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Post by brobear on Oct 9, 2018 5:23:32 GMT -5
Do bears have stronger bones than the big cats. This was once a hot topic with heated debates. I am seeking information here - not opinions. www.lairweb.org.nz/tiger/conflict13.html Almost all queries received on this topic request answers to the lion versus tiger question. Oddly, few people simply ask which is considered the Ultimate Carnivore. This honour is held by an animal the tiger does not often have encounter; it is the grizzly bear. The grizzly bear is a poor predator, taking down a caribou only when the opportunity arises. This, however, shifted his evolution in favour of the job in hand, namely as a digger of hard barren ground for roots, tubers and den building. The grizzly bear subsequently evolved enormous bone and muscle density; roughly ten times our own for a given size. They have developed into huge and enormously powerful animals. Big cat biology is very different. They have evolved powerful elastic muscles over a low weight, low density bone structure to suit their purpose of chasing down prey.
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Post by brobear on Oct 9, 2018 5:45:07 GMT -5
This is what I know about bone density. People who live in the mountains have stronger bones than those who live on the flatlands. Lust like muscle tissue, bones develop strength according to usage. shaggygod.proboards.com/ (Specimen Review) NMNH 123386 (Ursus arctos) NMNH 275124 (Ursus maritimus ) Details on the brown bear is limited. NMNH data tells us it was an adult male bear weighing 330 lbs, while the polar bear was female. Compare the brown bear specimen with the following NMNH 301690 Yellowstone National Park (YNP) grizzly bear sow which weighed 500 lbs. It appears we are looking at a young adult boar. For follow up morphological data on interior and arctic North American brown bears, please visit the URSUS ARCTOS HORRIBILIS & BROWN BEAR section under the North America menu in the EXTANT BEAR PROFILES (IN DEPTH) section. RE: polar bear and brown bear, remember, the polar bear (whose diet is 90% meat) grow larger. Only mature specimens from the largest of brown bear populations where meat input is historically high are comparable to them as it relates to size. Ignoring the equation/formula used to estimate bone density, instead, take a deeper look at the other terrestrial and aquatic specimen values for example the Indian rhino, African lion, and walrus. If you are really interested in this material, go ahead and look up additional specimen info used in this study and share your results. So what do we need to know about the article? Well, W.P. Hall (the article author) thesis contends/states, "Increased bone density is highly correlated with aquatic habits in mammals." According, to Hall, aquatic wildlife that live in a submerged existence produce the highest bone density values when compared to their terrestrial counterparts. An interesting argument, although the specimen material examination (at a quick glance) leaves a lot more to be desired. To tie it in with the brown bear and the polar bear; the brown bear is often foraging for food (a lot of digging, moving stones/boulders, or den construction) while the more maritime polar bear (besides swimming) hunts seal primarily by breaking/puncturing thick ice. In short, there is a lot of dynamic forelimb activity coupled with large active hunting territory (see both hind-limbs and forelimb activities). IMO, corresponding bone density values plus quantitative sampling visa vi mature/prime male polar bears or boar brown bears (regardless of population) would be very interesting to look at.
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Post by brobear on Oct 9, 2018 5:48:26 GMT -5
Grrraaahhh... Post by grrraaahhh on Oct 18, 2011 at 11:17am In case other members are not aware, the OP was citing the following article: Hall, P. William. The Correlation between High Limb-Bone Density and Aquatic Habits in Recent Mammals (1983). J. Paleont. 2:197-207. UrsusMaritimus... The information talks about the bone density that semi aquatic animals genrally have higher bone density compared to fully terrestrial animals. In conclusion, the polar bear being a semi-aquatic animal has denser bones than the brown bear. I am not sure wheather higer bone density equals more muscle mass. Some might say so others will disagree. Note: This is an assumption as the post above explains. It is aquatic lifestyle vs heavy work lifestyle. Unresolved.
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Post by brobear on Oct 9, 2018 6:27:53 GMT -5
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Post by Deleted on Oct 10, 2018 0:39:34 GMT -5
Do bears have stronger bones than the big cats. This was once a hot topic with heated debates. I am seeking information here - not opinions. www.lairweb.org.nz/tiger/conflict13.html Almost all queries received on this topic request answers to the lion versus tiger question. Oddly, few people simply ask which is considered the Ultimate Carnivore. This honour is held by an animal the tiger does not often have encounter; it is the grizzly bear. The grizzly bear is a poor predator, taking down a caribou only when the opportunity arises. This, however, shifted his evolution in favour of the job in hand, namely as a digger of hard barren ground for roots, tubers and den building. The grizzly bear subsequently evolved enormous bone and muscle density; roughly ten times our own for a given size. They have developed into huge and enormously powerful animals. Big cat biology is very different. They have evolved powerful elastic muscles over a low weight, low density bone structure to suit their purpose of chasing down prey. I agree and I feel that bears would have thicker more robust bones than a big cats because you need strong bones to support all that weight. But I could be wrong.
