Were we designed or evolved?
THIS will be the first of three
columns I’ll write on evolution, creationism and
so-called intelligent design. We’ll start at a place
called Ellesmere Island, which lies north of
Greenland. Vikings explored Ellesmere Island more
than 1,000 years ago, but it was way too cold, even
for them. And it still is, for almost everybody.
It’s as big as Nebraska, with a population of only
168 people. But in 1999, University of Chicago
paleontologist Neil Shubin went there anyway, to
hunt for a fossil link between land animals and the
swampdwelling fishes from which land animals first
evolved. You’d think the Arctic Circle would be a
terrible place to hunt for fossils of swamp animals.
But in 2004, Shubin’s team dug up the skeleton of a
creature they gleefully called a “fish-a-pod.” They
gave it the scientific name, Tiktaalic. It had
the tail fins, gills and heavy scales of a
lobefinned fish. But it had the ribs and neck of an
amphibian. Its head had fish and amphibian
characteristics. And it had front legs, with
lizard-style leg bones and wrist joint, but fins
instead of toes. It breathed water but could crawl
onto land and feast on the huge bugs, which also
left fossils there. Shubin knew Ellesmere Island
would be a good place to hunt for this “missing
link,” because he’d done his homework on
evolutionary theory and continental drift. Swamp on
equator Three hundred seventy-five million years
ago, Ellesmere Island was a swamp on the earth’s
equator. Geologic evidence showed how it had slowly
moved north due to continental drift. Cold though it
is, its tropical past makes it a perfect “missing
link” hunting ground. Shubin’s team found its
proof as surely as detectives following clues at a
crime scene. If you want to say they’re wrong — then
you have to explain how swamp fossils got up to the
Arctic Circle, and how Shubin knew to search for
them there. Basically, that’s all science is. You
observe the evidence, you try to explain how it got
there and then you make a prediction to test your
explanation. Then you look for more evidence to
confirm or refute the prediction. We test
scientific theories every time we use modern
technology. If I flip a light switch, I can almost
always predict the light will go on. The theory of
electricity has long since been proven (even though,
like evolution, it’s “just” a theory.) It’s not a
matter of mental attitude or faith. It depends
totally on the wiring. Back at Ellesmere Island,
lobe-finned fishes used their front fins to push
themselves up off swamp bottoms to gulp air at the
surface. Tiktaalik’s ancestors used those fins to
pull themselves ashore. Fins slowly evolved into
legs and the lobe-fins’ air sacs evolved into lungs.
On land, Tiktaalic could escape its enemies and find
lots of food. Huge advantages that propelled the
evolutionary process. Nothing random about it.
The same thing happened with feathers, which
dinosaurs used for insulation long before birds
adapted them for flight. And the human throat, which
Lucy and other early hominids used for swallowing
and grunting, but we now use for human speech.
Theory testable Evolutionary theory and
continental drift are testable. That is, they let
you predict what you’ll find if you do further
research. Shubin used them to predict what his team
would find in a seemingly outlandish place such as
Ellesmere Island. Their prediction was 100 percent
correct. Theory proven, once again. Again, that’s
all science is. You observe; you develop a theory,
and then you make a prediction based on the theory.
If predictions are consistently correct, the
theory’s also correct. Shubin’s prediction was
correct. So were Charles Darwin’s. (Like, say, that
the earliest human ancestors would be found in
Africa.) Creationism, on the other hand, doesn’t
use predictions and testing. Creationism uses
strategy. The creationist says, “I must enforce
the Infallible Word — by whatever means necessary.”
If a prediction turns out to be wrong, creationist
think tanks use strategy to explain mistakes. For
150 years, creationists have predicted that no
“missing links” would be found. But we’ve been
finding them all that time. Archaropteryx is a link
between birds and reptiles. Lucy is a link between
humans and apes. (There are plenty more.) Tiktaalik
is a link between fish and amphibians. Ambulocetus
is a link between whales and land mammals. And there
are hundreds more. Evolutionary theory predicted
they would all be found. Creationism predicted they
wouldn’t. Who was right? Creationist think tanks
can only pretend such fossils don’t exist, even
though they do — or make a new excuse each time one
is found. But they can’t keep the darned things from
turning up. In my next column, I’ll talk about
how creationism does in the courts. The Rev. Dennis
McCarty is a Unitarian Universalist minister in
Columbus. His opinions are his own, and not
necessarily shared by members of his church. He can
be reached by e-mail at columnists@therepublic.com