The Cave Lion (Panthera spelaea and Panthera fossilis)

[Ghari Sher]

(11-05-2018, 10:50 AM)GrizzlyClaws Wrote:

(11-04-2018, 11:40 PM)Ghari Sher Wrote:

(11-04-2018, 12:00 PM)GrizzlyClaws Wrote:

(11-04-2018, 11:21 AM)tigerluver Wrote:

(11-04-2018, 10:44 AM)GrizzlyClaws Wrote:

(11-04-2018, 12:25 AM)tigerluver Wrote: @Wolverine , I have not read of the released measurements for those fossils since their photos showed up years ago. However, I am certain larger P. fossilis are already on record. Let's use an ideal 200 kg lion as the isometric comparison.

The formula is:

Mass (fossil) = (Measurement of fossil)/(Measurement of extant specimen)^3 * Mass of the extant specimen.

Firstly, the 484.7 mm Chateau skull (Marciszak et al. 2014). A 200 kg modern lion could have a skull about 380 mm long. Applying these numbers to the aforementioned formula results in a mass of 415 kg.

Next, the 465 mm ulna (Reichenau 1908). A 200 kg lion could have an ulna about 385 mm long. Calculate... this P. fossilis weighed 352 kg.

Finally, the giant 192 mm MTIII (Marciszak et al. 2014). A 200 kg lion could have an MTIII of 145 mm. Calculate... a whopping 464 kg. Perhaps this is somewhat of an overestimate if P. fossilis was even longer limb-wise than the modern lion, but we have no skeletons to support this assumption other than the fact that its descendant, P. atrox, was indeed proportionally longer limb-wise. Moreover, MTIIIs vary a lot between individuals in relation to body size/mass. Nonetheless, the specimen was likely no less than 400 kg.

Both the MTIII and ulna can be confounded by an increased cursoriality in P. fossilis but the former much more so. The elongated skull of P. fossilis can also confound the isometric comparison to a degree.

From the scant fossil record, it is quite apparent P. fossilis consistently produced what would be giants by modern standards. For instance, many of the fragmented mandibles were likely from skulls that exceeded 400 mm. By probability and comparison of samples, P. fossilis was likely larger than P. atrox as well. The excessively large long bones of P. fossilis also hint that 130-140 cm at the shoulder would be comfortably attained by some of the largest specimens.

@epaiva I will post some photos soon, sorry about the wait.

Was the 192 mm MTIII specimen larger than the Chateau skull?

If we use the respective body parts of a 200 kg lion as the samples, it does appear so.

Maybe the 192 mm MTIII specimen could acquire a skull close to 500 mm which is the absolute maximum for any Panthera specimen?

The MTIII is a difficult one. One issue is that when calculating the range of weights produced by isometry, the range I found was as low as 400 kg to as high a over 500 kg. In other words, the bone is not that well correlated to body size, but is nonetheless from a top 10 Panthera specimen. The second issue is that if P. fossilis is more cursorial, the MTIII would be proportionately elongated and isometrically comparing the bone to that of an extant lion will heavily overestimate the weight. Thus extrapolating other body parts is filled with uncertainty. A skull length range of 450-500 mm would not be illogical in my opinion.

The issue can be applied to the skull. P. spelaea had a big skull for its bones, bigger than the extant lion. For instance, the specimen is Sabol (2018) has a femur to skull ratio of 0.99, which is distinctly less than extant lion generally as the number in P. leo is over 1.00. That means while applying the 484.7 mm skull to P. leo ratios, we'd think the femur would be 500 mm. Likely in reality the femur of the specimen was 470-480 mm, which is not that much bigger than the largest P. spelaea (470 mm femur from Germany mentioned by Deidrich). Of course still absurdly gigantic, but not what P. leo comparisons would lead one to believe. Another confounding issue is that long snouts usually means proportionately longer skulls for a body mass/size. We know that P. fossilis did have a longer snout that P. spelaea, likely making the long bone to skull ratio somewhat lesser in P. fossilis as compared to P. spelaea, further decreasing long bone length extrapolations by a bit. It is for this reason I feel the 465 mm has been underestimated via isometry or the 484.7 mm skull at least overestimated. Unless P. fossilis is exceptionally cursorial, a 465 mm ulna should give a femur of around 480 mm, matching the 484.7 mm skull. Now one can see why mass estimations vary so much, there are too many confounding variables. These two specimens were likely body size-wise just about the same as the 480 mm Ngandong femur for these reasons. Mass is a whole different rabbit hole in its own as the tiger and lion lineages hold mass differently. I have lately avoided addressing the complex topic and just give pure isometry estimates but hopefully this makes sense.

As a whole, the closer the species temporally to an extant species, the more accurate the single bone estimates and vice versa.

As for the rank of the cursoriality for the Pleistocene pantherine cats, it could be something like that?

Panthera fossilis > Panthera atrox > Panthera spelaea intermedia > Panthera spelaea spelaea > Panthera tigris (Pleistocene)

On this issue, I have my own questions regarding Panthera spelaea.

