[Paleopsych] Jerry Coyne: The Case against Intelligent Design

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Jerry Coyne: The Case against Intelligent Design
The Faith That Dare Not Speak Its Name
http://www.tnr.com/user/nregi.mhtml?i=20050822&s=coyne082205
Post date: 08.11.05
Issue date: 08.22.05

[Responses to this from the intelligent designers are most welcome!]

Of Pandas and People
By Percival Davis and Dean H. Kenyon
(Haughton Publishing Company, 170 pp., $24.95)

I.

Exactly eighty years after the Scopes "monkey trial" in Dayton, Tennessee, 
history is about to repeat itself. In a courtroom in Harrisburg, Pennsylvania 
in late September, scientists and creationists will square off about whether 
and how high school students in Dover, Pennsylvania will learn about biological 
evolution. One would have assumed that these battles were over, but that is to 
underestimate the fury (and the ingenuity) of creationists scorned.

The Scopes trial of our day--Kitzmiller, et al v. Dover Area School
District et al--began innocuously. In the spring of 2004, the
district's textbook review committee recommended that a new
commercial text replace the outdated biology book. At a school board
meeting in June, William Buckingham, the chair of the board's
curriculum committee, complained that the proposed replacement book
was "laced with Darwinism." After challenging the audience to trace
its roots back to a monkey, he suggested that a more suitable
textbook would include biblical theories of creation. When asked
whether this might offend those of other faiths, Buckingham replied,
"This country wasn't founded on Muslim beliefs or evolution. This
country was founded on Christianity and our students should be taught
as such." Defending his views a week later, Buckingham reportedly
pleaded: "Two thousand years ago, someone died on a cross. Can't
someone take a stand for him?" And he added: "Nowhere in the
Constitution does it call for a separation of church and state."

After a summer of heated but inconclusive wrangling, on October 18,
2004 the Dover school board passed, by a vote of six to three, a
resolution that read: "Students will be made aware of gaps/problems
in Darwin's theory and of other theories of evolution including, but
not limited to, intelligent design. Note: Origins of Life is not
taught." A month later, the Dover school district issued a press
release revealing how the alternative of "intelligent design" was to
be presented. Before starting to teach evolution, biology teachers
were to read their ninth-grade students a statement, which included
the following language:

The Pennsylvania Academic Standards require students to learn about
Darwin's Theory of Evolution and eventually to take a standardized
test of which evolution is a part.

Because Darwin's Theory is a theory, it continues to be tested as new
evidence is discovered. The Theory is not a fact. Gaps in the Theory
exist for which there is no evidence.... Intelligent design is an
explanation of the origin of life that differs from Darwin's view.
The reference book, Of Pandas and People, is available for students
to see if they would like to explore this view in an effort to gain
an understanding of what intelligent design actually involves. As is
true with any theory, students are encouraged to keep an open mind.


The results were dramatic but predictable. Two school board members
resigned. All eight science teachers at Dover High School sent a
letter to the school superintendent pointing out that "intelligent
design is not science. It is not biology. It is not an accepted
scientific theory." The biology teachers asked to be excused from
reading the statement, claiming that to do so would "knowingly and
intentionally misrepresent subject matter or curriculum," a violation
of their code of professional standards. And so, in January of this
year, all ninth-grade biology classes were visited by the assistant
superintendent himself, who read the mandated disclaimer while the
teachers and a few students left the room.

Inevitably, the controversy went to the courts. Eleven Dover parents
filed suit against the school district and its board of directors,
asking that the "intelligent design" policy be rescinded for
fostering "excessive entanglement of government and religion, coerced
religious instruction, and an endorsement by the state of religion
over non-religion and of one religious viewpoint over others." The
plaintiffs are represented by the Philadelphia law firm of Pepper
Hamilton, the Pennsylvania American Civil Liberties Union, and
Americans United for Separation of Church and State; the defendants,
by the Thomas More Law Center, a conservative Christian organization
in Ann Arbor, Michigan.

Why all the fuss about a seemingly inoffensive statement? Who could
possibly object to students "keep[ing] an open mind" and examining a
respectable-sounding alternative to evolution? Isn't science about
testing theories against each other? The furor makes sense only in
light of the tortuous history of creationism in America. Since it
arose after World War I, Christianfundamentalist creationism has
undergone its own evolution, taking on newer forms after absorbing
repeated blows from the courts. "Intelligent design," as I will show,
is merely the latest incarnation of the biblical creationism espoused
by William Jennings Bryan in Dayton. Far from a respectable
scientific alternative to evolution, it is a clever attempt to sneak
religion, cloaked in the guise of science, into the public schools.

The journey from Dayton to Dover was marked by a series of legal
verdicts, only one of which, the Scopes trial, favored creationism.
In 1925, John Scopes, a high school teacher, was convicted of
violating Tennessee's Butler Act, which prohibited the teaching of
"any theory that denies the Story of Divine Creation of Man as taught
in the Bible, and to teach instead that man has descended from a
lower order of animal." The verdict was reversed on a technicality
(the judge, instead of the jury, levied the $100 fine), so the case
was never appealed. In the wake of Scopes, anti-evolution laws were
passed in Mississippi and Arkansas, adding to those passed by Florida
and Oklahoma in 1923. Although these laws were rarely enforced,
evolution nonetheless quickly disappeared from most high school
biology textbooks because publishers feared losing sales in the
South, where anti-evolution sentiment ran high.

In 1957, the situation changed. With the launch of Sputnik, Americans
awoke to find that a scientifically advanced Soviet Union had beaten
the United States into space. This spurred rapid revisions of science
textbooks, some emphasizing biological evolution. But the anti-
evolution statutes were still in force, and so some teachers using
newer books were violating the law. One of these teachers, Susan
Epperson, brought suit against the state of Arkansas for violating
the Establishment Clause. She won the right to teach evolution, and
Epperson v. Arkansas was upheld by the United States Supreme Court in
1968, only a year after Tennessee finally rescinded the Butler Act.
Finally it was legal to teach evolution everywhere in America.

The opponents of evolution proceeded to re-think their strategy,
deciding that if they could not beat scientists, they would join
them. They thus recast themselves as "scientific creationists,"
proposing an ostensibly non-religious alternative to the theory of
evolution that might be acceptable in the classroom. But the
empirical claims of scientific creationism--that the Earth is young
(6,000 to 10,000 years old), that all species were created suddenly
and simultaneously, that mass extinctions were caused by a great
worldwide flood--bore a suspicious resemblance to creation stories in
the Bible. This strategy was devised largely by Henry Morris, an
engineering professor who headed the influential Institute for
Creation Research in San Diego and helped to write the textbook
Scientific Creationism. The book came in two versions: one purged of
religious references for the public schools, the other containing a
scriptural appendix explaining that the science came from
interpreting the Bible literally.

Scientific creationism proved a bust for two reasons. First, the
"science" was ludicrously wrong. We have known for a long time that
the Earth is 4.6 billion years old (the 6,000- to 10,000-year claim
comes from biblical statements, including toting up the number of
"begats") and that species were not created suddenly or
simultaneously (not only do most species go extinct, but various
groups appear at different times in the fossil record), and we have
ample evidence for species' changing over time, as well as for
fossils that illustrate large morphological transformations. Most
risible was Scientific Creationism's struggle to explain the
geological record as a result of a great flood: according to its
account, "primitive" organisms such as fish would be found in the
lowest layers, while mammals and more "advanced" species appeared in
higher layers because they climbed hills and mountains to escape the
rising waters. Why dolphins are found in the upper strata with other
mammals is one of many facts that this ludicrous fantasy fails to
explain.

Scientific creationism also came to grief because its advocates did
not adequately hide its religious underpinnings. In 1981, the
Arkansas legislature passed an "equal time" bill mandating balanced
treatment for "evolution science" and "creation science" in the
classroom. The bill was quickly challenged in federal court by a
group of religious and scientific plaintiffs led by a Methodist
minister named William McLean. The defense was easily outgunned, with
Judge William Overton quickly spotting biblical literalism underlying
the scientific-creationist arguments. In a landmark opinion (and a
masterpiece of legal argument), Overton ruled in McLean v. Arkansas
Board of Education that the balanced-treatment act was
unconstitutional, asserting that it violated the Establishment Clause
in three ways: it lacked a secular legislative purpose, its primary
effect was to advance religion, and it fostered excessive government
entanglement with religion.

