Freak Felids - A Discussion of History's Largest Felines

[tigerluver]

(11-13-2018, 01:25 AM)Wolverine Wrote:

(11-10-2018, 10:51 PM)tigerluver Wrote:

(11-10-2018, 11:44 AM)GuateGojira Wrote:

(11-09-2018, 10:32 AM)tigerluver Wrote: On shoulder heights, I'd like to add some input based on actual bone data as most sources skip over that. Do not use weights as we can all see mass estimates are clearly unreliable and rather use long bone measurements for body size reconstruction. For the specimens we've recorded, all three giants likely reached around 130 cm. Nonetheless, based on probability it is quite likely there were a good amount of 140 cm P. fossilis we have not yet excavated. It was likely longer legged than modern cats (with distal limb elongation), meaning the largest of the bones are going to produce a very, very tall cat proportionately. One needs to understand that a 465 mm ulna and 192 mm MTIII are truly out of this world, no modern cat compares. Again weight and shoulder height are two different aspects.

The next point would be contrary to the conclusion of @GuateGojira. The largest bones of P. spelaea (470 mm femur, 475 mm skull which would be from a cat with a femur of around 465-470 mm), fall short of the 480 mm P. t. soloensis femur, meaning P. spelaea would likely be shorter. With the greater amount of P. spelaea specimens showing that the species was not really any smaller than P. atrox, P. atrox was likely about the same height as P. spelaea, perhaps somewhat taller for improved cursoriality. On this last point, maybe a chart showing the range of bone sizes of P. atrox and P. spelaea is in order to get P. spelaea its rightful recognition for its massive size.

I think that you know much more about the cave "lion" fossils that I, so your conclutions are much better than mine. I estimated that the cave "lions" and Panthera atrox were higher at shoulders that the Ngandong tigers just because I followed the general idea that tigers are normally "shorter" at the shoulders than lions on average, but to be honest, if the diference in the modern records is close to nothing, the same may happen with the Pleistocene specimens.

So, according with this, Panthera fossilis is still the largest cat, followed by Panthera tigris soloensis, and latter there is a tie between Panthera atrox and Panthera spelaea. Am I correct?

In terms of shoulder height, I agree. The P. fossilis distal long bones indicate that the cat reached unimaginable shoulder heights. In terms of mass and body length, the 480 mm femur should be able to match or exceed the largest P. fossilis in these regards if we assume the Ngandong specimen maintained the body length/mass to bone measurement ratio as modern tigers, which hold quite a bit of extra weight for bone measurements than lions and leopards (probably due to being proportionately longer in the axial skeleton and not robusticity). To match a 480 mm tiger femur in weight, a lion-like cat would need to have a femur of over 500 mm. The ulna and skull probably do not reach this value but the MTIII could get close.

I remember a long arguments in some European forums about the real body mass of that P.t.soloensis with 480 mm femur. There was a table with weight assessment (I think from proffesional palaeontologists, not sure) of that specimen of 480 kg. But than many guys noticed how come a cat with so gracile bones could weight 480 kg, "that's a bullshit". Somehow in internet snicked that photo with the tampered femur, I have no idea who tampered and why - intentionally or non-intentionally. The weight of the soloensis was reassessed to 340-370 kg by some bloggers.
Now seeng the original photos of Koenigswald you posted it looks like the animal had more robust body building and maybe we have to return to idea of much higher body mass. @tigerluver as a professional paleontologist what is your assessment of the body mass of P.t.soloensis with 480 mm femur if we assume that it was only a tiger subspecie? Do you try to say that Panthera tigris soloensis was rival of Panthera fossilis in term of body mass?

So the controversy behind the femur is based on the fact that the proximal (94 mm as published by vK) and distal measurements (88 mm as published by vK) seem small for the length of the bone. Early in memory, this was used as an opportunity to edit vK's table and convert the 480 mm length into 408 mm. This was quickly exposed and fortunately corrected. The tampered images seem to have been done so to force the photograph of the femur to match the proximal and distal widths to what was in the vK's table. 

I investigated vK's works and the photograph to learn vK's style of measurements. vK unfortunately never detailed his methods, however he did often refer to some measurements as diameters and others as (greatest) breadths. This is likely reason to believe he defined breadth and diameter somewhat differently. I came to the conclusion that vK did not measure true greatest width in the "Felis paleojavanica" bones, but rather diameters. A diameter is of course defined by the distance from point A to point B in a straight line.

Now we need to remember that vK is a legendary paleontologist who focused on hominins. For my next point, here is the human femur:

*This image is copyright of its original author

*This image is copyright of its original author

Note that in the human femur, the epicondyles are wider than the condyles and generally distal diameters and breadths are taken near the adductor tubercle to produce the greatest width of the epiphysis. This usually works well for cats too and vK likely measured in this fashion. However, the Ngandong femur does not follow this convention. 

*This image is copyright of its original author

Note how in Smilodon (and most cats, including extant tigers), the epicondylar area (the top of the distal femur) is clearly broader than the condylar area (the lower part of the distal femur). Conversely, the epicondylar area of the Ngandong femur is much thinner than the condylar area. Now take a look at the scale overlayed in the above image. If you measure from about the adductor tubercle in a straight line to the lateral side, you get the reported distal diameter of 88 mm. However, this is not the femur's true greatest distal width.

Similary, vK's proximal diameter is likely not the greatest diameter. For one, the photo shows one possible way he took it. Moreover, the sagittal diameter reported by vk of 59 mm makes a 94 mm greatest width of the proximal epiphysis impossible. I cannot say whether the sagittal diameter of the proximal was taken from the femoral head or somewhere else, but what I can say is that is extremely thick. Take a look at this chart from Merriam and Stock (1935):

*This image is copyright of its original author

Note the anteroposterior (AP) diameter of the femoral head. The largest diameter is 54.3 mm. Generally, the sagittal/AP diameter of the femoral head is often the thickest point of the proximal femur. So lets assume vK's measurement is from the femoral head as well. At 59 mm, the proximal femur is quite a bit more robust than even the largest P. atrox. Therefore, this points strongly against the Ngandong femur being lanky.

Here's another measurement for evidence. vK reported the width of the intercondylar fossa to be 23 mm on the inferior aspect of the distal femur. In a 225 kg tiger, the same measurement is around 17 mm. That's a massive 35% difference. The Ngandong femur was exceptionally robust distally.

On mass, we'll use isometry again. Via just the femur length, we have (assuming a 405 mm femur is from a 220 kg tiger):

Ngandong femur mass = (480 mm/405 mm)^3  * 220 = 366 kg

Now if we use the intercondylar fossa diameter we have (assuming a 17 mm intercondylar fossa is form a 220 kg tiger):

Ngandong femur mass = (23 mm/17 mm)^3  * 220 = 545 kg

Thus, the mass based on the bone length is likely an underestimate and the mass based on the intercondylar fossa width is an overestimate. For the purposes of giving a number in this post, we can average the two values together for a mass of 456 kg.

It is my opinion that the Ngandong tiger at least matched the mass of P. fossilis and the 480 mm femur specimen may have very well outweighed P. fossilis slightly if it had extant tiger proportions. 

While up until now the Ngandong femur has been considered to be the largest tiger we have found, it's very likely moving to second place. The Padang mandible we have talked about is building up to monstrous proportions but specifics will be given at a later date. @GrizzlyClaws made a good comparison with the mandible of the 458 mm P. atrox specimen in this post.

To end, here is a comparison of the Ngandong femur with an extant tiger femur:

*This image is copyright of its original author

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