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K-T extinction rate, percentages etc.
Good day to all list members,
When I was recently reading through my czech translation of a great D. M.
Raup's book "Extinction: Bad Genes or Bad Luck?" I've come upon a table of K-T
extinction numbers for various vertebrate groups (Raup's source is William
Clemens data collected from the western USA(?). It looks like this:
Columns from left to right: Taxon - number of genera before the (K-T) event -
number of extinct genera past the event - percentage of extinct genera
"PISCES"
Chondrichthyes 5 3 60%
Ostheichthyes 13 5 38
"AMPHIBIA" 12 4 33
"REPTILIA"
Chelonia 18 2 11
Eosuchia 1 0 0
Crocodilia 4 1? 25?
Eolatacertilia 1 1 100
Lacertilia 15 4? 27?
Serpentes 2 0? 0?
Saurischia 8 8 100
Ornithischia 14 14 100
Pterosauria ? ? 100
"AVES" ? ? ?
"MAMMALIA"
Microtuberculata 11 4 36
Marsupialia 4 3 75
Placentalia 9 1 11
TOTAL 117 50 43%
These values are from 1990 (?) or even older, so I suppose there were some new
finds and hence the table would change considerably. My question is: can anyone
share URL or does anyone even have an up-to-date info on this? Or any other
updated similar table on the K-T extinction situation? Thanks in advance. Also,
as the book is quite well known, what's the general opinion on this 43 %
extinction value for vertebrates (and how does it correspond with the overall
value of 65-70% for all K-T biota?) What was the situation in Hell Creek?
The same for another table from the same book:
K-T extinction event
Taxonomical (Linnean) unit Losses (in percents)
Phyle(-um) 0 %
Classes 1
Orders 10
Families 14
Genera 38
Species 65-70
Individuals ?
Values from around 1990. Are there any more accurate up-to-date calculations?
Thanks for any info, in advance Vlad
"Raptor sacra res raptori"
http://blog.lide.cz/Bakker/