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Comparing Cats: A Discussion of Similarities & Differences
Comparing Cats: A Discussion of Similarities & Differences
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Comparing Cats: A Discussion of Similarities & Differences
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Cats perhaps are the most succesful predators. Over the years, they adapted in many ways. I propose to post anything even remotely related to adaptation and evolution in this thread.
Big cat canine average length, credit to reddhole.
BTW, it is not clearly stated that it was measured from the skull or from the gumline.  *This image is copyright of its original author  *This image is copyright of its original author 
These measurements are probably from the canine in the skull. No living animals were measured in this study.
(04-28-2014, 12:12 AM)'GuateGojira' Wrote: These measurements are probably from the canine in the skull. No living animals were measured in this study. The problem is that they haven't set a clear specification even among the scientific community. Even Mazak has mixed up the different measurement from the skull and from the gumline. We all know that the height of crown means the canine length in straight line, but even Mazak put the 74.5mm one and the 90mm one together without any distinction. The 74.5mm one is a wild specimen being measured from the skull, while the 90mm one is a captive specimen being measured from the gumline. http://www.science.smith.edu/msi/pdf/i00...1-0001.pdf
Here is the ratio of the different parts of a big cat canine tooth.
 *This image is copyright of its original author
Two scans (cat skulls) I made when I was in the Staatliches Museum für Naturkunde in Stuttgart:
 *This image is copyright of its original author  *This image is copyright of its original author Here's a photograph of a real skull to practise:  *This image is copyright of its original author
The claws of the cats:
 *This image is copyright of its original author Extreme sizes, the largest and smallest of the cats:  *This image is copyright of its original author (05-03-2014, 10:07 AM)'GuateGojira' Wrote: The claws of the cats: Nice comparison Guate, but i just wonder why the canine table isn't there yet? And stop shunning my request, if you don't have the time to do it, then i will ask someone else to do it. [img]images/smilies/dodgy.gif[/img] (05-03-2014, 10:11 PM)'GrizzlyClaws' Wrote:That is VERY rude. I am not “shunning” your requests, when I say that I don’t have the time is because I DON’T have the time.(05-03-2014, 10:07 AM)'GuateGojira' Wrote: The claws of the cats: The data is already there, why you don't just collect it? There are only 9 specimens (5 in the flesh and 4 skulls). You can make your own table; there is no need of other persons. I thrust that you can do it. [img]images/smilies/wink.gif[/img] (05-04-2014, 09:19 AM)'GuateGojira' Wrote:(05-03-2014, 10:11 PM)'GrizzlyClaws' Wrote:That is VERY rude. I am not “shunning” your requests, when I say that I don’t have the time is because I DON’T have the time.(05-03-2014, 10:07 AM)'GuateGojira' Wrote: The claws of the cats: Sorry for the harsh tone, i just prefer your way of making the data sheet. BTW, if you don't really have any time, then you should tell earlier. 
I know this last post was 2 years ago, but this is an interesting topic. I also know that GuateGojira and GrizzlyClaws are both excellent posters. I'd love to see more.
@tigerluver @peter
Are you guys familiar with the Adam harstone-rose bite force study and the cranial morphology of wild vs captive Felids study? Maybe two of the most comprehensive studies on the subject I have ever seen! I'll post the links and info when I get a chance but definitely go check them out.
Here it is @tigerluver @peter
http://onlinelibrary.wiley.com/doi/10.1002/ar.22518/pdf and here is the wild vs captive study http://journals.plos.org/plosone/article...ne.0113437 Let me know what you guys think and what others think. Basically its what you expect, Tigers have the highest bite force but jaguars lb for lb are the strongest. There is no lion in this study but the person who turned me on to it works for BJWT and they are very, very knowledgeable, they said the tiger had a 951 psi, lion was 691psi, jaguar was 700psi, nile croc was 7,700psi, white shark was 669psi and the pitbull was 235psi.  *This image is copyright of its original author
Some interesting tid bits from the Captive vs Wild Comparison
