Post by LeopJag on Mar 15, 2012 0:13:48 GMT -5
Originally posted by Reddhole
Summary
The following study details carnivore limb bone lengths and widths, which we can use to infer both limb and overall body robusticity.
Source: Bertram and Biewner, "Differential Scaling of Limb Bones in Terrestrial Carnivores and Other Mammalia", Journal of Morphology: 204:P 157-169: 1990
For years posters have debated the overall strength of individual species. Commonly people post pictures of individual animals that purport to show that one species is stronger than another. Unfortunately, these picture comparison are unscientific in that the individual animals could have thick fur, the pictures can be taken at flattering or unflattering angles, or the photos may be photoshopped.
A more scientific approach involves limb bone dimensions. Scientists have found that limb lengths and widths (especially humerus or upper arm bone and femur or upper leg bone) correlatate strongly with body mass. Of the two, limb bone width is generally the better measure because wider bones can support more body mass. Thus, an animal with relatively wider bones is usually a stockier and therefore more powerful animal (although individual muscles may not be).
This study details humerus, femur, radius (forearm bone), and tibia (lower leg bone) lengths and two measures of width - anterioposterior diameter (AP diameter) and mediolateral diameter (ML diameter). Another study in which Ursus and I have posted extracts before found that animals that run fast (cursors and ambushers to a lesser extent) tend to have relatively wide AP diameters in their limb bones compared to animals that run at lower speeds or less often (i.e bears, mustelids, etc.). Here is the relavant extract:
For example, the cheetah has relatively robust limbs if we use AP diameter, but rather gracile limbs if we use ML diameter. As a result, I think ML diameter is the better measure because it leaves out limb bone thickening due to high speed running.
The humerus and radius robustness measures are also interesting from a grappling perspective. Animals that grapple with heavy prey tend to develop a relatively more robust humerus and radius to handle the high stresses involved in handling large prey. In fact humerus and radius robustness were two key morphological traits of cats that kill large vs,. small prey in the feline grappling study I posted a few months back.
The study used several mature adult specimens with roughly equal numbers of each sex when possible. I do not think sexual dimorphism should play much of a role since another study of feline limb bone dimensions did not show much change in relatively limb robusticity between sexes of each species.
Another thing to note is that animal limb bones become slightly more robust as they get larger all else being equal. The trend is not too significant until animals reach about 100-300 KG.
Below is the raw data. Also, note we can calculate radius/humerus and tibia/femur (i.e. mechanical advantage of the forearm and lower leg - lower values mean stronger forearms and more stable rear legs all else being equal) from this data.
Here are some general observations - mostly based off of ML diameter of the humerus (i.e. ML diameter of humerus/humerus length) unless otherwise noted.
1) The maned wolf is an extremely gracile animal as most folks already know. It has the most slender humerus ,5.75%, of any cat or dog (see below) and likely any other carnivore.
2) All of the badgers, including the wolverine, are extremely robust. Some of these measurements are as follows:
Honey Badger: 8.9%
Wolverine: 8.4%
American Badger: 10.56%
Eurasian badger: 10.04%
3) The bears are extremely robust, even the smaller species, which should not have extreme thickening of the limb bones that larger species do. Most have humerus's as or more robust (based off of ML diameter) than any big cat.
Sun Bear: 9.6%
Sloth Bear: 11.67%
Black Bear: 9.7%
Giant Panda 9.7%
4) Lion Vs. Tiger
The lion has a more robust humerus and femur based on both ML and AP diameter
Lion: 8.92%; 12.78%
Tiger: 8.57%; 11.37%
The lion has a more robust radius and tibia based off of ML diameter while the tiger's radius and tibia is more robust based off of AP diameter.
As most already know, the tiger has the lower (i.e. more advantageous) radius/humerus and tibia/femur ratios.
4) The spotted hyena has very robust limbs - 9.3% humerus ML diameter and 12.94% AP diameter. The only cats that exceed it in ML diameter robusticity are the jaguar and cougar (only slightly). The spotted hyena's AP diameter robusticity is greater than any big cat. Given this data and some skull size data I've seen, I think I now favor the spotted hyena over both a male leopard and the gray wolf - although I have to admit some of its real-life performance (i.e. killing methods, lack of lethal aggression towards many other predators) is not too impressive.
5) The bush dog is extremely robust with a humerus ML diameter robusticity of 9.18%. The only cats that exceed it are the cougar and jaguar.
6) Most small cats are not small versions of big cats. Over the years, many people have argued that most small cats are significantly different than big cats. Small cats often need slender bones to reduce weight and enhance agility in killing small prey. As a result, they trade off a significant amount of grappling ability. The following tables show all of the felid and canid species ranked by humerus ML diameter robusticity, AP diameter robusticity, and total humerus robusticity (AP diameter + ML diameter/humerus length). As mentioned before, I think ML diameter is the most relevant measure since some high speed runners, i.e. the cheetah, may have inflated AP diameter to withstand the stress from high speed running.
