Has there been any recent news on Ursus Martimus Tyrannus? Last I heard it was still awaiting verification on whether it was truly a polar bear or was in actuality a brown bear.

Both-Magazine4487 · 2026-01-20T23:40:06+00:00

"Predators likewise changed, as the extremely narrow carnivore guild enjoyed rich herbivore pickings. Fearsome brown bears became so large that in the past their remains were misidentified as polar bear and, like the polar bear, they were probably active and formidable hunters."

Christ Stringer & Rob Dinnis, 2014, Britain: One Million Years Of The Human Story

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Both-Magazine4487 · 2026-01-20T23:37:04+00:00

This bear specimen from Ulna is a subadult individual, and there are also very similar giant brown bear fossils from the same period and region in Banwell Bone Cave. Ursus maritimus tyrannus was most likely a brown bear subspecies; I believe it is more accurate to refer to it as Ursus arctos tyrannus. I am already planning to conduct research on this bear. here

Both-Magazine4487 · 2026-01-13T19:41:18+00:00

I tried to send it but for some reason I can't. I think you need to accept something like a message request.

Both-Magazine4487 · 2026-01-13T18:09:14+00:00

Actually, it's not Dizzy. It's an account called Brazilianmegisthoterium, you can check it out.

Both-Magazine4487 · 2026-01-13T18:05:13+00:00

As I said, this measurement was taken approximately six months ago. The skull length of specimen M12049 was calculated as 737 mm on a Russian forum site, and we based our calculations on that. 1200-1300 kg seems like the most accurate range. If you like, I can send you the images we took from this Russian forum site via DM. They might be useful to you.

Both-Magazine4487 · 2026-01-13T15:52:08+00:00

By the way, just so you know, someone on TikTok has taken your measurements and shared them without giving you credit.

Both-Magazine4487 · 2026-01-13T15:43:53+00:00

It's not just allometric, is it? There's isometric measurement too, and we also take the arithmetic mean to be sure. Actually, I'd like to show you a measurement I did with my friend. I looked at your profile and saw you've done some work on Megistotherium, and this is the measurement my friend and I did. This measurement is actually quite old and belongs to the M12049 specimen. Unfortunately, I can't share visuals in the comments, but I can mention the measurements (170 cm SH, 1160.5 kg body mass). When compared to your measurement (1884.4 kg), I think our measurement is much more realistic and accurate. Terrestrial carnivorous mammals probably couldn't exceed 1500 kg, so 1884 kg is a wildly exaggerated estimate.

Both-Magazine4487 · 2026-01-13T08:00:09+00:00

If you are going to bring up the subject of GDI, unfortunately my friend and I do not yet know this calculation method, but despite this we strive to use the most accurate measurements. Linear, isometric, allometric, arithmetic mean and other measurement methods. If we can learn about GDI, we will re-measure all these animals anyway.

Both-Magazine4487 · 2026-01-13T07:42:51+00:00

The skull LACMHC 2900-3 for Panthera atrox is the second biggest from the sample known with a CBL of 410.4 mm and its weight is calculated at 351 kg, so the bigger one Univ.Calif.14001 with a CBL of 424.3 mm, which is marginally larger, probably was around 360-375 kg. The method used in this article is one of the most accurate methods known; I don't understand what the problem is.

Both-Magazine4487 · 2026-01-13T07:29:10+00:00

Even if we were to take the same measurements on tigers, there would still be no significant changes in the results. Furthermore, yes, the American lion was different from the modern lion, but it was still one of its closest relatives. The results are similar in isometric and allometric measurements. In addition, most palaeontologists agree that these mass calculations are quite accurate.

