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Extinction again and again and again...



More on the regression that did not cause the K-T extinction:

Peter D. Ward, quoted in
James Lawrence Powell: Night Comes to the Cretaceous: dinosaur extinction
and the transformation of modern geology, W. H. Freeman 1998:
"We just do not know how a regression could kill anything."

In the same book the sea level is plotted against time. In the middle
Oligocene, when Antarctica froze over, the sea level dropped by _400 m_, and
there was no mass extinction. On other occasions, too, sea level dropped
quickly by several 100 m, but never at the same time as a mass extinction.

In southern France, hadrosaurs (and new vegetation) appeared suddenly a few
million years before the K-T boundary, apparently because the sea level had
fallen enough to make western Europe dry land connected to Euramerica, and
titanosaurs may have vanished. Dinosaurs as a whole, however, show no sign
of crisis and die off all at once at the K-T boundary. "Et elle [their end]
fut sans doute brutale!"
Reference:
Rachel Fléaux: À la recherche des mondes perdus, Sciences et avenir Mai
1999, p. 50f.
------"-------- De l'Aude au Jura, une friche à fossiles, same issue, p.
58f. (an interview with Éric Buffetaut)