How would a supernova be linked to the observed absence of
terrestrial vertebrate fossils for a meter or so below the
K/T boundary? This blank, errasing the fossil remains of
dinosaurs (which did not survive) and mammals (which did),
but not of plants, is now laid at the foot of acid rain due
to a huge quantity of sulfur thrown into the atmosphere.
Una Smith una.smith@yale.edu
Dept. of Biology, Yale Univ., New Haven, CT 06520-8104