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microfossils, studied forams at the K-T sections at El Kef, Tunisia,
and along the Brazos River in Texas. At Snowbird II, Keller reported
that "planktonic foraminifera show 30-45% of the species disap-
pearing during the 300,000 to 400,000 years prior to the K-T
boundary. . . . [They] show an extended K-T boundary extinction
pattern beginning below and ending well above the boundary."
2
8
If
confirmed, this would falsify both predictions 1 and 2 for the fo-
rams. But Smit, in contrast to Keller, did not find that any forams
disappeared before the boundary.
Here we have an impasse. Two reputable scientists, each exam-
ining the fossils from the same section of rock, come to entirely dif-
ferent conclusions. What to do? The answer was to conduct a blind
test in which samples are carefully collected under the supervision
of a neutral party and then distributed to other experts, who iden-
tify the fossils without knowing from where in the section they
come. New samples were collected at El Kef and distributed by
Robert Ginsburg of the University of Miami to four independent
specialists, not including either Keller or Smit.
Ginsburg was to present the results of the blind test on the El
Kef samples at Snowbird III. Keller had departed the night before,
and Ginsburg, returning from the excursion to Mimbral, fell down
an escalator. He prevailed upon Fischer to present the results and
flew home.
2
9
Richard Kerr reported that, after Snowbird III, "both
sides claimed victory."
3
0
Keller argued that each of the four investi-
gators had found that at least some fraction—ranging from 2 percent
to 21 percent—of the Cretaceous forams had gone extinct before
the boundary, which essentially confirmed that the extinctions were
gradual. But Smit disagreed, telling Kerr that this was a typical
Signor-Lipps effect. Smit then lumped together the results from all
four investigators, but using only species that at least two of them
had found. Each species that Keller said had disappeared before the
boundary, Smit's technique located in the last sample immediately
below it. Smit summed up: "Taken together, they found them all.
This eliminates any evidence for preimpact extinction in the [open
ocean] realm."
3
1
Keller responded that if some of the investigators had been mis-
taken in their identifications and had lumped together species that
looked similar but were not, then what was actually a series of grad-
ual extinctions would appear to have been sudden. But as Kerr
reports, Keller's own taxonomy came into question. Brian Huber of
the U.S. National Museum of Natural History had studied and writ-
ten about the forams in a deep-sea sediment core (from Ocean
Drilling Program Site 738), on which Keller subsequently published.
