controversy often illuminate the way to truth."

So, yes, there is controversy as to detail. And so there should be.

But what is often lost in the public debate about evolution generally, and human evolution in particular, is that while scientists can and do debate the details, none seriously debate that such a process took place.

So, let's come back to that question about "theory" and its place in the study of human origins. And in doing so, let us draw from recent documents produced by the National Academy of Sciences and the Institute of Medicine.

In many public discussions of science in general, and evolution in particular, there are serious misconceptions about the meaning of the word "theory."

When we use theory in conversation it comes closest in definition to what we mean as speculation. We say, for example: "my theory of why he did not arrive on time is that he got lost and was too embarrassed to admit it." That's your speculation.

You could be right or wrong. It's just your hunch; it's what you believe and there often is no particular evidence offered to support your claim. Usually none is expected.

When scientists use the word "theory" its meaning is almost the exact opposite to its use in ordinary conversation.

Something in science becomes a "theory" when the evidence for it is so compelling that there is every likelihood that it will persist, for example, the theory of gravity, atomic theory, or germ theory.

This does not mean that science is inflexible, only that for scientific theories to change and adapt—to evolve, if you will—the evidence compelling the change must itself be compelling.

The conduct of science has strict guidelines and limitations.

To be considered in the realm of science, something must be observable -- either with the naked eye or a microscope, instrument, telescope, satellite, sensor network or any other tool that can capture an image, motion or property.

Scientists observe nature and come up with testable questions to make sure they can verify what they see. The two operative words here are observable and testable.

The testable component is especially rigorous because the results claimed and documented by the original scientist must be able to be replicated by other scientists using the same process. If these subsequent tests do not reveal similar results then the science must find new pathways to achieve truth.

For example, the evidence for evolution has been substantiated and grown consistently for over 150 years. Its evidence is found in everything from fossil records to DNA, as one can easily learn from touring the exhibit.

A powerful concept, belief or idea can be revolutionary but it is not science if it is not observable and testable. An idea gains its credibility by others being convinced of its value or appeal. That makes ideas and beliefs more pervasive and more flexible than science, which is strictly confined by proof.

And it is the twin issues of testability and observability that place evolutionary theory squarely in the realm of science and the concept of "creationism," solidly into the realm of belief.

The difference, it would seem is a fairly straightforward one.

However, our decentralized system of formal education, which by practice aligns to local and regional norms, may not make that vital, even fundamental, difference clear.

Which is why exhibits like "Surviving: The Body of Evidence" are so very, very important to our efforts as a nation to raise the level of science literacy.

By that I do not mean that every child will grow up to be a scientist, but that every citizen will comprehend how science works and understand both is strengths and its weaknesses.

For visitors, the exhibit provides the opportunity to engage in a variety of multimedia programs and to see and touch more than 100 casts of fossil bones from the primate and human evolutionary records.

This is a rich exploration of physical anthropology and its relationship to evolutionary science.

Interactive activities throughout the exhibition enhance an examination of the human body in the context of its evolutionary strengths and limitations. Large-screen technologies help bring complex topics to life at an accessible level.

"'Surviving,'" in the words of Richard Hodges, the Williams Director of the Penn Museum, "is an exciting new way for the public to learn about themselves from an evolutionary perspective -- and discover why learning about evolution matters."

In doing so, "Surviving" and other, similar NSF-supported educational endeavors, such as IMAX films, television programs and other media are attempting to present key scientific concepts in accessible and memorable formats.

In this day and age, it is critical to expose general audiences to science in a meaningful way that they may never have experienced in school.

It isn't possible to single out any of the six sections of the exhibit as the most important to a full understanding of humanity in the evolutionary context.

But I think it is important that the sixth and final section focuses on the concept that "We Keep Evolving," inviting, as it does, the visitor to assess the impact of evolution both today and into the future.

Visitors can consider imagined futures as shared by comparative geneticists, evolutionary biologists, anthropologists, and even local school children, through video presentations.

Finally, as they leave the exhibition, the visitors will have the opportunity to take part in a poll of ideas about where we are going from here, in evolutionary terms.

These ideas add to the exhibition itself, its own process of evolution, and engages the visitor in the act of envisioning our shared future.

This engaging strategy, I believe, illuminates the process of evolution for exactly what it is: dynamic and ongoing. Not something that happened in the past and is no longer relevant.

In my opening remarks, I noted that the people of ancient Egypt, who created the wonderful artifacts that surround us here, would have been practically indistinguishable from ourselves.

In many ways, I believe that is true. They obviously, for example, were very accomplished engineers, as the existence of the Great Pyramids reminds us today.

But there is one very important difference between them and us.

A different branch of science from evolutionary biology -- namely archeology -- has taught us that these otherwise very sophisticated people looked to the mystical, not the scientific method, to explain their origins.

As "Surviving," shows us, more than a century of observable and testable science has illuminated for us quite a different path. The study of evolution and human evolution in particular, has shown us "wonderful things."

We should not turn our backs on that hard-earned knowledge.