"Results Analyses of Linear Variables Males and Females are statistically distinct across each of the linear variables (I-XVII), as we hypothesized (H2); males are substantially larger than females in all linear measures (Table 4). However, the sexes do not differ by either of the shape ratios. Those ratios clearly separate lions from tigers as lions have significantly longer rostra and narrower biangular widths – thus supporting H1 as well. Although the upper carnassial (P4) and premolar-molar rows in lions are only slightly longer than those of tigers (35.57 mm vs. 33.79 mm and 68.25 vs. 63.12 respectively), these differences were also highly significant. All of the statistically significant differences including these tooth lengths along with basal skull length (II), two different metrics related to jaw length (V, and X), and the aforementioned mentioned rostral lengths (I and XIV), all relate, essentially, to the lion’s overall longer muzzle while the tiger has a significantly wider rostrum (XV). (Table 4). Hypothesis 3 (H3) is also supported – there are statistically significant differences between captive and wild pantherines. As has been found by many authors previously [1]–[3], [19], [43], [45], [55], [56] zygomatic arch width statistically differentiates captive and wild lions and tigers with captive specimens having significantly wider skulls. This difference is more than a centimeter on average and the 95% confidence intervals do not overlap – thus the widely acknowledged qualitative observation has clear quantitative validity. However, it is not the most statistically significant differentiator of captive and wild animals; both of the measures of mandibular width – bicoronoid and biangular widths – are also more than a centimeter wider in captive animals with even less overlap between the groups (Table 4, Fig. 2). Thus, not only do the zygomatics flare, as has been previously noted, but so too do the mandibles. Captive animals also have significantly longer alveo-orbital distances, but shorter carnassials, and wider rostra and muzzles. (Table 4, Fig. 2). When all of the linear variables are entered into a principal component analysis, the first principal component (accounting for 72.7% of the variation), as expected for unscaled values, is strongly driven by overall size (as indicated by the positive sign of all of the eigenvectors; Table 5) and statistically separates the sample only by sex (and not species or captivity status; Table 4). Although the second and third principal components (accounting for 8.3% and 5.2% of the variation respectively; Table 5) both significantly divide the sample according to species and captivity status (and not sex). PC 2 divides the sample more clearly by species (Fig. 3A) while PC 3 divides the population more clearly by captivity status – especially when one outlier is removed (Fig. 3B). (The removal of this outlier does not affect the statistical significance of the findings.) The subsequent principal components (accounting for slightly more than 10% of the variation) do not differentiate any of the groups with any clear pattern The second principal component of the linear variable PCA is driven, predominantly, by an inverse relationship of the rostral lengths (most substantially the carnassial length and premolar-molar row length) to the skull width variables (most substantially the biangular and zygomatic widths) – as expected for the long muzzles typical of lions relative to the wide skulls more characteristic of tigers. PC 3 is driven most substantially by an inverse relationship between the rhinion to nasion length and the bicoronoid width. Thus, although the minimum convex units (Fig. 3B) visually separate the population according to captivity status, the eigenvectors that drive this axis are somewhat different than the variables that most substantially sort according to captivity status on their own. The fourth principal component, which does not statistically differentiate the sample by any group (Table 4), is driven primarily by an inverse relationship in the rostral and muzzle breadths relative to some of the mandibular metrics. (Table 5)." I found this very interesting as well "The first principal component is driven most substantially by the anterior-most points relative to the position of the points that lie most close to the midline of the skull in the lateral view – i.e., the position of the zygomatics and the post-orbital processes (Fig. 6). Given that this axis divides the population by species, it is not surprising that the variables that emerge describe the relatively longer muzzle of lions relative to tigers. What is somewhat contrary to what we would have predicted both the anterior-most and posterior-most points show an anterior shift from the tiger morphospace (represented in Fig. 6– by the dot) to the lion morphospace (represented by the end of the line emerging from the dot). Thus the longer rostra found in lions is driven not by an elongation of the anterior portion of the skull, but by the relatively posterior position of the zygomatics and orbits. In other words, according to this analysis, tigers do not have relatively shorter snouts, but relatively rostral eyes and cheeks" "The second principal component is driven by a ventral shift in the anterior- and posterior-most points and a dorsal shift in the dorsal-most points (Fig. 7). The lateral-most points are also greatly affected – a finding in accordance with the conclusion that this axis has a strong relationship with captivity status. Some of the other points that shift substantially along this axis relate to the temporalis origin (i.e., points 40–43) especially the location of the antro-superior corner – the most dramatically shifted point other than those of the zygomatic arch. If we take this axis to be most related to captivity status, captive animals have wider skulls that are less domed than their wild counterparts with dramatically differently shaped temporalis origin – suggesting the importance of this masticatory muscle in the overall shape change in this axis."
