To: null and void
" See T. Rex and the Crater of Doom."
Could you provide the full reference? I'll see if I can find it.
T. rex and the Crater of Doom, by Walter Alvarez, Princeton University Press. ISBN 0-691-01630-5
Pages 86-89 give a brief description of the Signor-Lipps effect, and it's implications for determining the abruptness of an extinction event.
Simply, an abrupt die off will be clear if there are abundant specimens on one side of the fossil record, and none on the other, but rare specimens blur the die off date, and make it look gradual.
Foraminifera, very common, sharp discontinuity in the fossil record.
T. rex, known by a few specimens, no clear discontinuity in the record.
posted on 07/09/2004 10:39:40 PM PDT
by null and void
(Why is OUR oil under THEIR sand???)
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