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Freak Specimens
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 (06-20-2014, 09:52 PM)'tigerluver' Wrote:(06-20-2014, 12:53 PM)'Apollo' Wrote: My doubt is eventhough these cats are similar in dimensions, the Ngandong tiger seems to outweigh all of them by a big margin. So as per dense bones theory, tigers seems to have denser bones than lions. What could be a possible reason for tigers to have denser bones and relatively thinner bones compared to lions ? When it comes to P.atrox and Ngandong, they seems to have similar body dimensions and P.atrox seems capable of reaching bigger dimensions than Ngandon tiger (headbody length and shoulder height). But when comparing weights the P.atrox averages 250Kg and Ngandong tiger weighs (370-415Kg). So the differences is more than 100 Kgs, which confuses me. How come one cat species can weigh more than another cat species by 100kgs when its body dimensions are slightly smaller or similar. Im not getting it. (06-20-2014, 09:58 PM)'tigerluver' Wrote:(06-20-2014, 07:27 PM)'GrizzlyClaws' Wrote:(06-20-2014, 01:01 PM)'Apollo' Wrote: @GrizzlyClaws TFS the pdf file.  (06-22-2014, 10:01 AM)Apollo Wrote:(06-20-2014, 07:23 PM)'GrizzlyClaws' Wrote:(06-20-2014, 12:53 PM)'Apollo' Wrote: @Guate Actually the largest specimen for P. atrox is 351 kg based on a skull. P. atrox may have had proportionately larger skulls as well. No fossil specimens from this species on record has the dimensions that a tiger with a femur of 480 mm would have. A couple of P. s. fossilis specimens on record (a 465 mm ulna and 484.7 mm skull) probably had similar dimensions to the largest Ngandong tiger. I think my equations estimated it around 386 kg.
Dug up an old post I wrote from yuku, I haven't worked with cave lion data in a while.
"tigerluver wrote: The Skull This post will shortly discuss the theoretical mass tied with the large skull (GSL = 484.7 mm, theoretical CBL = 433 mm). The Mazak et al. (2011) gave an estimate of 445 kg, and also seems to overestimate mass. The reasoning behind this is explained in Christiansen and Harris (2005), as follows: "A data sample with many small species would introduce a size-related bias, producing unreliably high body mass estimates for large species." Mazak et al. used the average body mass and condylobasal lengths of each specie as the database to derive the equation. Thus, from the sample size of 6 data points (n=6), 4 were representative of relatively smaller species (P. pardus, N. nebulosa, P. onca, and P. uncia) while 2 were representative of the large species (P. leo and P. tigris). Graphically, there was an uneven distribution of data points, with the smaller species being represent on one extreme and the large on another. Therefore, the data sample had too many small species relative to the amount of large species represented, and thus there was, "a size-related bias, producing unreliably high body mass estimates for large species" (Christiansen and Harris, 2005). Mazak et al. (2011) used a species averaged database to prevent confusion between intra- and inter-specific allometry. Though, in reducing the sample size, the distribution of data became uneven, causing the size-related bias mention above. I constructed a logarithmically scaled graph using the same database of specimens from Mazak et al. (2011), but had each individual specimen to represent a data point rather than a specie average representing a data point. This produced a plot with an even distribution of data points. The resulting equation: log(body mass in kg) = 2.6725*log(condylobasal length in mm) - 4.4587 An implication of this equation is that skull size grows more rapidly than body mass. Furthermore, the data sample used can be more safely applied to P. spelaea as P. spelaea is a distinct species, rather than a subspecie of anomalous species in terms of relative proportions and body mass (e.g. P. t. soloensis to P. tigris), and thus one can assume P. spelaea follows the growth trend of Panthera in general. I realize the wording in this paragraph may be a bit confusing, so just ask if any further clarification is needed on the point I am making. Finally, the equation discussed yields a theoretical body mass for the 484.7 mm skull of approximately 387 kg. The Femur The femur estimate you got is similar to the one I have found with regression. I assumed that P. spelaea had a build midway between tigers and lions and thus based the regression off a database of only tigers and lions. The database for the formula is based off of 6 specimens, the equation: log(mass) = 3.6775*log(femur length) - 7.2568 The 470 mm femur would have a mass of 371 kg accordingly. The Ulna Finally, I will go over the ulna in this short post. As I stated before, an ulna of 465 mm is certainly from a record breaking specimen. To predict the body mass without encounter false negative allometry, I again used a database of tigers and lions, with six specimens in total. The equation: log(mass) = 2.8965*log(ulna length) - 5.1318 The R-squared value was .9, weaker than my other equations. This is because the tiger and lions are significantly different in ulna to body mass proportions, with the former being relatively heavier. Again, I assumed P. spelaea fossilis had a built between the tiger and the lion. The resulting estimate, 393 kg. Putting the ulna into perspective with the Ngandong tiger femur, this specimen probably had a femur of 480 mm as well, give or take. Its mass would be slightly less than the Ngandong specimen (as this specimen is classed as a member of the tiger species, c. 409 kg) again assuming it was not built like a tiger, rather midway between lions and tigers. I am looking into evidence to help figure the built of P. spelaea. Two things support it being very lion-like in built, if not synonymous, genetic data and robusticity of the bones, which fall into the range of modern lions. Furthermore, it is likely P. spelaea was morphologically lion-like as both species lived in similar, open landscapes, calling for greater cursoriality, explaining the relatively great width of the long bones. end post" 
I think, these information about prehistoric cats should be discussed in Extinct Animals sections. This thread is for modern freak specimens. I want that some of you can start this discussion on the Extinct Animals section.
 (06-22-2014, 11:02 AM)'sanjay' Wrote: I think, these information about prehistoric cats should be discussed in Extinct Animals sections. This thread is for modern freak specimens. I want that some of you can start this discussion on the Extinct Animals section. Agree, but our discussion now has involved with the overlap of the modern freak specimen such as Baikal. This guy is almost physically identical to the largest fossil tiger specimen discovered so far.
GrizzlyClaws, I agree about Baikal compared to prehistoric cats.
You can continue to discuss and comparing here. I wanted only that any information related to prehistoric cats should be in that section. Anyway. I thank tigerluver for starting new thread. Hope to see some good data and information about prehistoric cats. (06-22-2014, 10:20 AM)'tigerluver' Wrote:(06-22-2014, 10:01 AM)'Apollo' Wrote:(06-20-2014, 07:23 PM)'GrizzlyClaws' Wrote:(06-20-2014, 12:53 PM)'Apollo' Wrote: @Guate Thanks for the info.
Huge male tiger from Harbin
Here is the video Here are some screen shots taken by P.tigris  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author  *This image is copyright of its original author
More Harbin Monsters in their summer coats
 *This image is copyright of its original author  *This image is copyright of its original author
 (06-24-2014, 12:49 AM)'Pckts' Wrote: More Harbin Monsters in their summer coats First thing, that popped into my eyes: maaaaaassive skull from the tiger in the middle! Here you can clearly notice the difference between a lion and tiger skull. And yes, the forequarters are striking as well. TFS!  *This image is copyright of its original author  *This image is copyright of its original author |
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