The Cranial Morphology of Large Wild versus Captive Felids
http://caravel.sc.edu/2014/12/the-crania...ve-felids/ "RESULTS Graphing the PCA showed that species was the first principle component, accounting for 21.28% of the variation, and visibly separating the groups into lions and tigers with almost zero overlap on the x-axis (See Figure 1 & Table 2). The second principle component clearly represented captivity status, accounting for 15.58% of the variance, and separating the wild and captive specimens across the y-axis. The third principle component represented the sex of the individuals, accounting for 7.97% of the variance. Figure 2 shows the second principle component, captivity status, plotted against the third, with females occupying mostly the lower extreme of the y-axis and males occupying the higher extreme. Differences in morphology were evident at each extreme of the x-axis and y-axis of each PCA test (See Fig. 1 & 2). Among some of the differences were the length of the rostrum, mandibular angle, flexion of the mandibular angles relative to the mandibular symphysis, and the width of the skull. Rostral length differed across species, as tigers were shown to have shorter rostra than lions, which is a trait that has been described by Sunquist (2002) and Christiansen (2007). Christiansen also describes increased nasal height in tigers and differentiates between canine heights across lions and tigers. Mandibular angles also varied across the species, as tigers showed mandibles wider at the top (i.e., bi-coronal breadth) and lions showed the widest point at the base of the mandible (i.e., bi-angular breadth). Different skull shapes and differences in width were also observable across captivity status. Mandibular angle and rostrum length varied across lion and tiger individuals (Figure 1). Captive individuals appeared to have flatter heads than the wild specimens against whom they were compared. The width of the skull across specimens was also noticeably different, as captives seemed to have wider skulls than wilds. Within both species, mandibular angle variation was also evident across males and females." DISCUSSION As expected, the first driving factor, PC1 (21.28%) separated the two species, as obvious phenotypic differences exist between tiger and lion individuals (Sunquist and Sunquist 2002). As you move further right on the x-axis of the graph shown on Figure 1, you can see that the frequency of tiger individuals declines and the frequency of lion individuals increase. Unexpectedly, the second most important source of variation (PC2) was most influenced by captive status (15.57%) and not sex (which emerged as the key factor in PC3). This means that, after species, captive status is the most discernable characteristic across this population. Previous studies on both captive tiger and lion individuals have yielded results supporting the idea that captivity status affects morphology. Geordie Duckler attributed malformations in the external occipital region of tiger skulls to phenotypic plasticity, judging that significant differences between the examined captive and wild specimens of the study were due to “reduced jaw activity” (Duckler 1998). A similar observation was made by O’Regan, examining the cranial thickness in captive lion individuals (O’Regan 2005). Differences across species were evident upon examination of the wireframe renderings of the specimens in Morphologika. One difference is a shortened rostrum in the tiger specimens relative to the lion specimens, which is consistent with descriptions of tigers (Sunquist and Sunquist 2002). This is a possible topic for future research. Mandibular angles also varied across the species, as tigers exhibited wider bi-coronal breadths and lions exhibited wider bi-angular breadth. The results of the PCA output are encouraging, demonstrating the ability of statistical analysis to account for observable qualitative differences across specimens. Variation of skull width and in biangular-anterior mandibular angle, or dome shape was observed differences across captivity status. Wild specimens were found to have more robust domes, than captive (Figure 1). Relatedly, captive specimens had greater skull widths relative to length than wild. The third principle component, observed to be sex, accounted for nearly eight percent of the variance across the sample population (7.97%, respectively.) The fact that sex was the third principle component, behind species and captivity status, suggests that it is easier to tell the difference between captive and wild felids than it is to tell the difference between the sexes of the two species. One explanation for this phenomenon is that behavioral differences between sexes that occur in the wild due to hunting do not occur in captivity and therefore do not contribute to sexual dimorphism in captivity. A further question comes up in the analysis of these data: are females and males affected by captivity to different extents? The results of this study supported the captivity status hypothesis and statistically confirmed that observable differences in cranial morphology do exist across species. These results are especially significant because sexual dimorphism is a known characteristic of both lion and tiger species (Naples 2012, Mazaak 2004). Whether the differences that occur are actually due to mechanical diet is a persistent question. The strength of captivity status as a component of difference in the data also opens up a new line of inquiry about sexual dimorphism. There are two questions to consider: How much do the mechanical properties of food really affect felids? In what other ways captivity status affects morphology of captive felids? A study to further investigate captivity’s impact on cranial morphology will include more species of large carnivores as well as a control group. A type of zoo animal such as Zalophus californicus, the California sea lion, with a diet primarily made up of fish in captivity and the wild should therefore exhibit little to no differences in cranial morphology across captivity status if the morphology is mostly influenced by the food’s mechanical properties. If there are differences in morphology across captivity status, regardless of diet, other possible factors contributing to the differences in cranial morphology across captivity statuses may include genetic issues, for example those stemming from inbreeding. If further studies yield similar results to those of this analysis and continue to show a direct relationship between captive diet and changes in cranial morphology of carnivores, these studies could be a possible basis for handlers and animal dietitians to rethink their policies regarding the mechanical diets of captive carnivores. If a mechanical diet that requires further engagement of masticatory muscles, because nutrients alone are insufficient for the proper maturation and health of captive felids, zoos must take proper measures to assure the health of captive specimens." Probably one of the main reasons why tigers are thought to have the strongest bite of big cats is their relatively shorter jaws compared to Lions Statement from Adam Below: Relative to weight, it’s the jaguar. Recent research by Adam Hartstone-Rose and colleagues at the University of South Carolina, who compared the bite forces of nine different cat species, reveals that jaguars have three-quarters the bite force of tigers. However, given that jaguars are considerably smaller (the body mass of the individual in the study was only half that of the tiger), relatively speaking their bite is stronger. “If you had to choose, you’d want to be bitten by a jaguar, not a lion or a tiger. But pound for pound, jaguars pack a stronger punch,” says Adam. “The strength of the jaguar’s bite is due to the arrangement of its jaw muscles, which, relative to weight, are slightly stronger than those of other cats. In addition – also relative to weight – its jaws are slightly shorter, which increases the leverage for biting.” http://www.discoverwildlife.com/animals/...ngest-bite |
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