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re:GSP & dinosaur growth



     Greg Paul said:(just the parts I wondered about)
     <snip>
     Let us turn to Ruben's 1995 claim that Troodon grew no more rapidly 
     than Alligator, which is based on misleading manipulation of the data 
     (his idea of comparing growth in full grown dinosaurs to still growing 
     reptiles not only distorts the comparison, but is impractical because 
     we do not now at what % of final size most dinosaurs become fecund). 
     The theropod may have grown to 50-70 kg in 3-5 years assuming bone 
     rings were annuli (faster growth is suggested if the deep set rings 
     were multi-annular, as they are in some mammals).
     <snip>
     Ruben neglected to note that Reid 1987, 1990 has used bone rings to 
     estimate that A) the ornithopod Rhabdodon grew faster than crocs (to 
     ~300 kg in 10-15 years), and B) a sauropod died at a mass of about 8 
     tonnes at age 28-29.
     <snip>
     Assertions that fully terrestrial reptiles can somehow manage to grow 
     as fast as a number of dinosaurs seem to constitute further examples 
     of unsubstantiated, untestable, speculative arm waving. The inability 
     of juvenile land reptiles to grow fast may be another reason why only 
     mammals and dinos with high metabolic rates grow gigantic on land 
     (Ruben is correct that sharp declines in metabolic rates upon 
     cessation of growth are improbable). 
     <snip>
     
     How do the growth patterns of Troodon you site compare with J Horner 
     and Mary wass-her-face's study (ALL my dino refs are packed, sorry) of 
     Maiasaur growth patterns.  As far as I know, this is the only reliable 
     growth study as samples exist for all ages, which is not seen yet in 
     Troodon.
     Do you support the idea that dinosaurs seem to have a high metabolism 
     in their young-and-growing phase, and then seem to slow down their 
     metabolism as they reach full size, shown by Horner and wassherface by 
     growth rings and pockets in the bone sampled from an entire selection 
     of ages of Maiasaur?
     
     
     Betty Cunningham
     (bcunning@nssi.com at work)
     (bettyc@flyinggoat.com in the studio)