Polar Bear vs Utahraptor

[Dakotaraptor]

Utahraptor is based on specimen (from YU and CEU coll) with 565 mm femoral, which is certainly smaller than BYU 15465. The bear is ~2.5 m in length (from tip to tip) and 1.3-1.4 m tall at shoulder. I tried to make average sized male rather than big one. I suspect the silhouette is bulky and therefore makes Polar Bear an small. 

[DinosaurMichael]

My mistake I meant less than 1,100 lbs around the size of a Polar Bear.

Say's so on the OP.

The largest described U. ostrommaysorum specimens are estimated to have reached up to 7 m (23 ft) long and somewhat less than 500 kg (1,100 lb) in weight, comparable to a polar bear in size.

[Runic]

Nov 23, 2013 5:56:20 GMT 5 DinosaurMichael said:

My mistake I meant less than 1,100 lbs around the size of a Polar Bear.

Say's so on the OP.

The largest described U. ostrommaysorum specimens are estimated to have reached up to 7 m (23 ft) long and somewhat less than 500 kg (1,100 lb) in weight, comparable to a polar bear in size.

The day a 23ft utahraptor weighs less than 500kg is the day I become a terrorist.

[creature386]

Nov 23, 2013 5:56:20 GMT 5 DinosaurMichael said:

My mistake I meant less than 1,100 lbs around the size of a Polar Bear.

Say's so on the OP.

The largest described U. ostrommaysorum specimens are estimated to have reached up to 7 m (23 ft) long and somewhat less than 500 kg (1,100 lb) in weight, comparable to a polar bear in size.

When scaling from Deinonychus, I get 1,400 lb, for a 23 ft Utahraptor.

73 kg*3,4^-3*7³?637 kg

73 kg is the weight given for a 3,4 m Deinonychus (which was compared to Utahraptor all the time in the 1. description).

[Infinity Blade]

A 7 meter Utahraptor would certainly win against an average polar bear, I can tell you that much.

[Carcharodon]

Utahraptor takes this, its clearly dimensionally larger and possesses better weapons.

[blaze]

1.3m-1.4m tall at the shoulder is far from average for any extant bear, creature386 has shared a publication with data on a survey of polar bears, the average male was less than a meter at the shoulder and the biggest one was a little above 1.2m, with the exception of one paper in which shoulder height was measured including the length of the paws and an old Russian publication whose details I ignore, I've never seen any survey of brown or polar bears that includes males much taller than 1.2m.

The book "Mammals of the Soviet Union" says that polar bears are 1.3-1.4m at the shoulder and rarely up to 1.5m at the shoulder, with body lengths up to 2.85m and rarely up to 3m but they criticized the common exaggeration of the size of brown bears even in scientific publications and given how they don't cite anything for the claims of the size of the polar bear I think they are being a little hypocrital there, specially when they also point out the practice of measuring the stretched skin of the bear rather than the bear itself.

Probably the only 1.4m bears are those giants over 650kg.

[Fragillimus335]

Feb 14, 2014 3:21:59 GMT 5 blaze said:

1.3m-1.4m tall at the shoulder is far from average for any extant bear, creature386 has shared a publication with data on a survey of polar bears, the average male was less than a meter at the shoulder and the biggest one was a little above 1.2m, with the exception of one paper in which shoulder height was measured including the length of the paws and an old Russian publication whose details I ignore, I've never seen any survey of brown or polar bears that includes males much taller than 1.2m.

The book "Mammals of the Soviet Union" says that polar bears are 1.3-1.4m at the shoulder and rarely up to 1.5m at the shoulder, with body lengths up to 2.85m and rarely up to 3m but they criticized the common exaggeration of the size of brown bears even in scientific publications and given how they don't cite anything for the claims of the size of the polar bear I think they are being a little hypocrital there, specially when they also point out the practice of measuring the stretched skin of the bear rather than the bear itself.

Probably the only 1.4m bears are those giants over 650kg.

Lol, here is a .95 meter SH polar bear and a 6.5m Utahraptor. This is a disturbing mismatch, but I can't get myself to believe that polar bears average less than 1 meter at the shoulder… 1.2 maybe.

[Fragillimus335]

I just found that (S. N. Atkinson, I. Stirling, M. A. Ramsay 1996) found a sample of ~160 mature males had an average body length of 2.35 meters. That corresponds to a shoulder height of around 1.2-1.25 meters.

[Infinity Blade]

Even then, Utahraptor should still be dimensionally larger. Utahraptor definitely takes this.