McLean v. Arkansas Board of Education began a string of legal
setbacks for scientific creationists. Five years later, in Edwards v.
Aguillard, the Supreme Court held that Louisiana's "Creationism Act"--
an act that required the teaching of evolution in public schools to
be balanced by instruction in "creation science"--was
unconstitutional. In the last two decades, federal courts have also
used the First Amendment to allow schools to prohibit teaching
creationism and to ban school districts from requiring teachers to
read evolution disclaimers similar to the one used in Dover,
Pennsylvania. To get around these rulings, schools in Alabama,
Arkansas, and Georgia began pasting warning stickers in biology
textbooks, as if learning about evolution could endanger one's mental
health. A recent specimen from Cobb County, Georgia reads: "This
textbook contains material on evolution. Evolution is a theory, not a
fact, regarding the origin of living things. This material should be
approached with an open mind, studied carefully and critically
considered."

To laypeople--particularly those unfamiliar with the scientific
status of evolution, which is actually a theory and a fact--the
phrasing may seem harmless. But in 2005 a federal judge ordered the
stickers removed. By singling out evolution as uniquely controversial
among scientific theories, the stickers catered to religious biases
and thus violated the First Amendment.

But the creationists did not despair. They are animated, after all,
by faith. And they are very resourceful. They came up with
intelligent design.


II.

Intelligent design, or ID, is the latest pseudoscientific incarnation of 
religious creationism, cleverly crafted by a new group of enthusiasts to 
circumvent recent legal restrictions. ID comes in two parts. The first is a 
simple critique of evolutionary theory, to the effect that Darwinism, as an 
explanation of the origin, the development, and the diversity of life, is 
fatally flawed. The second is the assertion that the major features of life are 
best understood as the result of creation by a supernatural intelligent 
designer. To understand ID, then, we must first understand modern evolutionary 
theory (often called "neo-Darwinism" to take into account post- Darwinian 
modifications).

It is important to realize at the outset that evolution is not "just a theory." 
It is, again, a theory and a fact. Although non-scientists often equate 
"theory" with "hunch" or "wild guess," the Oxford English Dictionary defines a 
scientific theory as "a scheme or system of ideas or statements held as an 
explanation or account of a group of facts or phenomena; a hypothesis that has 
been confirmed or established by observation or experiment, and is propounded 
or accepted as accounting for the known facts." In science, a theory is a 
convincing explanation for a diversity of data from nature. Thus scientists 
speak of "atomic theory" and "gravitational theory" as explanations for the 
properties of matter and the mutual attraction of physical bodies. It makes as 
little sense to doubt the factuality of evolution as to doubt the factuality of 
gravity.

Neo-Darwinian theory is not one proposition but several. The first proposition 
is that populations of organisms have evolved. (Darwin, who used the word 
"evolved" only once in On the Origin of Species, called this principle "descent 
with modification.") That is, the species on earth today are the descendants of 
other species that lived earlier, and the change in these lineages has been 
gradual, taking thousands to millions of years. Humans, for example, evolved 
from distinctly different organisms that had smaller brains and probably lived 
in trees.

The second proposition is that new forms of life are continually
generated by the splitting of a single lineage into two or more
lineages. This is known as "speciation." About five million years
ago, a species of primates split into two distinct lineages: one
leading to modern chimpanzees and the other to modern humans. And
this ancestral primate itself shared a common ancestor with earlier
primates, which in turn shared a common ancestor with other mammals.
The earlier ancestor of all mammals shared an even earlier ancestor
with reptiles, and so on back to the origin of life. Such successive
splitting yields the common metaphor of an evolutionary "tree of
life," whose root was the first species to arise and whose twigs are
the millions of living species. Any two extant species share a common
ancestor, which can in principle be found by tracing that pair of
twigs back through the branches to the node where they meet.
(Extinction, of course, has pruned some branches--pterodactyls, for
example--which represent groups that died off without descendants.)
We are more closely related to chimpanzees than to orangutans because
our common ancestor with these primates lived five million versus ten
million years ago, respectively. (It is important to note that
although we share a common ancestor with apes, we did not evolve from
living apes, but from apelike species that no longer exist.
Similarly, I am related to my cousin, but the ancestors we share are
two extinct grandparents.)

The third proposition is that most (though not all) of evolutionary
change is probably driven by natural selection: individuals carrying
genes that better suit them to the current environment leave more
offspring than individuals carrying genes that make them less
adapted. Over time, the genetic composition of a population changes,
improving its "fit" to the environment. This increasing fit is what
gives organisms the appearance of design, although, as we shall see,
the "design" can be flawed.

These three propositions were first articulated in 1859 by Darwin in
On the Origin of Species, and they have not changed substantially,
although they have been refined and supplemented by modern work. But
Darwin did not propose these ideas as pure "theory"; he also provided
voluminous and convincing evidence for them. The weight of this
evidence was so overwhelming that it crushed creationism. Within
fifteen years, nearly all biologists, previously adherents of
"natural theology," abandoned that view and accepted Darwin's first
two propositions. Broad acceptance of natural selection came much
later, around 1930.

The overwhelming evidence for evolution can be found in many books
(and on many websites). Here I wish to present just a few
observations that not only support the neo-Darwinist account, but in
so doing refute the alternative theory of creationism--that God
specially created organisms and their attributes. Given the
similarity between the claims of intelligent design and creationism,
it is not surprising that these observations also refute the major
tenets of ID.

The fossil record is the most obvious place to search for evidence of
evolution. Although the record was sparse in Darwin's time, there
were already findings that suggested evolution. The living armadillos
of South America bore a striking resemblance to fossil glyptodonts,
extinct armored mammals whose fossils occurred in the same area. This
suggested that glyptodonts and armadillos shared a common South
American ancestry. And the record clearly displayed changes in the
forms of life existing over large spans of time, with the deepest and
oldest sediments showing marine invertebrates, with fishes appearing
much later, and still later amphibians, reptiles, and mammals (along
with the persistence of some groups found in earlier stages). This
sequence of change was in fact established by creationist geologists
long before Darwin, and was often thought to reflect hundreds of acts
of divine creation. (This does not exactly comport with the account
given in Genesis.)

Yet evolution predicts not just successions of forms, but also
genetic lineages from ancestors to descendants. The absence of such
transitional series in the fossil record bothered Darwin, who called
this "the most obvious and serious objection that can be urged
against the theory." (He attributed the missing links, quite
reasonably, to the imperfection of the fossil record and the dearth
of paleontological collections.) But this objection is no longer
valid. Since 1859, paleontologists have turned up Darwin's missing
evidence: fossils in profusion, with many sequences showing
evolutionary change. In large and small organisms, we can trace,
through successive layers of the fossil record, evolutionary changes
occurring in lineages. Diatoms get bigger, clamshells get ribbier,
horses get larger and toothier, and the human lineage evolves bigger
brains, smaller teeth, and increased efficiency at bipedal walking.
Moreover, we now have transitional forms connecting major groups of
organisms, including fish with tetrapods, dinosaurs with birds,
reptiles with mammals, and land mammals with whales. Darwin predicted
that such forms would be found, and their discovery vindicated him
fully. It also destroys the creationist notion that species were
created in their present form and thereafter remained unchanged.

Darwin's second line of evidence comprised the developmental and
structural remnants of past ancestry that we find in living species--
those features that Stephen Jay Gould called "the senseless signs of
history." Examples are numerous. Both birds and toothless anteaters
develop tooth buds as embryos, but the teeth are aborted and never
erupt; the buds are the remnants of the teeth of the reptilian
ancestor of birds and the toothed ancestor of anteaters. The
flightless kiwi bird of New Zealand, familiar from shoe-polish cans,
has tiny vestigial wings hidden under its feathers; they are
completely useless, but they attest to the fact that kiwis, like all
flightless birds, evolved from flying ancestors. Some cave animals,
descended from sighted ancestors that invaded caves, have rudimentary
eyes that cannot see; the eyes degenerated after they were no longer
needed. A creator, especially an intelligent one, would not bestow
useless tooth buds, wings, or eyes on large numbers of species.

The human body is also a palimpsest of our ancestry. Our appendix is
the vestigial remnant of an intestinal pouch used to ferment the hard-
to-digest plant diets of our ancestors. (Orangutans and grazing
animals have a large hollow appendix instead of the tiny, wormlike
one that we possess.) An appendix is simply a bad thing to have. It
is certainly not the product of intelligent design: how many humans
died of appendicitis before surgery was invented? And consider also
lanugo. Five months after conception, human fetuses grow a thin coat
of hair, called lanugo, all over their bodies. It does not seem
useful--after all, it is a comfortable 98.6 degrees in utero--and the
hair is usually shed shortly before birth. The feature makes sense
only as an evolutionary remnant of our primate ancestry; fetal apes
also grow such a coat, but they do not shed it.