Diedrich & Rothschild (2012) concluded that the cave lion was most likely a pursuit hunter based on bone exostoses on the brachialis muscle attachment point on two individuals, one from the Eemian and the other Weichselian, out of a considerable sample of bones (NISP=1208, MNI Unknown) indicating the use of the paw-sweep used in running, which apparently supports pursuit hunting, as opposed to extant lions which are ambush hunters:

Quote:Exostoses in Smilodon, H. crenatidens and H. latidens are found in the flexor tendons of the upper limb (Heald, 1989; McCall et al., 2003; Moodie, 1923; Shermis, 1983; Turner, 1997) and have been used as evidence for grappling behavior (Rothschild, 2011). The patterns of exostoses in P. l. spelaea have a different distribution (brachialis muscle, reflecting flexion activities), instead supporting the hypothesis of pursuit behavior. The distribution of exostoses (Fig. 7) and enthesial reaction otherwise identifies P. l. spelaea as a pursuit, rather than ambush predator.

However, Schellhorn (2014) concluded based on ulna dimensions that the cave lion bore adaptations closer to forest cats compared to the extant lion, i.e. seemed to be less cursorial, among other things.

Quote:The included fossil cats Dinofelis piveteaui, P. spelaea, and S. fatalis all distinctly plot within the closed or forest habitat in the scatter plots (Figs. 1b, 2e, f).

In this case the sample size was not impressive, only a single ulna was used in this analysis.

And as has been discussed in the literature before, e.g. Sabol (2018), the cave lion was more robustly built than the African lion, and does indeed share similarities to the tiger in some of its features, including in the limb bones.
By scaling the cats down to the same shoulder height, I compared P. atrox, P. leo, and P. spelaea skeletons to each other (left-right, the cave lion skeleton was digitally modified by a friend from an image from this article https://3dprint.com/216653/reconstructing-cave-lion/)

*This image is copyright of its original author

Looking side-by-side, P. spelaea looks somewhat similar proportionally to P. leo, but it is overall noticeably more robust. I don't know exactly what implications this would have for cursoriality, but intuitively one would think it to be a less cursorial, more ambush-oriented predator.

Indeed, assuming the hypothesis of a derivation from P. fossilis, a shortening of the cave lion's distal limbs can be inferred from @tigerluver's calculations on post #52, as we enter the late Pleistocene, which would suggest a reduction in cursoriality.

A similar situation is seen in the cave lion's main competitor, cave hyena (Crocuta crocuta spelaea) which also have shortened distal limb elements, relative this time to their extant counterpart, which has also been suggested to indicate a less cursorial mode of hunting, among other things:

Quote:The crural index (tibia length/femur length) in the skeleton of Los Aprendices is 0.74, which is similar to the values of Crocuta spelaea (0.75) and Pachycrocuta brevirostris (0.74) and clearly lower than in extant C. crocuta (0.82) (Palmqvist et al., 2011). The shortening of the tibia of C. spelaea suggests a less cursorial lifestyle. Also, such shortening could provide great power and more stability to dismember and carry large parts of carcasses without dragging (Spoor, 1985; Turner and Antón, 1996; Palmqvist et al., 2011).

https://www.researchgate.net/publication...o_Zaragoza
Of course this could also be an adaptation towards the colder climate, not just in the cave hyena but the coeval cave lion as well, to reduce the size of extremities. Cave paintings have suggested that the cat had smaller ears, an inference supported by the small ears of the cub remains, as well as the shortened tail found at least in infancy, so the scenario where limbs are also shortened does not seem implausible, but apparently this would happen alongside the retention of a cursorial mode of hunting - assuming the hypotheses of a derivation from fossilis AND the inferences of Rothschild & Diedrich (2012) are correct.

Some frozen finds, such as the steppe bison blue babe, suggest a similar hunting behaviour to the extant lion, though of course the duration of the chase is hard to infer in such cases:

*This image is copyright of its original author

(Multiple lions hunting Blue Babe is a bit speculative, but that's besides the point here. A great illustration by Anton, regardless).

Unfortunately I can only attach Schellhorn (2014)'s paper because WildFact won't let me attach the Diedrich paper, but I'll make a new post and attach it there.

Any thoughts on the level of cursoriality possessed by the Late Pleistocene cave lion? Particularly in regards to the hypothesis that they were pursuit hunters? The exact answer isn't clear to me, and this is the data that I can find.

Oddly, Panthera leo looks like the one with biggest skull when the shoulder height being equalized.

When it comes to the cursoriality, Panthera spealea spelaea from the late Pleistocene looks like the one with the lowest level, and it also attained a maximum weight of 300-350 kg, very reminiscent to the largest Manchurian tigers in the history. These two felines were also highly convergently evolved.

Panthera spelaea intermedia from the early late Pleistocene was even larger at 400 kg, with a higher level of cursoriality which is considered a more primitive trait and transitional phase closer to Panthera fossilis.

Panthera spelaea spelaea should be considered as the final stabilized form of the Cave lion family, looks like its ultimate goal was to evolve morphologically closer to Panthera tigris.

So what would your thoughts be on the conclusions of Rothschild & Diedrich (2012) of the lion being primarily a pursuit hunter? Reply