A clear example of the difference between big cat vs. canid and small cat vs. canid is the comparison of the cougar and gray wolf vs. the coyote and eurasian lynx and caracal. The cougar's humerus ML diameter robusticity is 9.39% and the gray wolf's is 7.85%. This indicates that the cougar is a significantly more robust animal, and can overpower a wolf when grappling and kill the wolf. The case with the coyote and the eurasian lynx and caracal is completely different with the corresponding robusticity figures below:
Eurasian Lynx: 6.67%
Caracal: 7.55%
Coyote: 8.05%
Given this data, I have a hard time believing the either of these cats will overpower the coyote and restrain it to make a killing bite. Cats require a good degree of control to kill opponents with their precise and deadly killing bite. As such, IMHO a cat species must be a good deal stronger than its opponent to win (with certain exceptions being extremely slow animals). There are quite a few cat species that have less robust humerus's than canid species, even at the same body size.
The two small cat species with impressive humerus robusticity are the ocelot and the fishing cat - both of which are forest species.
7) The clouded leopard is extremely impressive grouping in the middle of the big cats. As a comparison, the CL's humerus ML diameter robusticity is 9.01% while the Eurasian Lynx is 6.67% and the wolverine's is 8.4%.
_______________
By Reddhole -
Here is a comparison of two extinct sabertooths - the nimravid, Barbourofelis Loveorum (much smaller than a likely less robust than Barbourfelis Fricki) and the feline, Nimravides Galiani.
Barbourofelis Loverum AP diameter robusticity is:
13.94% (37.7/270.5)
Nimravides Galliani's AP diameter robusticity is:
14.6%
This compares with some extant species:
Ursus Arctos: 11.8%
Panthera Leo: 12.78%
Panthera Tigris: 11.37%
Panthera Onca: 12.8%
Nimravides may have been more cursorial than Barbourofelis Loverum and higher speed running may have led to a thickening AP diameter. Unfortunately, ML diameter is unavailable. However, the transverse diameter's at midshaft are about equal and the ends ("proximal" and "distal" "width" and "diameter") of the humerus are more robust for Barbourofelis.
Barbourofelis also has a relatively more robust ulna than Nimaravides based on numerous width/diameter measures divided by ulna length.
Barbourofelis also has a much more robust radius than Nimarvides based on numerous width and diameter measures divided by radius length. Unfortunately, we can't compare these with extant species as AP and ML diameters at midshaft were not measured. However, both species have low radius/humerus ratios with Barbourofelis having a remarkable figure:
Nimravides: 81.2%
Barbourofelis Loverun: 69.1%
This compares with some extant species:
Ursus Arctos: 75.7%
Panthera Leo: 90.1%
Panthera Tigris: 80.6%
Panthera Onca: 78.5%
Summary
The following study details carnivore limb bone lengths and widths, which we can use to infer both limb and overall body robusticity.
Source: Bertram and Biewner, "Differential Scaling of Limb Bones in Terrestrial Carnivores and Other Mammalia", Journal of Morphology: 204:P 157-169: 1990
For years posters have debated the overall strength of individual species. Commonly people post pictures of individual animals that purport to show that one species is stronger than another. Unfortunately, these picture comparison are unscientific in that the individual animals could have thick fur, the pictures can be taken at flattering or unflattering angles, or the photos may be photoshopped.
A more scientific approach involves limb bone dimensions. Scientists have found that limb lengths and widths (especially humerus or upper arm bone and femur or upper leg bone) correlatate strongly with body mass. Of the two, limb bone width is generally the better measure because wider bones can support more body mass. Thus, an animal with relatively wider bones is usually a stockier and therefore more powerful animal (although individual muscles may not be).
This study details humerus, femur, radius (forearm bone), and tibia (lower leg bone) lengths and two measures of width - anterioposterior diameter (AP diameter) and mediolateral diameter (ML diameter). Another study in which Ursus and I have posted extracts before found that animals that run fast (cursors and ambushers to a lesser extent) tend to have relatively wide AP diameters in their limb bones compared to animals that run at lower speeds or less often (i.e bears, mustelids, etc.). Here is the relavant extract:
For example, the cheetah has relatively robust limbs if we use AP diameter, but rather gracile limbs if we use ML diameter. As a result, I think ML diameter is the better measure because it leaves out limb bone thickening due to high speed running.
The humerus and radius robustness measures are also interesting from a grappling perspective. Animals that grapple with heavy prey tend to develop a relatively more robust humerus and radius to handle the high stresses involved in handling large prey. In fact humerus and radius robustness were two key morphological traits of cats that kill large vs,. small prey in the feline grappling study I posted a few months back.
The study used several mature adult specimens with roughly equal numbers of each sex when possible. I do not think sexual dimorphism should play much of a role since another study of feline limb bone dimensions did not show much change in relatively limb robusticity between sexes of each species.
Another thing to note is that animal limb bones become slightly more robust as they get larger all else being equal. The trend is not too significant until animals reach about 100-300 KG.
Below is the raw data. Also, note we can calculate radius/humerus and tibia/femur (i.e. mechanical advantage of the forearm and lower leg - lower values mean stronger forearms and more stable rear legs all else being equal) from this data.