Recent studies of the human genome provide more evidence that we were
not created ex nihilo. Our genome is a veritable Gemisch of non-
functional DNA, including many inactive "pseudogenes" that were
functional in our ancestors. Why do humans, unlike most mammals,
require vitamin C in our diet? Because primates cannot synthesize
this essential nutrient from simpler chemicals. Yet we still carry
all the genes for synthesizing vitamin C. The gene used for the last
step in this pathway was inactivated by mutations forty million years
ago, probably because it was unnecessary in fruit-eating primates.
But it still sits in our DNA, one of many useless remnants testifying
to our evolutionary ancestry.

Darwin's third line of evidence came from biogeography, the study of
the geographic distribution of plants and animals. I have already
mentioned what Darwin called his "Law of Succession": living
organisms in an area most closely resemble fossils found in the same
location. This implies that the former evolved from the latter. But
Darwin found his strongest evidence on "oceanic islands"--those
islands, such as Hawaii and the Galápagos, that were never connected
to continents but arose, bereft of life, from beneath the sea.

What struck Darwin about oceanic islands--as opposed to continents or
"continental islands" such as Great Britain, which were once
connected to continents--was the bizarre nature of their flora and
fauna. Oceanic islands are simply missing or impoverished in many
types of animals. Hawaii has no native mammals, reptiles, or
amphibians. These animals, as well as freshwater fish, are also
missing on St. Helena, a remote oceanic island in the middle of the
South Atlantic Ocean. It seems that the intelligent designer forgot
to stock oceanic (but not continental!) islands with a sufficient
variety of animals. One might respond that this was a strategy of the
creator, as those organisms might not survive on islands. But this
objection fails, because such animals often do spectacularly well
when introduced by humans. Hawaii has been overrun by the introduced
cane toad and mongoose, to the detriment of its native fauna.

Strikingly, the native groups that are present on these islands--
mainly plants, insects, and birds--are present in profusion,
consisting of clusters of numerous similar species. The Galápagos
archipelago harbors twenty-three species of land birds, of which
fourteen species are finches. Nowhere else in the world will you find
an area in which two-thirds of the birds are finches. Hawaii has
similar "radiations" of fruit flies and silversword plants, while St.
Helena is overloaded with ferns and weevils. Compared with continents
or continental islands, then, oceanic islands have unbalanced flora
and fauna, lacking many familiar groups but having an over-
representation of some species.

Moreover, the animals and the plants inhabiting oceanic islands bear
the greatest similarity to species found on the nearest mainland. As
Darwin noted when describing the species of the Galápagos, this
similarity occurs despite a great difference in habitat, a fact
militating against creationism:

Why should the species which are supposed to have been created in the
Galápagos Archipelago, and nowhere else, bear so plainly the stamp of
affinity to those created in America? There is nothing in the
conditions of life, in the geological nature of the islands, in their
height or climate, or in the proportions in which the several classes
are associated together, which resembles closely the conditions of
the South American coast: in fact there is a considerable
dissimilarity in all these respects.

As the final peg in Darwin's biogeographic argument, he noted that
the kinds of organisms commonly found on oceanic islands--birds,
plants, and insects--are those that can easily get there. Insects and
birds can fly to islands (or be blown there by winds), and the seeds
of plants can be transported by winds or ocean currents, or in the
stomachs of birds. Hawaii may have no native terrestrial mammals, but
the islands do harbor one native aquatic mammal, the monk seal, and
one native flying mammal, the hoary bat. In a direct challenge to
creationists (and now also to advocates of ID), Darwin posed this
rhetorical question:

Though terrestrial mammals do not occur on oceanic islands, aerial
mammals do occur on almost every island. New Zealand possesses two
bats found nowhere else in the world: Norfolk Island, the Viti
Archipelago, the Bonin Islands, the Caroline and Marianne
Archipelagoes, and Mauritius, all possess their peculiar bats. Why,
it may be asked, has the supposed creative force produced bats and no
other mammals on remote islands?

The answer is that the creative force did not produce bats, or any
other creatures, on oceanic islands. All of Darwin's observations
about island biogeography point to one explanation: species on
islands descend from individuals who successfully colonized from the
mainland and subsequently evolved into new species. Only the theory
of evolution explains the paucity of mammals, birds, reptiles,
amphibians, and freshwater fish on oceanic islands (they cannot get
there), the radiation of some groups into many species (the few
species that make it to islands find empty niches and speciate
profusely), and the resemblance of island species to those from the
nearest mainland (an island colonist is most likely to have come from
the closest source).

On the last 150 years, immense amounts of new evidence have been
collected about biogeography, embryology, and, especially, the fossil
record. All of it supports evolution. But support for the idea of
natural selection was not so strong, and Darwin had no direct
evidence for it. He relied instead on two arguments. The first was
logical. If individuals in a population varied genetically (which
they do), and some of this variation affected the individual's chance
of leaving descendants (which seems likely), then natural selection
would work automatically, enriching the population in genes that
better adapted individuals to their environment.

The second argument was analogical. Artificial selection used by
breeders had wrought immense changes in plants and animals, a fact
familiar to everyone. From the ancestral wolf, humans selected forms
as diverse as Chihuahuas, St. Bernards, poodles, and bulldogs.
Starting with wild cabbage, breeders produced domestic cabbage,
broccoli, kohlrabi, kale, cauliflower, and Brussels sprouts.
Artificial selection is nearly identical to natural selection, except
that humans rather than the environment determine which variants
leave offspring. And if artificial selection can produce such a
diversity of domesticated plants and animals in a thousand-odd years,
natural selection could obviously do much more over millions of years.

But we no longer need to buttress natural selection solely with
analogy and logic. Biologists have now observed hundreds of cases of
natural selection, beginning with the well-known examples of
bacterial resistance to antibiotics, insect resistance to DDT, and
HIV resistance to antiviral drugs. Natural selection accounts for the
resistance of fish and mice to predators by making them more
camouflaged, and for the adaptation of plants to toxic minerals in
the soil. (A long list of examples may be found in Natural Selection
in the Wild, by John Endler.) Moreover, the strength of selection
observed in the wild, when extrapolated over long periods, is more
than adequate to explain the diversification of life on Earth.

Since 1859, Darwin's theories have been expanded, and we now know
that some evolutionary change can be caused by forces other than
natural selection. For example, random and non-adaptive changes in
the frequencies of different genetic variants--the genetic equivalent
of coin-tossing--have produced evolutionary changes in DNA sequences.
Yet selection is still the only known evolutionary force that can
produce the fit between organism and environment (or between organism
and organism) that makes nature seem "designed." As the geneticist
Theodosius Dobzhansky remarked, "Nothing in biology makes sense
except in the light of evolution."

And so evolution has graduated from theory to fact. We know that
species on earth today descended from earlier, different species, and
that every pair of species had a common ancestor that existed in the
past. Most evolutionary change in the features of organisms,
moreover, is almost certainly the result of natural selection. But we
must also remember that, like all scientific truths, the truth of
evolution is provisional: it could conceivably be overturned by
future investigations. It is possible (but unlikely!) that we could
find human fossils co-existing with dinosaurs, or fossils of birds
living alongside those of the earliest invertebrates 600 million
years ago. Either observation would sink neo-Darwinism for good.

When applied to evolution, the erroneous distinction between theory
and fact shows why tactics such as the Dover disclaimer and the Cobb
County textbook sticker are doubly pernicious. To teach that a
scientific theory is equivalent to a "guess" or a "hunch" is deeply
misleading, and to assert that "evolution is a theory, not a fact" is
simply false. And why should evolution, alone among scientific
theories, be singled out with the caveat "This material should be
approached with an open mind, studied carefully and critically
considered"? Why haven't school boards put similar warnings in
physics textbooks, noting that gravity and electrons are only
theories, not facts, and should be critically considered? After all,
nobody has ever seen gravity or an electron. The reason that
evolution stands alone is clear: other scientific theories do not
offend religious sensibilities.

III.

Given the copious evidence for evolution, it seems unlikely that it
will be replaced by an alternative theory. But that is exactly what
intelligent-design creationists are demanding. Is there some dramatic
new evidence, then, or some insufficiency of neo-Darwinism, that
warrants overturning the theory of evolution?

