Dinosaur Killer - Four Revolutions in the Earth Sciences - page 176

Dinosaur Killer
Paleoweltschmerz
In 1980, a paper appeared in Science titled “Extraterrestrial Cause for the
Cretaceous-Tertiary Extinction.” 1 The authors were the father-son team of Luis
and Walter Alvarez, together with their University of California colleagues Frank
Asaro and Helen Michel. The Cretaceous-Tertiary boundary, known as the K-T, is
the point in geological time at which the dinosaurs and 70 percent of all species
became extinct, one of the five big mass extinctions in earth history. 2
Though none of the four authors was a paleontologist, they claimed to have
solved one of the most venerable puzzles of the fossil record: what killed the
dinosaurs? There was no lack of proposed explanations. In a 1964 article titled
“Riddle of the Terrible Lizards,” the paleontologist Glenn Jepsen tallied the scores
of proffered theories, which ranged from “evolutionary drift into senescent over-
specialization” to “ paleoweltschmerz ,” a prehistoric world-weariness. 3 Whatever
one might think of these proposed solutions individually, few if any could explain
the simultaneous extinction of giant terrestrial dinosaurs and microscopic marine
organisms like foraminifera.
If lunar scientists could joke that they had proved that the Moon cannot exist,
paleontologists might have joked that they had proved that the great dinosaurs still
do exist. What no one could have imagined is that the origin of the Moon and the
demise of the dinosaurs over four billion years later would turn out to have the
same fundamental cause.
A New Destructive Force
Luis Alvarez (1911-1988) was one of the most distinguished physicists of the
twentieth century. During World War II, he worked with Robert Oppenheimer on
the Manhattan Project. In July 1945, Alvarez flew above the New Mexico desert to
observe Trinity, the first atomic bomb test. On August 6 he was aboard the Great
Artiste , the companion plane to the Enola Gay , on its fateful flight over Hiroshi-
ma. Thus Luis Alvarez was a rare witness to both of the first two atomic bomb
explosions. On the return flight from Hiroshima, he wrote a poignant letter to his
young son Walter expressing his hope that the “new destructive force,” so much
more powerful than conventional weapons, would realize Alfred Nobel's dream