There is a world somewhere between reality and fiction. Although ignored by many, it is very real and so are those living in it. This forum is about the natural world. Here, wild animals will be heard and respected. The forum offers a glimpse into an unknown world as well as a room with a view on the present and the future. Anyone able to speak on behalf of those living in the emerald forest and the deep blue sea is invited to join.
All numeric references can be found in my earlier two posts.
Built of Xenosmilus hodsonae
The overall body orientation of X. hodsonae is posteriorly sloped, similar to S. populator. Its long bones were considered more robust than even S. fatalis in cases by Naples et al. (2011). However, when looking at more specimens, this does not hold true consistently. X. hodsonae is generally most robust than the lion and the tiger, comparable to S. fatalis, and overall somewhat outclassed by S. populator. On a side note, it is interesting to see how robust compared to S. fatalis the modern jaguar is.
The brachial index (radius length/ulna length * 100) of BIOPSI 101 is very low (0.80), indicating that this a closed forest animal. It is for this reason that X. hodsonae was probably more tiger or bear-like than lion-like in its the mass to bone width proportions as widening would be more for muscle foundation than running stress.
Body mass of Xenosmilus hodsonae
With four long bones, we have many different estimators. As Xenosmilus is not a giant as in the likes of the more popular Pleistocene felids, equations can be used but are far from needed.
The humerus is tiger-lion sized in length, thus a mass of 200-240 kg can be applied for this measurement alone. The articular length falls in the same tiger-lion mass range. The midshaft diameter is greater proportionately than that of lion and tiger humeri if you consider the Christiansen and Harris (2005) diameters are from the midshaft as well. Based on Christansen's (1999) assertion that the least tranverse diameter of the humeral shaft is "usually located at midshaft in humerus and femur but often more proximally and distally situated in the radius and tibia, respectively," it is probably okay to. I personally feel the least traverse diameter falls a bit south the midshaft. Nonetheless, Christiansen's data is probably midshaft and thus the midshaft would provide a mass range of 240-290 kg. All in all, the humerus indicates a specimen with a mass of ~235 kg assuming built in between the lion and the tiger, and some thing closer to 270 kg assuming a more tiger-like built.
The femur is short. The length based mass would on its own be around 170 kg. However, referring to the figure above about forelimb and hindlimb ratios, we see X. hodsonae had a very posteriorly sloped body mapping, thus estimating mass via femur length of a cat would be inaccurate. The femoral distal width is large for both a tiger and lion, but not exceptional. Thus a mass of 200-290 kg (yes, that's a large range but the two largest cats of today are proportioned quite differently in this regard) could apply for this measurement. The femoral midshaft diameter produces a lesser mass of 200-240 kg. Overall, if we ignore the length measurement, a mass of ~230 kg assuming built in between the lion and the tiger, and some thing closer to 270 kg assuming a more tiger-like built.
Height of Xenosmilus hodsonae
The shoulder height of X. hodsonae can be determined very easily thanks to the mostly complete specimen BIOPSI 101. Adding up the humerus (avg. 360.5 mm length), ulna (avg. 319 mm length), metacarpal III (only left one available, length 97.8 mm), and the scapula height (broken, I estimate it at around 60 mm vertically in standing position) and accounting for the inherent bend of the bone in natural posture, a in flesh shoulder height of 900-1000 mm is probably in okay range. The hip height would be a good 30 mm less than the shoulder height (considering the femur length (avg. 362 mm), tibia length (avg. 284.5 mm), metatarsal IV length (avg. 96.2 mm), and inominate/pelvis vertical posture height (perhaps c. 70 mm).