The question is worth asking, but the answer is no. Intelligent
design is simply the third attempt of creationists to proselytize our
children at the expense of good science and clear thinking. Having
failed to ban evolution from schools, and later to get equal
classroom time for scientific creationism, they have made a few
adjustments designed to sneak Christian cosmogony past the First
Amendment. And these adjustments have given ID a popularity never
enjoyed by earlier forms of creationism. Even the president of the
United States has lent a sympathetic ear: George W. Bush recently
told reporters in Texas that intelligent design should be taught in
public schools alongside evolution because "part of education is to
expose people to different schools of thought." Articles by IDers, or
about their "theory," regularly appear in mainstream publications
such as The New York Times.

Why have the new image and the new approach been more successful? For
a start, IDers have duped many people by further removing God from
the picture, or at least hiding him behind the frame. No longer do
creationists mention a deity, or even a creator, but simply a neutral-
sounding "intelligent designer," as if it were not the same thing.
This designer could in principle be Brahma, or the Taoist P'an Ku, or
even a space alien; but ID creationists, as will be evident to
anybody who attends to all that they say, mean only one entity: the
biblical God. Their problem is that invoking this deity in science
classes in public schools is unconstitutional. So IDers never refer
openly to God, and people unfamiliar with the history of their
creationist doctrine might believe that there is a real scientific
theory afoot. They use imposing new terms such as "irreducible
complexity," which make their arguments seem more sophisticated than
those of earlier creationists.

In addition, many IDers have more impressive academic credentials
than did earlier scientific creationists, whose talks and antics
always bore a whiff of the revival meeting. Unlike scientific
creationists, many IDers work at secular institutions rather than at
Bible schools. IDers work, speak, and write like trained academics;
they do not come off as barely repressed evangelists. Their ranks
include Phillip Johnson, the most prominent spokesperson for ID, and
a retired professor of law at the University of California, Berkeley;
Michael Behe, a professor of biochemistry at Lehigh University;
William Dembski, a mathematician-philosopher and the director of the
Center for Theology and Science at Southern Baptist Theological
Seminary; and Jonathan Wells, who has a doctorate in biology from
Berkeley.

All of these proponents, save Johnson, are senior fellows at the
Center for Science and Culture (CSC), a division of the Discovery
Institute, which is a conservative think tank in Seattle. (Johnson is
the "program advisor" to the CSC.) The CSC is the nerve center of the
intelligentdesign movement. Its origins are demonstrably religious:
as described by the Discovery Institute, the CSC was designed
explicitly "to defeat scientific materialism and its destructive
moral, cultural, and political legacies" and "to replace
materialistic explanations with the theistic understanding that
nature and human beings are created by God." Between them, these
IDers have published more than a dozen books about intelligent design
(Johnson alone has produced eight), which in turn have provoked
numerous responses by scientists. Let us examine one of their most
influential volumes, the textbook called Of Pandas and People. This
is the book recommended by the Dover school district as a "reference
book" for students interested in learning about intelligent design.

If Pandas and People is a textbook designed as an antidote to the
evolution segment of high school biology classes. It was first
published in 1989. By repackaging and updating a subset of
traditional young-earth creationist arguments while avoiding taking a
stand on any issues that might divide creationists (such as the age
of the Earth), it marked the beginning of the modern
intelligentdesign movement. By presenting the case for ID, it is
supposedly designed to give students a "balanced perspective" on
evolution. Although the second edition of Pandas is now twelve years
old (a third edition, called Design of Life, is in the works), it
accurately presents to students the major arguments for ID.

Pandas carefully avoids mentioning God (except under aliases such as
"intelligent designer," "master intellect," and so on); but a little
digging reveals the book's deep religious roots. One of its authors,
Percival Davis, wrote explicitly about his religious beliefs in his
book A Case for Creation, co-authored with Wayne Frair: "Truth as God
sees it is revealed in the pages of Scripture, and that revelation is
therefore more certainly true than any human rationalism. For the
creationist, revealed truth controls his view of the universe to at
least as great a degree as anything that has been advanced using the
scientific method." Its other author, Dean Kenyon, has written
approvingly of scientific creationism.

Pandas is published by the Haughton Publishing Company of Dallas, a
publisher of agricultural books, but the copyright is held by the
Foundation for Thought and Ethics (FTE) in Richardson, Texas.
Although the FTE website scrupulously avoids mentioning religion, its
articles of incorporation note with stark clarity that its "primary
purpose is both religious and educational, which includes, but is not
limited to, proclaiming, preaching, teaching, promoting,
broadcasting, disseminating, and otherwise making known the Christian
gospel and understanding of the Bible and the light it sheds on the
academic and social issues of our day." In a fund-raising letter for
the proposed third edition of Pandas, Jon Buell, president of the
FTE, is equally frank about his goals:

We will energetically continue to publish and propel these strategic
tools in the battle for the minds and hearts of the young.... Yes,
most young Americans are exposed to numerous gospel presentations.
But the fog of the alien world view deadens their responses. This is
why we have to inundate them with a rational, defensible, wellargued
Judeo-Christian world view. FTE's carefully-researched books do just
that.

Charles Thaxton, the "academic editor" of Pandas, is the director of
curriculum research for FTE and a fellow of the CSC. In a proto-ID
book on the origin of life, Thaxton argued that "Special Creation by
a Creator beyond the cosmos is a plausible view of origin science."

Given Pandas' pedigree and the affiliations of its authors, it is not
surprising that the book is nothing more than disguised creationism.
What is surprising is the transparency of this disguise. Despite the
efforts of IDers to come up with new anti-Darwinian arguments, Pandas
turns out to be nothing more than recycled scientific creationism,
with most of the old arguments buffed up and proffered as new.
(Unlike scientific creationism, however, Pandas adopts a studied
neutrality toward the facts of astronomy and geology, instead of
denying them outright.)

Pandas' discussion of the Earth's age is a prime example of the book's
creationist roots, and of its anti-scientific attitude. If the Earth
were young--say, the 6,000 to 10,000 years old posited by "young
earth" biblical creationists--then evolution would be false. Life
simply could not have originated, evolved, and diversified in such a
short time. But we now know from several independent and mutually
corroborating lines of evidence that the Earth is 4.6 billion years
old. All geologists agree on this. So what is Pandas' stance on this
critical issue? The book merely notes that design proponents "are
divided on the issue of the earth's age. Some take the view that the
earth's history can be compressed into a framework of thousands of
years, while others adhere to the standard old earth chronology."
Well, what's the truth? This equivocation is an attempt to paper over
a strong disagreement between young-earth creationists and old-earth
creationists, both of whom have marched under the banner of ID. It is
typical of creationists to exploit disagreements between
evolutionists as proof that neo-Darwinism is dead while at the same
time hiding their own disagreements from the public.

This equivocation about the fundamental fact of Earth's age does not
bode well for the textbook's treatment of the fossil record. Indeed,
in this area the authors continue their misrepresentations. Their
basic premise is the old creationist argument that organisms appeared
simultaneously and have remained largely unchanged ever since. Pandas
says of the fossil record that "fully formed organisms appear all at
once, separated by distinct gaps." That's not exactly true. Different
types of organisms appear in a distinct sequence supporting
evolution. The first fossils of living organisms, bacteria, appear
3.5 billion years ago, followed two billion years later by algae, the
first organisms having true cells with a nucleus containing distinct
chromosomes. Then, 600 million years ago, we see the appearance of
rudimentary animals with shells, and many soft-bodied marine
organisms. Later, in the Cambrian period, about 543 million years
ago, a number of groups arose in a relatively short period of time,
the so-called "Cambrian explosion." ("Short period" here means
geologically short, in this case 10 million to 30 million years). The
Cambrian groups include mollusks, starfish, arthropods, worms, and
chordates (including vertebrates). And in some cases, such as worms,
modern groups do not just spring into being, but increase in
complexity over millions of years.

Creationists have always made much of the "Cambrian explosion," and
IDers are no exception. The relatively sudden appearance of many
groups seems to support the Genesis view of creation. But IDers--and
Pandas--fail to emphasize several facts. First, the Cambrian
explosion was not "sudden"; it took many millions of years. (We still
do not understand why many groups originated in even this relatively
short time, although it may reflect an artifact: the evolution of
easily fossilized hard parts suddenly made organisms capable of being
fossilized.) Moreover, the species of the Cambrian are no longer with
us, though their descendants are. But over time, nearly every species
that ever lived (more than 99 percent of them) has gone extinct
without leaving descendants. Finally, many animals and plants do not
show up as fossils until well after the Cambrian explosion: bony
fishes and land plants first appeared around 440 million years ago,
reptiles around 350 million years ago, mammals around 250 million
years ago, flowering plants around 210 million years ago, and human
ancestors around 5 million years ago. The staggered appearance of
groups that become very different over the next 500 million years
gives no support to the notion of instantaneously created species
that thereafter remain largely unchanged. If this record does reflect
the exertions of an intelligent designer, he was apparently
dissatisfied with nearly all of his creations, repeatedly destroying
them and creating a new set of species that just happened to resemble
descendants of those that he had destroyed.

