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Tucked into the Canadian Rockies, 8000 feet
above sea level, is a small limestone quarry formed 530
million years ago called the Burgess Shale; less than a
city block long and only ten feet high, the Burgess Shale
holds the remains of an ancient sea that nurtured more varieties
of life than can be found in all of our modern oceans. Here
lived dozens of creatures never seen before or since --
creatures perfectly preserved in awesome detail, including
the five-eyed Opabinia and Anomalocaris whose
mouth was a circular nutcracker.
The early-twentieth-century discovery of
the Burgess Shale by Dr. Charles D. Walcott, head of the
Smithsonian Institution, could have thrown traditional scholarship
on evolution into confusion. How to account for such abundance
and yet not give up the received wisdom of past efforts
to classify the things of the earth? The task fell to Walcott,
widely conceded to be the greatest paleontologist of his
day. Unable, however, to read the exciting new message locked
in those fossils, Walcott made a tortured effort to accommodate
many truly unclassifiable forms of life within the standard
system. He misinterpreted these peculiar fossils and shoehorned
all Burgess animals into the conventional categories of
worms and arthropods. And there the matter stood until Professor
H. B. Whittington reinterpreted forms that had lain in laboratory
drawers for over forty years.
The story of why Walcott failed -- how he
could not have succeeded given his time and his past --
and how and why Whittington did succeed tells us much about
science and society -- and about ourselves. For it is our
view of life that shapes us.
What icon of existence do we follow? What
pictorial representation of life? Is the past a ladder of
progress, moving ever onward and upward? Or is evolution
the story of an inverted cone, small in the kinds of life
at the bottom and steadily widening, diversifying? These
are the conventional and comfortable pictures of life's
history, but the Burgess Shale teaches us instead that evolution
produced an incredibly prolific bush that spread its branches
suddenly half a billion years ago and has ever since seen
bits of life fall away. The falling away has the character
of a lottery -- many called, few chosen and for no particular
reason of superior anatomy.
The story of the Burgess Shale also holds
the story of Stephen Jay Gould's intense personal and intellectual
struggle with the nature of history. Play the tape of life
again starting with the Burgess Shale, and a different set
of survivors -- not including vertebrates this time -- would
grace our planet today. In this masterwork Gould explains
why the diversity of the Burgess Shale is important in understanding
this tape of our past and in shaping the way we ponder the
riddle of existence and the awesome improbability of human
evolution. The telling of this tale displays all of the
strength, depth, and grace unique to Stephen Jay Gould.
Stephen Jay Gould, who was among the
first recipients of a MacArthur Fellowship and whose books
have won many prizes, including the National Book Award,
teaches biology, geology, and the history of science at
Harvard University.
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