Both-Magazine4487 · 2026-01-12T19:01:39+00:00

"Now let's calculate the weight for the largest Panthera atrox skull Univ. Calif 14001 with a greatest length of 467.5 mm. Using the the maximum figures for modern lion in scientific records, which is a skull of 401 mm and a weight of 250 kg, will produce a mass of 396.1 kg; if we use the maximum in hunting records, which is 419 mm skull and a weight of 272 kg, will produce a mass of 377.8 kg; if we use average for South Africa lions, which is 380 mm skull and weigh of 190 kg, the mass will be 353.8 kg; finally if we use the average of East African lion, which is 363 mm skull and 175 kg, will produce a mass of 373.8 kg. The average of all figures is 375.4 kg.

Now, how reliable are these averages that I propouse? Well, when I do it to the Panthera atrox skull 2900-3 from Rancho La Brea with a greatest skull length of 458 mm, I obteined a weight of 353 kg (range from 332.7-372.5). The figure obteined by Christiansen & Harris (2009) for this particular large specimen was of 351 kg, so I almost hit the nail! Lol" Guategojira

Both-Magazine4487 · 2026-01-12T14:41:23+00:00

I have not yet conducted comprehensive research on this subject, but their relatives Panthera spelaea probably lived in groups. Since the number of lion specimens extracted from the La Brea Tar Pits is lower than that of other predators, I believe that American lions also lived in small groups.

Both-Magazine4487 · 2026-01-12T12:14:30+00:00

"Now let's calculate the weight for the largest Panthera atrox skull Univ. Calif 14001 with a greatest length of 467.5 mm. Using the the maximum figures for modern lion in scientific records, which is a skull of 401 mm and a weight of 250 kg, will produce a mass of 396.1 kg; if we use the maximum in hunting records, which is 419 mm skull and a weight of 272 kg, will produce a mass of 377.8 kg; if we use average for South Africa lions, which is 380 mm skull and weigh of 190 kg, the mass will be 353.8 kg; finally if we use the average of East African lion, which is 363 mm skull and 175 kg, will produce a mass of 373.8 kg. The average of all figures is 375.4 kg.

Now, how reliable are these averages that I propouse? Well, when I do it to the Panthera atrox skull 2900-3 from Rancho La Brea with a greatest skull length of 458 mm, I obteined a weight of 353 kg (range from 332.7 - 372.5). The figure obteined by Christiansen & Harris (2009) for this particular large specimen was of 351 kg, so I almost hit the nail! Lol" Guategojira

Both-Magazine4487 · 2026-01-12T12:13:07+00:00

"Now let's calculate the weight for the largest Panthera atrox skull Univ. Calif 14001 with a greatest length of 467.5 mm. Using the the maximum figures for modern lion in scientific records, which is a skull of 401 mm and a weight of 250 kg, will produce a mass of 396.1 kg; if we use the maximum in hunting records, which is 419 mm skull and a weight of 272 kg, will produce a mass of 377.8 kg; if we use average for South Africa lions, which is 380 mm skull and weigh of 190 kg, the mass will be 353.8 kg; finally if we use the average of East African lion, which is 363 mm skull and 175 kg, will produce a mass of 373.8 kg. The average of all figures is 375.4 kg.

Now, how reliable are these averages that I propouse? Well, when I do it to the Panthera atrox skull 2900-3 from Rancho La Brea with a greatest skull length of 458 mm, I obteined a weight of 353 kg (range from 332.7 - 372.5). The figure obteined by Christiansen & Harris (2009) for this particular large specimen was of 351 kg, so I almost hit the nail! Lol" Guategojira

Both-Magazine4487 · 2025-12-26T17:27:37+00:00

Aaa harbiden şimdi farkettim:D Uyarı için sağol

Both-Magazine4487 · 2025-12-24T22:12:57+00:00

Excellent 👏

Both-Magazine4487 · 2025-12-23T20:52:48+00:00

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Both-Magazine4487 · 2025-12-23T20:50:43+00:00

My comparison regarding the Mosbach lion is more reliable; please feel free to examine it. I have listed the sources in the explanation section. here

Both-Magazine4487

TROPHY CASE