Pandas also makes much of the supposed absence of transitional forms:
the "missing" links between major forms of life that, according to
evolutionary theory, must have existed as common ancestors. Their
absence, claim creationists, is a major embarrassment for
evolutionary biology. Phillip Johnson's influential book Darwin on
Trial, which appeared in 1993, particularly emphasizes these gaps,
which, IDers believe, reflect the designer's creation of major forms
ex nihilo. And there are indeed some animals, such as bats, that
appear in the fossil record suddenly, without obvious ancestors. Yet
in most cases these gaps are certainly due to the imperfection of the
fossil record. (Most organisms do not get buried in aquatic
sediments, which is a prerequisite for fossilization.) And species
that are soft-bodied or have fragile bones, such as bats, degrade
before they can fossilize. Paleontologists estimate that we have
fossils representing only about one in a thousand of all the species
that ever lived.

In its treatment of evolutionary transitions, Pandas is again guilty
of distortion. Paleontologists have uncovered many transitional forms
between major groups, almost more than we have a right to expect.
Pandas simply ignores--or waves away--these "non-missing links,"
stating that "we cannot form a smooth, unambiguous transitional
series linking, let's say, the first small horse to today's horse,
fishes to amphibians, or reptiles to mammals." This is flatly wrong.
All three cited transitions (and others) are well documented with
fossils. Moreover, the transitional forms appear at exactly the right
time in the fossil record: after the ancestral forms already existed,
but before the "linked" later group had evolved.

Take one example: the link between early reptiles and later mammals,
the so-called mammal-like reptiles. Three hundred fifty million years
ago, the world was full of reptiles, but there were no mammals. By
250 million years ago, mammals had appeared on the scene. (Fossil
reptiles are easily distinguished from fossil mammals by a complex of
skeletal traits including features of the teeth and skull.) Around
275 million years ago, forms appear that are intermediate in skeletal
traits between reptiles and mammals, in some cases so intermediate
that the animals cannot be unambiguously classified as either
reptiles or mammals. These mammal-like reptiles, which become less
reptilian and more mammalian with time, are the no-longer-missing
links between the two forms, important not only because they have the
traits of both forms, but also because they occur at exactly the
right time.

One of these traits is worth examining in detail because it is among
the finest examples of an evolutionary transition. This trait is the
"chewing" hinge where the jaw meets the skull. In early reptiles (and
their modern reptilian descendants), the lower jaw comprises several
bones, and the hinge is formed by the quadrate bone of the skull and
the articular bone of the jaw. As mammal-like reptiles become more
mammalian, these hinge bones become smaller, and ultimately the jaw
hinge shifts to a different pair of bones: the dentary (our
"jawbone") and the squamosal, another bone of the skull. (The
quadrate and articular, much reduced, moved into the middle ear of
mammals, forming two of the bones that transmit sounds from the
eardrum to the middle ear.) The dentary-squamosal articulation occurs
in all modern mammals, the quadrate-articular in modern reptiles; and
this difference is often used as the defining feature of these groups.

Like earlier creationist tracts, Pandas simply denies that this
evolution of the jaw hinge occurred. It asserts that "there is no
fossil record of such an amazing process," and further notes that
such a migration would be "extraordinary." This echoes the old
creationist argument that an adaptive transition from one type of
hinge to another by means of natural selection would be impossible:
members of a species could not eat during the evolutionary period
when their jaws were being unhinged and then rehinged. (The
implication is that the intelligent designer must have done this job
instantaneously and miraculously.) But we have long known how this
transition happened. It was easily accomplished by natural selection.
In 1958, fossil: the mammal-like reptile Diarthrognathus broomi. D.
broomi has, in fact, a double jaw joint with two hinges--the
reptilian one and the mammalian one! Obviously, this animal could
chew. What better "missing link" could we find?

It should embarrass IDers that so many of the missing links cited by
Pandas as evidence for supernatural intervention are no longer
missing. Creationists make a serious mistake when using the absence
of transitional forms as evidence for an intelligent designer. In the
last decade, paleontologists have uncovered a fairly complete
evolutionary series of whales, beginning with fully terrestrial
animals that became more and more aquatic over time, with their front
limbs evolving into flippers and their hind limbs and pelvis
gradually reduced to tiny vestiges. When such fossils are found, as
they often are, creationists must then punt and change their emphasis
to other missing links, continually retreating before the advance of
science.

As for other transitional forms, IDers simply dismiss them as
aberrant fossils. Pandas characterizes Homo erectus and other
probable human ancestors as "little more than apes." But this is
false. While H. erectus has a skull with large brow ridges and a
braincase much smaller than ours, the rest of its skeleton is nearly
identical to that of modern humans.The famous fossil Archaeopteryx, a
small dinosaur-like creature with teeth and a basically reptilian
skeleton but also with wings and feathers, is probably on or closely
related to the line of dinosaurs that evolved into birds. But Pandas
dismisses this fossil as just an "odd-ball" type, and laments instead
the lack of the unfossilizable: "If only we could find a fossil
showing scales developing the properties of feathers, or lungs that
were intermediate between the very different reptilian and avian
lungs, then we would have more to go on." It is again a typical
creationist strategy that when skeletons of missing links turn up,
creationists ignore them and insist that evidence of intermediacy be
sought instead in the soft parts that rarely fossilize. In sum, the
treatment of the fossil evidence for evolution in Pandas is shoddy
and deceptive, and offers no advance over the discredited arguments
of scientific creationism.

In contrast to its long treatment and dismissal of the fossil record,
Pandas barely deals with evidence for evolution from development and
vestigial traits. The best it can do is note that vestigial features
can have a function, and therefore are not really vestigial. The
vestigial pelvic bones and legs of the transitional whale
Basilosaurus, which were not connected to the skeleton, may have
functioned as a guide for the penis during mating. Such a use,
according to the authors of Pandas, means that the legs and pelvis
"were not vestigial as originally thought." But this argument is
wrong: no evolutionist denies that the remnants of ancestral traits
can retain some functionality or be co-opted for other uses. The
"penis guide" has every bone in the mammalian pelvis and rear leg in
reduced form--femur, tibia, fibula, and digits. In Basilosaurus,
nearly all of these structures lay within the body wall, and most
parts were immobile. Apparently the intelligent designer had a
whimsical streak, choosing to construct a sex aid that looked exactly
like a degenerate pelvis and set of hind limbs.

And what about the strong evidence for evolution from biogeography?
About this Pandas, like all creationist books, says nothing. The
omission is strategic. It would be very hard for IDers to give
plausible reasons why an "intelligent" designer stocked oceanic
islands with only a few types of animals and plants--and just those
types with the ability to disperse from the nearest mainland.
Biogeography has always been the Achilles' heel of creationists, so
they just ignore it.


IV.

Although intelligent design rejects much of the evidence for
evolution, it still admits that some evolutionary change occurs
through natural selection. This change is what Pandas calls
"microevolution," or "small scale genetic changes, observable in
organisms." Such microevolutionary changes include the evolution of
antibiotic resistance in bacteria, changes in the proportion of
different-colored moths due to predation by birds, and all changes
wrought by artificial selection. But Pandas hastens to add that
microevolution gives no evidence for the origin of diverse types of
organisms, because "these limited changes do not accumulate the way
Darwinian evolutionary theory requires in order to produce macro
changes. The process that produces macroevolutionary changes [defined
here as "large scale changes, leading to new levels of complexity"]
must be different from any that geneticists have studied so far."

So, though one can use selection to transform a wolf into either a
Chihuahua or a St. Bernard, that is merely microevolution: they are
all still dogs. And a DDT-resistant fly is still a fly. Pandas thus
echoes the ID assertion that natural selection cannot do more than
create microevolutionary changes: "It cannot produce new
characteristics. It only acts on traits that already exist." But this
is specious reasoning. As we have noted, fossils already show that
"macro change," as defined by Pandas, has occurred in the fossil
record (the evolution of fish into amphibians, and so on). And if
breeders have not turned a dog into another kind of animal, it is
because dog breeding has been going on for only a few thousand years,
while the differences between dogs and cats, for example, have
evolved over more than ten million years. No principle of evolution
dictates that evolutionary changes observed during a human lifetime
cannot be extrapolated to much longer periods.