Here are some general observations - mostly based off of ML diameter of the humerus (i.e. ML diameter of humerus/humerus length) unless otherwise noted.
1) The maned wolf is an extremely gracile animal as most folks already know. It has the most slender humerus ,5.75%, of any cat or dog (see below) and likely any other carnivore.
2) All of the badgers, including the wolverine, are extremely robust. Some of these measurements are as follows:
Honey Badger: 8.9%
Wolverine: 8.4%
American Badger: 10.56%
Eurasian badger: 10.04%
3) The bears are extremely robust, even the smaller species, which should not have extreme thickening of the limb bones that larger species do. Most have humerus's as or more robust (based off of ML diameter) than any big cat.
Sun Bear: 9.6%
Sloth Bear: 11.67%
Black Bear: 9.7%
Giant Panda 9.7%
4) Lion Vs. Tiger
The lion has a more robust humerus and femur based on both ML and AP diameter
Lion: 8.92%; 12.78%
Tiger: 8.57%; 11.37%
The lion has a more robust radius and tibia based off of ML diameter while the tiger's radius and tibia is more robust based off of AP diameter.
As most already know, the tiger has the lower (i.e. more advantageous) radius/humerus and tibia/femur ratios.
4) The spotted hyena has very robust limbs - 9.3% humerus ML diameter and 12.94% AP diameter. The only cats that exceed it in ML diameter robusticity are the jaguar and cougar (only slightly). The spotted hyena's AP diameter robusticity is greater than any big cat. Given this data and some skull size data I've seen, I think I now favor the spotted hyena over both a male leopard and the gray wolf - although I have to admit some of its real-life performance (i.e. killing methods, lack of lethal aggression towards many other predators) is not too impressive.
5) The bush dog is extremely robust with a humerus ML diameter robusticity of 9.18%. The only cats that exceed it are the cougar and jaguar.
6) Most small cats are not small versions of big cats. Over the years, many people have argued that most small cats are significantly different than big cats. Small cats often need slender bones to reduce weight and enhance agility in killing small prey. As a result, they trade off a significant amount of grappling ability. The following tables show all of the felid and canid species ranked by humerus ML diameter robusticity, AP diameter robusticity, and total humerus robusticity (AP diameter + ML diameter/humerus length). As mentioned before, I think ML diameter is the most relevant measure since some high speed runners, i.e. the cheetah, may have inflated AP diameter to withstand the stress from high speed running.
A clear example of the difference between big cat vs. canid and small cat vs. canid is the comparison of the cougar and gray wolf vs. the coyote and eurasian lynx and caracal. The cougar's humerus ML diameter robusticity is 9.39% and the gray wolf's is 7.85%. This indicates that the cougar is a significantly more robust animal, and can overpower a wolf when grappling and kill the wolf. The case with the coyote and the eurasian lynx and caracal is completely different with the corresponding robusticity figures below:
Eurasian Lynx: 6.67%
Caracal: 7.55%
Coyote: 8.05%
Given this data, I have a hard time believing the either of these cats will overpower the coyote and restrain it to make a killing bite. Cats require a good degree of control to kill opponents with their precise and deadly killing bite. As such, IMHO a cat species must be a good deal stronger than its opponent to win (with certain exceptions being extremely slow animals). There are quite a few cat species that have less robust humerus's than canid species, even at the same body size.
The two small cat species with impressive humerus robusticity are the ocelot and the fishing cat - both of which are forest species.
7) The clouded leopard is extremely impressive grouping in the middle of the big cats. As a comparison, the CL's humerus ML diameter robusticity is 9.01% while the Eurasian Lynx is 6.67% and the wolverine's is 8.4%.
_______________
By Reddhole -
Here is a comparison of two extinct sabertooths - the nimravid, Barbourofelis Loveorum (much smaller than a likely less robust than Barbourfelis Fricki) and the feline, Nimravides Galiani.
Barbourofelis Loverum AP diameter robusticity is:
13.94% (37.7/270.5)
Nimravides Galliani's AP diameter robusticity is:
14.6%
This compares with some extant species:
Ursus Arctos: 11.8%
Panthera Leo: 12.78%
Panthera Tigris: 11.37%
Panthera Onca: 12.8%
Nimravides may have been more cursorial than Barbourofelis Loverum and higher speed running may have led to a thickening AP diameter. Unfortunately, ML diameter is unavailable. However, the transverse diameter's at midshaft are about equal and the ends ("proximal" and "distal" "width" and "diameter") of the humerus are more robust for Barbourofelis.
Barbourofelis also has a relatively more robust ulna than Nimaravides based on numerous width/diameter measures divided by ulna length.
Barbourofelis also has a much more robust radius than Nimarvides based on numerous width and diameter measures divided by radius length. Unfortunately, we can't compare these with extant species as AP and ML diameters at midshaft were not measured. However, both species have low radius/humerus ratios with Barbourofelis having a remarkable figure:
Nimravides: 81.2%
Barbourofelis Loverun: 69.1%
This compares with some extant species:
Ursus Arctos: 75.7%
Panthera Leo: 90.1%
Panthera Tigris: 80.6%
Panthera Onca: 78.5%