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Post by brobear on Oct 25, 2018 15:46:08 GMT -5
In a contest between a grizzly and a big cat, which should have the stronger bones? I remember this debate from way-back-when on AVA. Bone density has more to do with bone usage than by species. For most of his day, an Amur tiger is walking. Bengal tigers spend less time walking. Lions might spend 20 hours a day sleeping. Among these biggest of the big cats, the Amur should have the denser bones. A grizzly, more than any other bear, spends long hours digging in hard ground, over-turning rocks and logs, tearing into dead trees in search of honey, or ripping stumps apart in search of grubs and beetles. This bear should have denser bones than any big cat.
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Post by brobear on Mar 8, 2019 5:33:57 GMT -5
Something I noticed over in "Carnivora"... the cat fan-boys are still telling the fable about big cats having stronger bones than bears. Now, I will admit that big cats cannot have weak bones, else when a 450-pound tiger leaps over a 10-foot-high fence, he would break his legs in landing. However, building strong bones comes from two sources; diet and usage ( work ). Polar bears grow strong bones from swimming. A grizzly, more than any other bear, spends long hours digging in hard ground, over-turning rocks and logs, tearing into dead trees in search of honey, or ripping stumps apart in search of grubs and beetles. This bear should have denser bones than any big cat. *Note: I will not be taking this "debate" over to Carnivora. I have no plans of returning to that juvenile delinquent playground.
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Post by BruteStrength on Mar 8, 2019 6:00:11 GMT -5
I agree Carnivora is full of nutjobs. I think bears have denser bones than big cats but I could be wrong.
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Post by Deleted on Mar 27, 2019 7:46:39 GMT -5
Grrraaahhh... Post by grrraaahhh on Oct 18, 2011 at 11:17am In case other members are not aware, the OP was citing the following article: Hall, P. William. The Correlation between High Limb-Bone Density and Aquatic Habits in Recent Mammals (1983). J. Paleont. 2:197-207. UrsusMaritimus... The information talks about the bone density that semi aquatic animals genrally have higher bone density compared to fully terrestrial animals. In conclusion, the polar bear being a semi-aquatic animal has denser bones than the brown bear. I am not sure wheather higer bone density equals more muscle mass. Some might say so others will disagree. Note: This is an assumption as the post above explains. It is aquatic lifestyle vs heavy work lifestyle. Unresolved. Polar bears (Ursus Maritimus), the most evolutionary advanced hibernators, avoid significant bone loss during hibernationwww.researchgate.net/publication/5603402_Polar_bears_Ursus_Maritimus_the_most_evolutionary_advanced_hibernators_avoid_significant_bone_loss_during_hibernation
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Post by King Kodiak on Apr 28, 2019 15:42:40 GMT -5
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Post by brobear on Apr 28, 2019 16:17:10 GMT -5
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Post by King Kodiak on Apr 28, 2019 22:09:31 GMT -5
All that is pretty hard to understand yeah. I think Polar would know.
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Post by Deleted on Apr 29, 2019 6:48:17 GMT -5
Something I noticed over in "Carnivora"... the cat fan-boys are still telling the fable about big cats having stronger bones than bears. Now, I will admit that big cats cannot have weak bones, else when a 450-pound tiger leaps over a 10-foot-high fence, he would break his legs in landing. However, building strong bones comes from two sources; diet and usage ( work ). Polar bears grow strong bones from swimming. A grizzly, more than any other bear, spends long hours digging in hard ground, over-turning rocks and logs, tearing into dead trees in search of honey, or ripping stumps apart in search of grubs and beetles. This bear should have denser bones than any big cat. *Note: I will not be taking this "debate" over to Carnivora. I have no plans of returning to that juvenile delinquent playground. Hey brobear, I got this study from you. But it's credibility was questioned in Carnivora. I'd like to know if you have information about what muscle groups are used and the process.. cloud.tapatalk.com/s/5cc6e4865a082/Muscular%20Structure%20and%20Morphology%20in%20Bears%20-%20Document%20II%20.pdf
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Post by brobear on Apr 29, 2019 17:06:45 GMT -5
In conclusion, no significant evidence provided any leads towards increased muscle strength deterioration or muscle mass deterioration in postprime brown bears, yet evidence had been found of increased muscle volume deterioration in postprime brown bears as. The brown bears who were experimented on were shortly released back into their respective locations within Yellowstone National Park after the study commenced. These findings suggest that brown bears, if not all bear species as a whole, are able to retain their muscle mass and maximum muscle strength well past their prime years, unlike most other animals. Credibility questioned only by those who dislike the truth.
