Freak Felids - A Discussion of History's Largest Felines

[tigerluver]

(06-29-2014, 09:36 AM)GuateGojira Wrote:

(06-28-2014, 10:34 PM)'tigerluver' Wrote: I've updated the felid chart. I found a specimen dubious and removed it. The weights look more probable to me. 

Question for all. Which bulkiness do you think the Ngandong tiger had, the Bengal or the Amur? Depending on that choice, one estimate is preferred over the other.

 

Mmmm, very hard question. The femur looks like that of the captive Amur tigers, the dimentions match, however the skull doesn't resemble the mainland tigers, but those of the Sunda. I think that they were probably more close to that of the modern Bengal tigers, but those from Nagarahole or Ranthambore, which are muscular but not extremely bulkier (like those of Kaziranga or Nepal).
 

I couldn't find any significant difference in the femur proportions between the two "Bengal" and three Amur specimens cited by Christiansen. Furthermore, I also learned that the only compatible measurement with the Christiansen data of Koenigswald's is total length. The two methods of measurement have a strong uncertainty between one another. The tiger's published dimensions have at least a +/- 1 mm uncertainty (this small amount has a strong effect on the resulting epicondylar index), while the Christiansen document only has an uncertainty of +/- 0.1 mm. It seems the method in the early 1900s was slightly different. Just take a look at the difference of Christiansen P. atrox measurements of the same skulls cited by Merriam and Stock. Even an easy dimension as total length is 0.5 -1 mm off it seems. This disparity isn't too harmful for the larger measurements, but is too strong at small measurements (width measurements) to produce a reliable comparison. 

(06-29-2014, 09:44 AM)GrizzlyClaws Wrote: The prime Baikal was also not very bulky, but very muscular.

I got a feeling that the only bulky prehistoric tiger would be the Wanhsien tiger.

Looking back at my notes I found the humerus and tibia might be the best reflectors of bulkiness. For example, the 230 kg tiger cited by Christiansen and Harris had the thinner femur and ulna, but thickest humerus and tibia. I took the height and length of the specimens and found what one could call "planar surface area." Related weight to that value to find the bulkiness. The specimen with the most robust humerus and tibia and thinner femur and ulna was the bulkiest. 

Though, there is one glaring problem with Christiansen's data. Comparing them to wild specimens shows specimens with awkward weights. The largest lion he records was probably overweight and these tigers probably underweight. Taking into account a study that discussed obesity causing thickening of bones and Ursus's conclusion that some thinner bones had more muscle mass around them, this is one convuluted mystery. And it gets worse.

Regardless, Hooijer stated that the length-width index was exactly tiger-like, so there's no evidence in favor of the Wahnsien variety being bulkier based on the observation above. Interestingly, the length-width index for tiger subspecies cited by Hooijer is essentially the same across the island and mainland subspecies. That makes me wonder, is there even a reliable way to gauge the bulkiness of tigers through long bones? For sure the larger specimens are bulkier, the length data I posted earlier proves it. It just won't reflect in the bones on record. Of course, this mystery is only for Panthera and tigers especially as variation is relatively little. Smilodon is a totally different beast.

Finally, my opinion is that the 480 mm Ngandong tiger was relatively bulkier than the modern tiger. The longer the cat, the bulkier it is, it just comes with the territory. Even without looking at the numbers, the Terai tigers seem quite long compared to other tigers, and as Guate stated, they're relatively bulkier.



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