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by a gigantic meteorite,"
8
and The Strawman: "There was no big
dinosaur bone pile . . . that might have resulted from an instanta-
neous event."
9
(Scientists have shown that the K-T extinction would
not have produced large bone piles.] They resort to the Red Herring:
There "is a connection between livestock problems and the demise
of the dinosaurs,"
1
0
and plead for equal time: "Between 1991 and
1993 . . .
Science
published eleven articles favorable to [impact] and
two unfavorable."
1
1
They blame the media: "Before long the bias [of
Science]
was so evident to members of the Earth science community
that few even bothered to submit ... a manuscript that espoused
a terrestrial cause"
12
; and they impugn the motives of the pro-
impactors: "In degenerating [research] programs . . . theories are fa-
bricated only in order to accommodate known facts." They conclude
that the Alvarez theory is "not merely pathological science but dan-
gerous to boot."
1
3
In courtrooms, legislative halls, and debating tournaments, the
more determined and skillful an argument on one side, the more the
position of the other side is weakened. Even in the face of a moun-
tain of evidence, an adroit defense attorney can see a guilty man set
free. It would be reasonable to assume that Officer's long struggle
has weakened the Alvarez theory and that, one day, Officer may
overthrow Alvarez. But here we find another way in which science
differs: Far from weakening the Alvarez theory, Officer's dissent has
greatly strengthened it. Officer's papers were accepted and pub-
lished in respectable journals, requiring the pro-impactors to polish
up their thinking and respond. As a result, we now know far more
about the geochemistry of iridium than if Officer and others had
accepted from the start that it is indeed a marker of impact not
found in volcanic rocks. We now know much more firmly that mul-
tiple sets of planar deformation features are caused only by impact.
Blind tests have been conducted that otherwise would have been
deemed a waste of time.
With an irony worthy of Greek tragedy, Officer's tireless, obses-
sive battle has had just the opposite outcome than he intended; its
main effect has been to cause doubters to reserve judgment and to
wait for stronger evidence to support impact, which eventually came.
Today, hardly anyone other than Officer doubts the existence of the
Chicxulub crater, though, as noted, some paleontologists do doubt
that it is linked to the K-T mass extinction. Officer's role is different
from that of, say, G. K. Gilbert, or from the authorities who opposed
continental drift from the 1920s through the 1960s. When those
magisters pronounced that terrestrial craters were caused by gas
explosions from below, or that continents cannot move, research was