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Post by King Kodiak on Apr 29, 2019 18:14:39 GMT -5
I dont see whats wrong with that study. I mean just take a look at the authors. Does not get any better. The part of this study that the fanboys dont like its on red, lmao.
These findings suggest that brown bears, if not all bear species as a whole, are able to retain their muscle mass and maximum muscle strength well past their prime years, unlike most other animals.
Pretty serious authors here:
Credits to: Dr. MartinAndrews (head of this study, and professor at Michigan State University.) Matt Powers (alumni from MSU in 1997, master’s degree in zoology and bachelor’s degree in computer data systems.) Travel Rills (student at MSU, bachelor's degree in zoology.) Mary Gillesy (student at MSU, bachelor's degree in zoology.) Adam Leesok (student at MSU, associate’s degree in computer systems engineering, volunteered for the weighing of bears analyzed.)
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Post by Deleted on Apr 30, 2019 0:25:45 GMT -5
In conclusion, no significant evidence provided any leads towards increased muscle strength deterioration or muscle mass deterioration in postprime brown bears, yet evidence had been found of increased muscle volume deterioration in postprime brown bears as. The brown bears who were experimented on were shortly released back into their respective locations within Yellowstone National Park after the study commenced. These findings suggest that brown bears, if not all bear species as a whole, are able to retain their muscle mass and maximum muscle strength well past their prime years, unlike most other animals. Credibility questioned only by those who dislike the truth. Right. I believe in that study. But I'd like to know what muscle groups are used..
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Post by brobear on Apr 30, 2019 1:52:47 GMT -5
This does not mean that brown bears do not reach a certain point where age begins to take its toll. Bears are not immortal. One sign to look for in a brown bear showing old age is in his shoulder hump. This hump of muscles is normally rounded; a round mound of muscle. But as age begins to deteriorate the bear's muscle mass, a deep V can be seen on his shoulder hump. A brown bear is not ravaged by age until well within his 20's. shaggygod.proboards.com/thread/671/grizzly-bear-anatomy?page=1
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Post by King Kodiak on Apr 30, 2019 4:46:30 GMT -5
Bears' Bones Are a Model for Solving Human Osteoporosis Bears may hold the secret to keeping our bones healthy. Researchers struggling with the limitations of current medications for osteoporosis may soon be out of the woods. Michigan Technological University biomedical engineer Seth Donohue has been trying to figure out why the bones of bears stay strong despite several months of hibernation each year. This amount of inactivity for humans would make our bones as frail as pretzel sticks. By studying bear bones, Donohue's work could lead to new treatments for osteoporosis, the loss of bone density that comes with age. It's natural for bone to renew itself constantly — a cycle of bone resorption (decay) and formation. When our bones decay, cells called osteoclasts break down the bone and release the minerals inside. An imbalance in this cycle is the core mechanism for osteoporosis. Most of today's drugs for this disease aim to prevent bone loss. But Donohue argues that it may be more effective to increase bone formation. That's what hibernating black bears do. Donohue reported online in the Journal of Experimental Biology that while they do lose bone during hibernation, black bears grow new bone cells at an equal or faster rate. "And in fact their bending strength increases as a function of age, despite these annual periods of immobilization," Donohue says. Analyzing blood samples from hibernating bears, he reported that levels of a hormone known to promote bone growth, called parathyroid hormone or PTH, actually increase during hibernation. He points to one study in people that found that a synthetic version of PTH increased bone mineral density in postmenopausal women. Donohue says that since the black bear version of the PTH gene is different from humans, understanding how it works could lead to better ways to treat or prevent osteoporosis in people. "We could develop those hormones or other growth factors synthetically, and then this could be used for drug treatments for osteoporosis in humans," he says. Donahue has synthesized the hormone in his lab and his next step is to sprinkle it on bone cells and watch for bone-forming activity. discovermagazine.com/2006/jun/osteobears
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Post by OldGreenGrolar on Jun 23, 2019 5:30:58 GMT -5
There is some data obtained from another forum: 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: 204 157-169: 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. (To be continued..............)
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Post by OldGreenGrolar on Jun 23, 2019 5:33:36 GMT -5
(From the post above............) 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. (to be continued...................)
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