In fact, Pandas admits that the fruit flies of Hawaii--a diverse
group of more than 300 species--have all evolved from a common
ancestor. We now know that this common ancestor lived about 20
million years ago. The species of Hawaiian flies differ in many
traits, including size, shape, ecology, color pattern, mating
behavior, and so on. One can in fact make a good case that some of
the fly species differ more from each other than humans differ from
chimps. Why, then, do IDers assert that chimps and humans (whose
ancestor lived only 5 million years ago) must have resulted from
separate acts of creation by the intelligent designer, while
admitting that fruit flies evolved from a common ancestor that lived
20 million years ago? The answer is that humans must at all costs not
be lumped in with other species, so as to protect the biblical status
of humans as uniquely created in God's image.

According to Pandas, the theory of "limits to evolution" is a
scientific one: "The idea of intelligent design does not preclude the
possibility that variation within species occurs, or that new species
are formed from existing populations . . . the theory of intelligent
design does suggest that there are limits to the amount of variation
that natural selection and random change mechanisms can produce." But
there is nothing in the theory of intelligent design that tells us
how far evolution can go. This "thus far and no further" view of
evolution comes not from any scientific findings of ID; it comes from
ID's ancestor, scientific creationism. Scientific Creationism notes
that "the creation model . . . recognizes only the kind as the basic
created unit, in this case, mankind," and a chart contrasting
evolution with the "creation model" says that the former predicts
"new kinds appearing," while the latter says "no new kinds appearing."

But what is a "kind"? No creationist has ever defined it, though they
are all very sure that humans and apes are different "kinds." In
fact, the notion that evolution and creation have operated together,
with the latter creating distinct "kinds," was nicely rebutted by
Darwin in On the Origin of Species:

Several eminent naturalists . . . admit that they [evolved species]
have been produced by variation, but they refuse to extend the same
view to other and very slightly different forms. Nevertheless they do
not pretend that they can define, or even conjecture, which are the
created forms of life, and which are those produced by secondary
laws. They admit variation as a vera causa in one case, they
arbitrarily reject it in another, without assigning any distinction
in the two cases. The day will come when this will be given as a
curious illustration of the blindness of preconceived opinion. These
authors seem no more startled at a miraculous act of creation than at
an ordinary birth. But do they really believe that at innumerable
periods in the earth's history certain elemental atoms have been
commanded suddenly to flash into living tissues? Do they believe that
at each supposed act of creation one individual or many were
produced? Were all the infinitely numerous kinds of animals and
plants created as egg or seed, or as full grown? and in the case of
mammals, were they created bearing the false marks of nourishment
from the mother's womb? Although naturalists very properly demand a
full explanation of every difficulty from those who believe in the
mutability of species, on their own side they ignore the whole
subject of the first appearance of species in what they consider
reverent silence.

In fact, the biblical appendix of Scientific Creationism shows that
the term "kind" derives from the biblical notion of created kinds:

The Scriptures are very clear in their teaching that God created all
things as He wanted them to be, each with its own particular
structure, according to His own sovereign purposes. The account of
Genesis 1, for example, indicates that at least ten major categories
of organic life were specially created "after his kind." . . .
Finally, man "kind" was created as another completely separate
category. The phrase "after his kind" occurs ten times in this first
chapter of Genesis.

There is thus a clear line of descent from the story of Genesis to
the ID notion of evolutionary limits, a line charted by what Darwin
called "the blindness of preconceived opinion." Until IDers tell us
what the limits to evolution are, how they can be ascertained, and
what evidence supports these limits, this notion cannot be regarded
as a genuinely scientific claim.

V.

IDers make one claim that they tout as truly novel, a claim that has
become quite popular. It is the idea that organisms show some
adaptations that could not be built by natural selection, thus
implying the need for a supernatural creative force such as an
intelligent designer. These adaptations share a property called
"irreducible complexity," a characteristic discussed in Pandas but
defined more explicitly by Michael Behe in 1996 in his book Darwin's
Black Box: The Biochemical Challenge to Evolution: "By irreducibly
complex I mean a single system composed of several well-matched,
interacting parts that contribute to the basic function, wherein the
removal of any one of the parts causes the system to effectively
cease functioning."

Many man-made objects show this property: Behe cites the mousetrap,
which would not work if even one part were removed, such as the
catch, the spring, the base, and so on. Pandas mentions a car engine,
which will not work if one removes the fan belt, spark plugs,
distributor cap, or any of numerous individual parts. A famous
example of an irreducibly complex system in the biological realm is
the "camera" eye of humans and other vertebrates. The eye has many
parts whose individual removal would render the organ useless,
including the lens, retina, and optic nerve.

The reason IDers love "irreducibly complex" features of organisms is
that natural selection is powerless (or so they claim) to create such
features. As Behe notes:

An irreducibly complex system cannot be produced directly ... by
slight, successive modifications of a precursor system, because any
precursor to an irreducibly complex system that is missing a part is
by definition nonfunctional.... Since natural selection can only
choose systems that are already working, then if a biological system
cannot be produced gradually it would have to arise as an integrated
unit, in one fell swoop, for natural selection to have anything to
act on.

"One fell swoop," of course, implies that the feature must have been
produced by the miraculous intervention of the intelligent designer.

But this argument for intelligent design has a fatal flaw. We have
realized for decades that natural selection can indeed produce
systems that, over time, become integrated to the point where they
appear to be irreducibly complex. But these features do not evolve by
the sequential addition of parts to a feature that becomes functional
only at the end. They evolve by adding, via natural selection, more
and more parts into an originally rudimentary but functional system,
with these parts sometimes co-opted from other structures. Every step
of this process improves the organism's survival, and so is
evolutionarily possible via natural selection.

Consider the eye. Creationists have long maintained that it could not
have resulted from natural selection, citing a sentence from On the
Origin of Species: "To suppose that the eye with all its inimitable
contrivances for adjusting the focus to different distances, for
admitting different amounts of light, and for the correction of
spherical and chromatic aberration, could have been formed by natural
selection, seems, I freely confess, absurd in the highest degree."
But in the next passage, invariably omitted by creationists, Darwin
ingeniously answers his own objection:

Reason tells me, that if numerous gradations from a simple and
imperfect eye to one complex and perfect can be shown to exist, each
grade being useful to its possessor, as is certainly the case; if
further, the eye ever varies and the variations be inherited, as is
likewise certainly the case and if such variations should be useful
to any animal under changing conditions of life, then the difficulty
of believing that a perfect and complex eye could be formed by
natural selection, though insuperable by our imagination, should not
be considered as subversive of the theory.

Thus our eyes did not suddenly appear as full-fledged camera eyes,
but evolved from simpler eyes, having fewer components, in ancestral
species. Darwin brilliantly addressed this argument by surveying
existing species to see if one could find functional but less complex
eyes that not only were useful, but also could be strung together
into a hypothetical sequence showing how a camera eye might evolve.
If this could be done--and it can--then the argument for irreducible
complexity vanishes, for the eyes of existing species are obviously
useful, and each step in the hypothetical sequence could thus evolve
by natural selection.

A possible sequence of such changes begins with pigmented eye spots
(as seen in flatworms), followed by an invagination of the skin to
form a cup protecting the eyespot and allowing it to better localize
the image (as in limpets), followed by a further narrowing of the
cup's opening to produce an improved image (the nautilus), followed
by the evolution of a protective transparent cover to protect the
opening (ragworms), followed by coagulation of part of the fluid in
the eyeball into a lens to help focus the light (abalones), followed
by the co-opting of nearby muscles to move the lens and vary the
focus (mammals). The evolution of a retina, an optic nerve, and so on
would follow by natural selection. Each step of this transitional
"series" confers increased adaptation on its possessor, because it
enables the animal to gather more light or to form better images,
both of which aid survival. And each step of this process is
exemplified by the eye of a different living species. At the end of
the sequence we have the camera eye, which seems irreducibly complex.
But the complexity is reducible to a series of small, adaptive steps.

Now, we do not know the precise order in which the components of the
camera eye evolved--but the point is that the appearance of
"irreducible complexity" cannot be an argument against neo-Darwinism
if we can document a plausible sequence in which the complexity can
arise from a series of adaptive steps. The "irreducible complexity"
argument is not, in fact, completely novel. It descends, with
modification, from the British theologian William Paley, who in 1802
raised the famous "argument from design" in his book Natural
Theology. Paley argued that just as finding a watch on the ground
implies a conscious designer (the watchmaker), so finding an equally
complex organism implies a cosmic designer (God).

