Re: Resources, energetics and dinosaur maximal size

[don ohmes <d_ohmes@yahoo.com>]

--- On Tue, 7/28/09, Richard W. Travsky <rtravsky@uwyo.edu> wrote:

> On Mon, 27 Jul 2009, Jura wrote:

>> McNab operates under the assumption (laid out in the
>> paper) that the largest terrestrial mammal known to have
>> existed (_Paraceratherium_ sp.), was probably operating at,
>> or near the maximum FMR for terrestrial animals in a
>> terrestrial ecology. In this case, it would be about
>> 170,0000 calories a day. The largest dinosaurs were about 8
>> times the size of _Paraceratherium_. If they were given a
>> mammalian metabolism, and concomitant FMR (as detailed in
>> the paper) then a 56 tonne _Brachiosaurus altithorax_ would
>> have to digest some 561,000 calories a day. This is asking a
>> lot for plant productivity of any time period.

> It's asking a lot of the animal involved. That's a lot of
> eating and effort.

At 4 "calories" per gm, and assuming 100% utilization of fibrous carbs, "561k 
calories" is only about 140kg per day of feed (assuming equivalent units).
This is obviously do-able acquisition-wise, but assuming 10% digestion of fiber 
is maybe not-so do-able...

Is it possible that micro-analysis of sauropod coprolites could get an estimate 
on what the fiber content of sauro-dung might have been?