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The "King" of the bears - comparison between the Polar bear and the Brown bear
The "King" of the bears - comparison between the Polar bear and the Brown bear
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The "King" of the bears - comparison between the Polar bear and the Brown bear
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Don't worry Brotherbear, I will put the data.
The only problem is that I only have skulls from brown bears and few data for polar bears. I will put that of Heptner & Sludskii too, it is very informative. [img]images/smilies/smile.gif[/img] 
The short faced bears have the strongest bite, and it seems the giant panda is also considered to be more closely related to the short faced bears.
http://www.bbc.co.uk/nature/15559929 
Would you say that, pound for pound, the brown bear's bite force was moderate; pretty much average among the bears?
I returned to edit and add; the sun bear is also said to have a powerful bite. (11-07-2014, 03:45 PM)'brotherbear' Wrote: Would you say that, pound for pound, the brown bear's bite force was moderate; pretty much average among the bears? I think black bears are pound for pound the weakest, brown bears are more towards moderate, then follow by the polar bears. BTW, those short-muzzled bears might really be pound for pound the strongest ones. 
Bone Clones specimens:
Here are the specimens from Bone Clones, regarded as some of the largest ones. However, we most be very careful, as the figures are in inches and represent approximated figures. I have found this because the size of the skulls from the Xenosmilus hodsonae, Panthera atrox and Panthera zdanskyi did not match (smaller or larger than the real measurements). So, the sizes quoted here most be taken as "approximations" of the real size. Polar bear: 18" Long, 11 3/16" Wide, 8 1/2" High 457 mm long, 284 mm wide and 216 mm high. "Our Polar Bear Skull is a replica of a specimen believed to be the second largest ever found."  *This image is copyright of its original author Source: http://www.boneclones.com/BC-063.htm Kodiak bear: 18 1/4" Long, 10 1/2" Wide, 10" High 463.6 mm long, 267 mm wide and 254 mm high. "This particular skull is a male and, at 28 3/4 is larger than the official record size of 27 5/16. This specimen was from Kodiak Island in Alaska."  *This image is copyright of its original author Source: http://www.boneclones.com/BC-021.htm This Kodiak bear skull is larger than the official record, according with this source, while the Polar bear is skull is the second on record. Did anyone know which is the "official" Kodiak record skull and the first Polar bear record skull? Greetings. [img]images/smilies/smile.gif[/img]
Nice skulls, they are both similar in length while the polar bear skull seems to be quite a bit wider with the more carnivourous teeth and the kodiak has the odd "fin shape" in the back portion.
Are their weights available of both?
The Great Bear Almanac by Gary Brown: Generally, the skulls of bears are massive, typically long, wide across the forehead with prominent eyebrow ridges, a large jawbone hinge, and with heavy jaw muscles and broad nostrils. Combined with dentition, the structure of bear's skulls are very much carnivorous, though with omnivore modifications.
The skull may be the most important feature of an animal, housing the brain, providing a major protective and nutritional feature ( mouth and teeth ), and containing sensory/communication features. "Bear skulls undergo a series of changes from early life to old age, and in most species do not attain their mature form until seven or more years of age," observed C.H. Merriam in North American Fauna, Biological Survey, 1918. Diet and other eating habits have influenced the individual development of the heads and skulls of each species. "Head shape and size... are influenced by dentition and jaw muscles," write Paul Shepard and Barry Sanders in The Sacred Paw... ( skulls ) are shaped to anchor the approriate muscles. Because of the heavy jaw muscles it ( spectacled bear ) uses for crushing palm nuts, its skull shape is unusual, rather resembling that of the giant panda, which has massive molars for grinding bamboo shoots." Brown bears normally do not bite to kill, but have grinding, crunching teeth with the massive muscles to accomplish the task. Polar bears are more carnivorous than other bears, and do bite to kill; their skulls are specifically shaped for the appropriate teeth and muscles to hold, chop, and slash their prey. Each of the eight bear species has its own distinctive skull shape and size. Spectacled Bear - Wide; short muzzle; lower jaw shorter than upper ( overbite ); unusual skull shape; resembles giant panda; young and female skulls narrow and long. Giant Panda - Massive; wide; zygomatic arches widely spread; constructed for attachment of powerful jaw muscles; short muzzle. Sun Bear - Wide and flat ( unbearlike ); short muzzle. Sloth Bear - Thick; long muzzle; small jaws; bulbous snout; wide nostrils. Asiatic Black Bear - Large; sloping forehead. American Black Bear - Broad, narrow muzzle; large jaw hinge; female head may be more slender and pointed. Brown Bear - Massive; heavily constructed; large in proportion to body; high forehead ( steeply rising ); concave ( dished face ); domed head; long muzzle; flat nose tip; ears barely observed as bumps; eyes tiny. Polar Bear - Large; small in proportion to body; long; snout long ( warms air ); Roman nose; large eyes.
The Great Bear Almanac by Gary Brown - Comparitive Sizes of Skulls - The Boone and Crockett system described in Chapter 6 scores a skull by the total of the length and the width, and ranks the bears accordingly. This is a tangible means of size comparison, but not totally indicative of total size, as individual variations occur. For example, a large, heavy bear may have a small, short, or narrow skull, providing it with a total skull size unrepresentative of its overall body size.
(11-11-2014, 11:44 PM)'Pckts' Wrote: Nice skulls, they are both similar in length while the polar bear skull seems to be quite a bit wider with the more carnivourous teeth and the kodiak has the odd "fin shape" in the back portion.No, there are no weights available. In fact, although there would be weights, we most remember that those are just casts and apparently they don't keep the weights of the original specimens. [img]images/smilies/sad.gif[/img]
Do we have any idea the purpose of the "fin shape" at the back of the Brown bear skull?
It seems that the brown bears skull grow taller while the Polar bears skull grew wider. At least based off these two scans. But its hardly enough for a rule, which I get. 
I am not a bear expert by any means, but I found this on bite force:
 *This image is copyright of its original author Often times depth in a bone, in this case the "fin shape" being referred too, is correlated with increased muscle attachment. The deeper ridge of the brown bear might be part of the muscular reason why it has a proportionately greater bite force. Nice observation.
The Great Bear Almanac by Gary Brown - Shoulder Hump ( brown bear )... Brown bears have a hump between their shoulders that is covered with long hair and is normally a reliable means of species identification. The long hair often accentuates the hump when the "hackles" are raised. This distinguishing feature is a distinctive mass of muscle that provides the brown bears with their exceptional digging ability and the powerful striking force of the forepaws.
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