But the eye is not a watch. The human eye, though eminently
functional, is imperfect--certainly not the sort of eye an engineer
would create from scratch. Its imperfection arises precisely because
our eye evolved using whatever components were at hand, or produced
by mutation. Since our retina evolved from an everted part of the
brain, for example, the nerves and blood vessels that attach to our
photoreceptor cells are on the inside rather than the outside of the
eye, running over the surface of the retina. Leakage of these blood
vessels can occlude vision, a problem that would not occur if the
vessels fed the retina from behind. Likewise, to get the nerve
impulses from the photocells to the brain, the different nerves must
join together and dive back through the eye, forming the optic nerve.
This hole in the retina creates a blind spot in the eye, a flaw that
again would be avoidable with a priori design. The whole system is
like a car in which all the wires to the dashboard hang inside the
driver's compartment instead of being tucked safely out of sight.
Evolution differs from a priori design because it is constrained to
operate by modifying whatever features have evolved previously. Thus
evolution yields fitter types that often have flaws. These flaws
violate reasonable principles of intelligent design.

IDers tend to concentrate more on biochemistry than on organs such as
the eye, citing "irreducibly complex" molecular systems such as the
mechanism for blood-clotting and the immune system. Like the eye,
these systems supposedly could not have evolved, since removal of any
step in these pathways would render the entire pathway non-
functional. (This biochemical complexity is the subject of Behe's
book Darwin's Black Box.) Discussing the blood-clotting system in its
sixth chapter (partially written by Behe), Pandas asserts that "like
a car engine, biological systems can only work after they have been
assembled by someone who knows what the final result will be." This
is nonsense. As we have seen in the case of the eye, biological
systems are not useful only at the end of a long evolutionary
process, but during every step of that process. And biochemical
systems--like all adaptations created by natural selection--are not
assembled with foresight. Whatever useful mutations happen to arise
get folded into the system.

There is no doubt that many biochemical systems are dauntingly
complex. A diagram of the blood-clotting pathway looks like a
complicated circuit board, with dozens of proteins interacting with
one another to one end: healing a wound. And the system seems
irreducibly complex, because without any of several key proteins, the
blood would not clot. Yet such biochemical systems evolved in the
same way that the eye evolved, by adding parts successively and
adaptively to simpler, functioning systems. It is more difficult to
trace the evolution of biochemical pathways than of anatomical
structures because the ancestral metabolic pathways are no longer
present. But biologists are beginning to provide plausible scenarios
for how "irreducibly complex" biochemical pathways might have
evolved. As expected, these systems involve using bits co-opted from
other pathways originally having different functions. (Thus, one of
the enzymes in the blood-clotting system also plays a role in
digestion and cell division.) In view of our progress in
understanding biochemical evolution, it is simply irrational to say
that because we do not completely understand how biochemical pathways
evolved, we should give up trying and invoke the intelligent
designer. If the history of science shows us anything, it is that we
get nowhere by labeling our ignorance "God."

VI.

Insofar as intelligent-design theory can be tested scientifically, it
has been falsified. Organisms simply do not look as if they had been
intelligently designed. Would an intelligent designer create millions
of species and then make them go extinct, only to replace them with
other species, repeating this process over and over again? Would an
intelligent designer produce animals having a mixture of mammalian
and reptilian traits, at exactly the time when reptiles are thought
to have been evolving into mammals? Why did the designer give tiny,
non-functional wings to kiwi birds? Or useless eyes to cave animals?
Or a transitory coat of hair to a human fetus? Or an appendix, an
injurious organ that just happens to resemble a vestigial version of
a digestive pouch in related organisms? Why would the designer give
us a pathway for making vitamin C, but then destroy it by disabling
one of its enzymes? Why didn't the intelligent designer stock oceanic
islands with reptiles, mammals, amphibians, and freshwater fish,
despite the suitability of such islands for these species? And why
would he make the flora and fauna on those islands resemble that of
the nearest mainland, even when the environments are very different?
Why, about a million years ago, would the designer produce creatures
that have an apelike cranium perched atop a humanlike skeleton? And
why would he then successively replace these creatures with others
having an ever-closer resemblance to modern humans?

There are only two answers to these questions: either life resulted
not from intelligent design, but from evolution; or the intelligent
designer is a cosmic prankster who designed everything to make it
look as though it had evolved. Few people, religious or otherwise,
will find the second alternative palatable. It is the modern version
of the old argument that God put fossils in the rocks to test our faith.

The final blow to the claim that intelligent design is scientific is
its proponents' admission that we cannot understand the designer's
goals or methods. Behe owns up to this in Darwin's Black Box:
"Features that strike us as odd in a design might have been placed
there by the designer for a reason--for artistic reasons, to show
off, for some as-yetundetectable practical purpose, or for some
unguessable reason--or they might not." And, discussing skeletal
differences between placental and marsupial mammals, Pandas notes:

Why were not the North American placentals given the same bones?
Would an intelligent designer withhold these structures from
placentals if they were superior to the placental system? At present
we do not know; however, we all recognize that an engineer can choose
any of several different engineering solutions to overcome a single
design problem. An intelligent designer might reasonably be expected
to use a variety (if a limited variety) of design approaches to
produce a single engineering solution, also. Even if it is assumed
that an intelligent designer did indeed have a good reason for every
decision that was made, and for including every trait in each
organism, it does not follow that such reasons will be obvious to us.

Well, if we admit that the designer had a number of means and
motives, which can be self-contradictory, arbitrary, improvisatory,
and "unguessable," then we are left with a theory that cannot be
rejected. Every conceivable observation of nature, including those
that support evolution, becomes compatible with ID, for the ways of
the designer are unfathomable. And a theory that cannot be rejected
is not a scientific theory. If IDers want to have a genuinely
scientific theory, let them propose a model that can be rigorously
tested.

Given its lack of rigor, one might expect that ID theory would not
inspire much scientific research. And there is virtually none.
Despite the claims of ID to be a program of research, its adherents
have published only one refereed paper supporting ID in a scientific
journal: a review of ID by Stephen C. Meyer, the director of the
Discovery Institute's Center for Science and Culture, which appeared
in the Proceedings of the Biological Society of Washington. This
paper merely rehashes ID arguments for why natural selection and
evolution cannot explain the diversity of life and then asserts that
intelligent design is the only alternative. It distorts the
evolutionary literature it purports to review, and it neither
advances new scientific arguments nor suggests any way that ID better
explains patterns in nature. Not surprisingly, the Council of the
Biological Society of Washington later disowned the paper because it
did "not meet the scientific standards of the Proceedings."

The gold standard for modern scientific achievement is the
publication of new results in a peer-reviewed scientific journal. By
that standard, IDers have failed miserably. As William Dembski
himself noted, "There are good and bad reasons to be skeptical of
intelligent design. Perhaps the best reason is that intelligent
design has yet to establish itself as a thriving scientific research
program." IDers desperately crave scientific respectability, but it
is their own theory that prevents them from attaining it. Thus, while
IDers demand that evolutionists produce thousands of transitional
fossils and hundreds of detailed scenarios about the evolution of
biochemical pathways, they put forth no observations supporting the
plausibility of a supernatural designer, nor do they show how appeal
to such a designer could explain the fossil record, embryology, and
biogeography better than neo-Darwinism. Herbert Spencer could have
been describing ID when he declared that "those who cavalierly reject
the Theory of Evolution as not being adequately supported by facts,
seem to forget that their own theory is supported by no facts at all.
Like the majority of men who are born to a given belief, they demand
the most rigorous proof of any adverse belief, but assume that their
own needs none."

Finally, the reliance of ID on supernatural intervention means that
the enterprise cannot be seen, strictly speaking, as scientific. In
his rejection of scientific creationism in McLean v. Arkansas, Judge
Overton described the characteristics of good science:

(1) It is guided by natural law;

(2) It has to be explanatory by reference to natural law;

(3) It is testable against the empirical world;

(4) Its conclusions are tentative, i.e., are not necessarily the
final word; and

(5) It is falsifiable.

By invoking the repeated occurrence of supernatural intervention by
an intelligent designer to create new species and new traits, ID
violates criteria 1 and 2; and in its ultimate reliance on Christian
dogma and God, it violates criteria 3, 4, and 5.

