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Re: What did Spinosaurus eat? New species of Lepidotes found

Cannot it be helpful to compare the spinosaur and crocodile ratios
also to animals which are mostly not submerged but mostly feed on
aquatic sources? Several birds came to mind, including the heron.

2011/2/25 David Marjanovic <david.marjanovic@gmx.at>:
>>  The oxygen isotope ratios for _Spinosaurus_ indicate that the body
>>  was immersed much of the time. Immersion in water reduces aerial
>>  evaporation and therefore decreases enrichment of 18-oxygen in body
>>  water.
> If it stood in water a lot, it was able to drink any time it wanted; and its
> food came from freshwater, too. Finally, how much water evaporates through
> sauropsid skin, and how much enters it by osmosis when a sauropsid is
> immersed?
> In total, I don't see a reason to expect different oxygen isotope ratios in
> spinosaurs and aquatic or semiaquatic crocodiles, unless metabolism has an
> influence (which, apparently, it doesn't).
> I'll reply to the biomechanics stuff later, I must urgently finish a grant
> proposal...