[blaze]

Fragillimus335

Depends on the population, what includes in the averages and and how it was measured, the paper you mentioned is it "Growth in early life and relative body size among adult polar bears (Ursus maritimus)" ? because the abstract says the data used was only of 30 mature adult males from the Hudson Bay, Atkinson's thesis also mentions a sample size of only 30 adult mature males (older than 8 years) for the average of 2.35m body length, this corresponds with what Derocher and Stirling (1988) found the greatest asymptotic male body length (maximum size normally reached by full grown adults in a population... more or less) of 2.34m in the Hudson Bay too. Funny thing, the paper that I mentioned (actually a thesis, Eckhardt 2000) was also done in the Hudson Bay but it seems his male sample size of 21 only included a single mature male (the 1.21m tall one).

So fully grown mature male polar bears average a bit over 2.3m long and a bit over 1.2m at the shoulder.

[Fragillimus335]

Feb 14, 2014 7:22:07 GMT 5 blaze said:

Fragillimus335

Depends on the population, what includes in the averages and and how it was measured, the paper you mentioned is it "Growth in early life and relative body size among adult polar bears (Ursus maritimus)" ? because the abstract says the data used was only of 30 mature adult males from the Hudson Bay, Atkinson's thesis also mentions a sample size of only 30 adult mature males (older than 8 years) for the average of 2.35m body length, this corresponds with what Derocher and Stirling (1988) found the greatest asymptotic male body length (maximum size normally reached by full grown adults in a population... more or less) of 2.34m in the Hudson Bay too. Funny thing, the paper that I mentioned (actually a thesis, Eckhardt 2000) was also done in the Hudson Bay but it seems his male sample size of 21 only included a single mature male (the 1.21m tall one).

So fully grown mature male polar bears average a bit over 2.3m long and a bit over 1.2m at the shoulder.

Yeah, those numbers seem much more visually "right" to me. That 30 specimen thing is weird, the graph of dimensions lists 151 specimens for males. :/

[fish]

So many size comparisons on this thread and I'm not sure which is right. The most recent one that fragillimimus posted makes the polar bear look like a kitten next to the dinosaur. But if that comparison is correct, or any other one that shows the Utahraptor dwarfing the bear, wouldnt the dino weigh a lot more then "somewhat less then 1100 lbs", as given by the opening description? If utahraptor truly was such weight it would have been a stick figure compared to the bear, and I cannot see a dimensional advantage alone being much help in what would likely be a grappling contest.

[Infinity Blade]

Feb 16, 2014 6:05:11 GMT 5 fish said:

So many size comparisons on this thread and I'm not sure which is right. The most recent one that fragillimimus posted makes the polar bear look like a kitten next to the dinosaur. But if that comparison is correct, or any other one that shows the Utahraptor dwarfing the bear, wouldnt the dino weigh a lot more then "somewhat less then 1100 lbs", as given by the opening description? If utahraptor truly was such weight it would have been a stick figure compared to the bear, and I cannot see a dimensional advantage alone being much help in what would likely be a grappling contest.

Fish, these size comparisons are exactly what I meant by being visually bigger is an advantage.

I wouldn't be surprised if the drom was indeed heavier than 500 kg, but it is indeed possible to be of the same mass, yet also have more volume.

In any case, it doesn't matter who is more robust or not, as a good height and volume advantage nullifies and even overcomes all of the problems with robusticity. A much larger gracile animal (or at least one that looks visually bigger) will dominate over a smaller (or at least visually smaller) robust one. Why do I think that? Just look at it! I'm sorry, but anyone with perception should be able to pick a winner right off the bat.

I apologize if I sound angry and come off as rude.

[Runic]

Feb 16, 2014 6:05:11 GMT 5 fish said:

So many size comparisons on this thread and I'm not sure which is right. The most recent one that fragillimimus posted makes the polar bear look like a kitten next to the dinosaur. But if that comparison is correct, or any other one that shows the Utahraptor dwarfing the bear, wouldnt the dino weigh a lot more then "somewhat less then 1100 lbs", as given by the opening description? If utahraptor truly was such weight it would have been a stick figure compared to the bear, and I cannot see a dimensional advantage alone being much help in what would likely be a grappling contest.

I agree the odds of a drom visually the size of something larger than a rhino weighing "somewhat" less than 1100lbsis beyond absurd. Dromaeosaurs weren't THAT lightly built infact they were the more robust of the families.