In candid moments, usually when writing for or speaking to a
religious audience, IDers admit the existence not only of
supernatural acts as a part of their theory, but also of Christian
supernatural acts. In a foreword to a book on creationism, Johnson
wrote: "The intelligent design movement starts with the recognition
that 'In the beginning was the Word,' and 'In the beginning God
created.' Establishing that point isn't enough, but it is absolutely
essential to the rest of the gospel message." And here is Dembski
writing in Touchstone, a Christian magazine: "The world is a mirror
representing the divine life.... Intelligent design readily embraces
the sacramental nature of physical reality. Indeed intelligent design
is just the Logos theology of John's Gospel restated in the idiom of
information theory." Indeed, in the manuscript draft of the first
edition of Pandas, the terms "creationism," "creationist," and
"creation" are used repeatedly instead of the equivalent ID terms,
and "creationism" is defined identically to "intelligent design" in
the published version. Nothing gives a clearer indication that one
ancestor of this textbook was the Bible.

It is clear, then, that intelligent design did not arise because of
some long-standing problems with evolutionary theory, or because new
facts have called neoDarwinism into question. ID is here for only one
reason--to act as a Trojan horse poised before the public schools: a
seemingly secular vessel ready to inject its religious message into
the science curriculum. The contents of Pandas, and of the other
writings of IDers, are simply a cunning pedagogical ploy to
circumvent legal restrictions against religious creationism. (With
any luck, though, the publicity will backfire. Last month The York
Dispatch in Pennsylvania reported that the Foundation for Thought and
Ethics, the group that publishes this textbook and others designed to
present "a Christian perspective," wanted to intervene in the Dover
lawsuit. According to John Buell, the foundation's president, the
association of ID with creationism "would make the book radioactive,"
and his outfit could lose as much as $525,000 in sales.)

ID is part of what Johnson candidly calls the "wedge strategy," a
carefully crafted scheme that begins with the adoption of intelligent
design as an alternative theory to evolution, after which ID will
edge out evolution until it is the only view left, after which it
will become full-blown biblical creationism. The ultimate goal is to
replace naturalist science with spiritualist thinking, and the method
is to hammer the wedge of ID into science at its most vulnerable
point: public education. In Johnson's own words:

So the question is: "How to win?" That's when I began to develop what
you now see full-fledged in the "wedge" strategy: "stick with the
most important thing," the mechanism and the building up of
information. Get the Bible and the Book of Genesis out of the debate
because you do not want to raise the so-called Bible-science
dichotomy. Phrase the argument in such a way that you can get it
heard in the secular academy and in a way that tends to unify the
religious dissenters. That means concentrating on, "Do you need a
Creator to do the creating, or can nature do it on its own?" and
refusing to get sidetracked onto other issues, which people are
always trying to do.

Johnson was even more explicit in 1999 in remarks to a conference on
"Reclaiming America for Christ." Rob Boston reported Johnson's
remarks in Church & State magazine:

Johnson calls his movement "The Wedge." The objective, he said, is to
convince people that Darwinism is inherently atheistic, thus shifting
the debate from creationism v. evolution to the existence of God v.
the nonexistence of God. From there people are introduced to "the
truth" of the Bible and then "the question of sin" and finally
"introduced to Jesus."

Other major figures in the ID movement have been equally clear about
their religious motivations. Here is Dembski:

But there are deeper motivations. I think at a fundamental level, in
terms of what drives me in this is that I think God's glory is being
robbed by these naturalistic approaches to biological evolution,
creation, the origin of the world, the origin of biological
complexity and diversity. When you are attributing the wonders of
nature to these mindless material mechanisms, God's glory is getting
robbed.

And here is Jonathan Wells, a member of Reverend Moon's Unification
Church:

Father's [Reverend Moon's] words, my studies, and my prayers
convinced me that I should devote my life to destroying Darwinism,
just as many of my fellow Unificationists had already devoted their
lives to destroying Marxism. When Father chose me (along with about a
dozen other seminary graduates) to enter a Ph.D. program in 1978, I
welcomed the opportunity to prepare myself for battle.

To these people really believe in intelligent design? There is no
reason to think otherwise. They are not lying for their cause, but
sincerely hold that life on earth reflects a succession of miracles
worked by a supernatural agent. In fact, they view evolutionists as
the duplicitous ones. In an interview in The Sacramento Bee in 1991,
Johnson proclaimed that "scientists have long known that Darwinism is
false. They have adhered to the myth out of self-interest and a
zealous desire to put down God." Never mind that many scientists,
including evolutionists, are religious.

Given the overwhelming evidence for evolution and the lack of
evidence for ID, how can intelligent people hold such views? Is their
faith so strong that it blinds them to all evidence? It is a bit more
complicated than that. After all, many theologians and religious
people accept evolution. The real issues behind intelligent design--
and much of creationism--are purpose and morality: specifically, the
fear that if evolution is true, then we are no different from other
animals, not the special objects of God's creation but a contingent
product of natural selection, and so we lack real purpose, and our
morality is just the law of the jungle. Tom DeLay furnished a
colorful example of this view on the floor of the House of
Representatives on June 16, 1999. Explaining the causes of the
massacre at Columbine High School, he read a sarcastic letter in a
Texas newspaper that suggested that "it couldn't have been because
our school systems teach the children that they are nothing but
glorified apes who have evolutionized out of some primordial soup of
mud."

The notion that naturalism and materialism are the enemies of
morality and a sense of human purpose, and that religion is their
only ally, is pervasive in the writings of IDers. As Johnson noted,
"Once God is culturally determined to be imaginary, then God's
morality loses its foundation and withers away." Nancy Pearcey, a
senior fellow of the Discovery Institute's Center for Science and
Culture, summarizes why evolution disturbs so many Americans:

Why does the public care so passionately about a theory of biology?
Because people sense intuitively that there's much more at stake than
a scientific theory. They know that when naturalistic evolution is
taught in the science classroom, then a naturalistic view of ethics
will be taught down the hallway in the history classroom, the
sociology classroom, the family life classroom, and in all areas of
the curriculum.

Even some parents in Dover, though opposed to teaching ID in school,
worry that learning evolution will erode the Christian values that
they are trying to instill in their children.

But the acceptance of evolution need not efface morality or purpose.
Evolution is simply a theory about the process and patterns of life's
diversification, not a grand philosophical scheme about the meaning
of life. Philosophers have argued for years about whether ethics
should have a basis in nature. There is certainly no logical
connection between evolution and immorality. Nor is there a causal
connection: in Europe, religion is far less pervasive than in
America, and belief in evolution is more widespread, but somehow the
continent remains civilized. Most religious scientists, laymen, and
theologians have not found the acceptance of evolution to impede
living an upright, meaningful life. And the idea that religion
provides the sole foundation for meaning and morality also cannot be
right: the world is full of skeptics, agnostics, and atheists who
live good and meaningful lives.

Barring a miracle, the Dover Area School District will lose its case.
Anyone who bothers to study ID and its evolution from earlier and
more overtly religious forms of creationism will find it an
unscientific, faith-based theory ultimately resting on the doctrines
of fundamentalist Christianity. Its presentation in schools thus
violates both the Constitution and the principles of good education.
There is no secular reason why evolutionary biology, among all the
sciences, should be singled out for a school-mandated disclaimer. But
the real losers will be the people of Dover, who will likely be
saddled with huge legal bills and either a substantial cut in the
school budget or a substantial hike in property taxes. We can also
expect that, if they lose, the IDers will re-group and return in a
new disguise even less obviously religious. I await the formation of
the Right to Teach Problems with Evolution Movement.

IDers have been helped by Americans' continuing doubts about the
truth of evolution. According to a Gallup poll taken last year, 45
percent of Americans agree with the statement, "God created human
beings pretty much in their present form at one time within the last
10,000 years." Asked if evolution is well supported by evidence, 35
percent of Americans said yes, 35 percent said no, and 29 percent
said they lack the knowledge to reply. As a rationalist, I cannot
help but believe that the first group would swell were Americans to
be thoroughly taught the evidence for evolution, which is rarely done
in public high schools. I have seen creationist students become
evolutionists when they learn about biogeography or examine the
skulls of mammal-like reptiles. What we need in the schools is not
less teaching of evolution but more.

In the end, many Americans may still reject evolution, finding the
creationist alternative psychologically more comfortable. But emotion
should be distinguished from thought, and a "comfort level" should
not affect what is taught in the science classroom. As Judge Overton
wrote in his magisterial decision striking down Arkansas Act 590,
which mandated equal classroom time for "scientific creationism":

The application and content of First Amendment principles are not
determined by public opinion polls or by a majority vote. Whether the
proponents of Act 590 constitute the majority or the minority is
quite irrelevant under a constitutional system of government. No
group, no matter how large or small, may use the organs of
government, of which the public schools are the most conspicuous and
influential, to foist its religious beliefs on others.

JERRY COYNE is a professor in the Department of Ecology and Evolution
at the University of Chicago.

RELATED LINKS
Creations
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