[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Largest Camarasaurus specimens

In Greg Paul's Field Guide, the largest C. supremus specimen is listed at 18 
meters long and 23 tonnes. If C. supremus scaled up isometrically, then a 23 
meter long C. supremus would be (23/18)^3=~2.08 times as massive, or ~47.98 
tonnes. I'm not sure how accurate Greg's plasticine models are as they are not 
reproducible, but even if his original mass estimate was 15% too high (so 
instead of 23 tonnes, 19.5 tonnes), you still get a mass estimate of roughly 40 
tonnes for the 23-meter animal.

On the other hand, many if not all of Greg's mass estimats are problematic. A 
GDI volume estimate of Supersaurus based on Scott Hartman's skeletal gave me a 
roughly 24 tonnes, which is only about 2/3 the mass that is listed in the Field 
Guide. Maybe and 18-meter C. supremus was "only" 15 or 16 tonnes, not 23 tonnes.

My question is: where does the 23 meter-long Camarasaurus estimate come from? 
Wikipedia lists the reference as Foster, J. (2007). Jurassic West: The 
Dinosaurs of the Morrison Formation and Their World. Indiana University Press. 
p. 201 (which I do not have). Google books only gives a snippet preview so I 
can't check.

----- Original Message -----
> From: David Marjanovic <david.marjanovic@gmx.at>
> To: DML <dinosaur@usc.edu>
> Cc: 
> Sent: Tuesday, May 22, 2012 4:38 PM
> Subject: Re: Largest Camarasaurus specimens
>>   Does any one have any references for the largest Camarasaurus
>>   specimens (especially C. supremus). I've heard size estimates of 23
>>   meters long and 47 tonnes
> I have no idea, but I can say with a fair amount of certainty that 47 tonnes 
> for 
> a 23-m-long animal that is not a whale is ludicrous. 10 t, OK; 20 t, OK; 30 
> t, 
> if it's proportioned like a sumo wrestler, why not. 47 t? No way.
> I guess this figure was derived by measuring the water displacement of a 
> commercial model that violated Holtz's First Rule of Skeletal Restoration*, 
> using the rounded density of an unspecified lizard.
> * "If the skeleton doesn't fit inside the model, the model is 
> wrong."