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Post by brobear on Sept 29, 2020 6:50:42 GMT -5
economictimes.indiatimes.com/news/international/world-news/perfectly-frozen-remains-of-a-39000-year-old-ice-age-bear-found-in-russia/the-discovery/slideshow/78123064.cms Perfectly frozen remains of a 39,000-year-old Ice Age bear found in Russia - Updated: 15 Sep 2020, 02:18 PM. The bear carcass was found by reindeer herders on Bolshoy Lyakhovsky Island. It is the largest of the Lyakhovsky Islands, which are part of the New Siberian Islands archipelago that lies between the Laptev Sea and the East Siberian Sea. Scientists of the North-Eastern Federal University in Yakutsk, the premier center for research into woolly mammoths and other prehistoric species, hailed the find as groundbreaking as previously scientists only had been able to discover the bones of cave bears. This is the first time that scientists have seen such a bear with its teeth and even its nose intact. A preliminary analysis indicated that the adult bear lived 22,000 to 39,500 years ago. A radiocarbon analysis to determine the precise age of the bear, scientists said. The Cave Bears were said to be living in Europe and Asia during the Pleistocene age which is considered to be the period between 2,580,000 to 11,700 years ago. They went extinct about 24,000 years ago (some put it at 15,000 years ago).
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Post by OldGreenGrolar on Oct 1, 2020 9:23:04 GMT -5
I like to see the source which says the cave bear has the heaviest bones out of all bears. It is the bear of all bears.
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Post by brobear on Oct 2, 2020 13:51:31 GMT -5
I like to see the source which says the cave bear has the heaviest bones out of all bears. It is the bear of all bears. One paleontologist described the cave bear ( perfectly ) as being "THE MOST BEARISH of BEARS".  |
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Post by King Kodiak on Oct 2, 2020 14:00:48 GMT -5
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Post by brobear on Nov 1, 2020 18:28:40 GMT -5
blogs.biomedcentral.com/bmcseriesblog/2017/06/07/understanding-brain-size-cave-bears/ Understanding the brain size of cave bears - Kristof Veitschegger 7 Jun 2017 The cave bear became extinct around 24,000 years ago, but its fossils are so abundant that we still have the capacity to study them. In this guest blog, Kristof Veitschegger discusses his research, published this week in BMC Evolutionary Biology, that questions the common perception of cave bears as small brained and 'stupid'. The Pleistocene was a time when giant mammals were common in Europe. One of them was the cave bear. This species is one of the most abundant fossil taxa from Europe due to its strategy of surviving the winter by resting, and consequently sometimes not surviving, in caves. Thus, many fossil remains are perfectly preserved. Most researchers agree that cave bears were predominantly herbivorous and mostly ate soft leaved plants such as herbs. When I started my research on the brain size of cave bears, I was confronted with a short anecdote of the “stupid,” plant eating bear in the cave. The basis for this was the idea of an evolutionary brain size arms-race between predator and prey, where predators needed to always be smarter. Here, it is important to note that overall or relative brain size does not necessarily reflect intelligence. I wanted to look further into this anecdote and see if there is any validity to it. Thus, I started to collect data on dietary preferences of all studied bear species and scored them on a scale where leaf consumption would result in small brains, and animal protein consumption in big brains. Additionally, I also wanted to see if the annual cycle of fattening up for the winter and starving until spring affected the costly brain matter .My research showed that neither diet nor dormancy alone had a significant effect on the relative brain size of cave bears. Thus, the results do not give validity to the anecdote of the “stupid,” plant eating bear. However, there was a weak environmental influence that affected the brain size of cave bears as is shown in the combined score of diet and dormancy. I also wanted to understand the effect that body size had on the brain of cave bears. Cave bears were one of the biggest bear species ever to roam the earth and body mass estimations are between 225 and 1,500 kg. My research showed that the body mass of cave bears increased at a much higher pace than brain mass. Thus, cave bears ended up with small brains compared to their body size. Pictured: Difference in brain volume between polar bear (left) and cave bear (right) (skulls are stored in PIMUZ, Switzerland). Glasses are filled with 6 mm glass beads as representation of the different brain volumes. Kristof Veitschegger 
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Post by brobear on Nov 1, 2020 18:33:26 GMT -5
Quote from reply #4: Cave bears were one of the biggest bear species ever to roam the earth and body mass estimations are between 225 and 1,500 kg.
1500 kilograms is equal to 3,306.93 pounds (avoirdupois)
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Post by OldGreenGrolar on Nov 1, 2020 18:38:00 GMT -5
That is one huge bear. I doubt the cave bears were ‘stupid’ and big males are certainly immune to predation.
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Post by brobear on Nov 1, 2020 18:59:22 GMT -5
That is one huge bear. I doubt the cave bears were ‘stupid’ and big males are certainly immune to predation. Less intelligent than a polar bear, but probably well above most predators.  Cave bear - a little less brain; a little more brawn. Arctos and Spelaeus each have plenty of both. |
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Post by brobear on Nov 1, 2020 19:57:38 GMT -5
Cave Bear credit to @prehistoricage1 ![]()  |
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Post by brobear on Dec 30, 2020 5:31:05 GMT -5
www.sciencedirect.com/science/article/pii/S163106830900133X Bite force of the extinct Pleistocene Cave bear Ursus spelaeus Rosenmüller from Europe. In this paper, I have made a theoretical calculation of the Cave bear's bite force (BF) following the “dry skull method” and I present for the first time BF data that can be of interest to elucidate the mechanisms underlying the dietary choice of the Cave bears. In the skulls studied, males show higher BF than females in absolute terms, but more similar with regard to their body mass, which partly compensates for the smaller size of the females. The whole sample studied shows lower BF in the upper carnassial than those of large cats, similar to the one calculated for the Giant panda and higher than that of Polar bear.
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Post by brobear on Feb 21, 2021 4:23:35 GMT -5
wildfact.com/forum/topic-bears-of-the-pleistocene?pid=139594#pid139594 Middle Pleistocene genome calibrates a revised evolutionary history of extinct cave bears Summary: Palaeogenomes provide the potential to study evolutionary processes in real time, but this potential is limited by our ability to recover genetic data over extended timescales.1 As a consequence, most studies so far have focused on samples of Late Pleistocene or Holocene age, which covers only a small part of the history of many clades and species. Here, we report the recovery of a low coverage palaeogenome from the petrous bone of a ∼360,000 year old cave bear from Kudaro 1 cave in the Caucasus Mountains. Analysis of this genome alongside those of several Late Pleistocene cave bears reveals widespread mito-nuclear discordance in this group. Using the time interval between Middle and Late Pleistocene cave bear genomes, we directly estimate ursid nuclear and mitochondrial substitution rates to calibrate their respective phylogenies. This reveals post-divergence mitochondrial transfer as the dominant factor explaining their mito-nuclear discordance. Interestingly, these transfer events were not accompanied by large-scale nuclear introgression. However, we do detect additional instances of nuclear admixture among other cave bear lineages, and between cave bears and brown bears, which are not associated with mitochondrial exchange. Genomic data obtained from the Middle Pleistocene cave bear petrous bone has thus facilitated a revised evolutionary history of this extinct megafaunal group. Moreover, it suggests that petrous bones may provide a means of extending both the magnitude and time depth of palaeogenome retrieval over substantial portions of the evolutionary histories of many mammalian clades.
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Post by OldGreenGrolar on Feb 21, 2021 5:24:57 GMT -5
Reply 8. These bones look so heavy.
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Post by brobear on Feb 22, 2021 15:54:01 GMT -5
phys.org/news/2021-02-dna-year-old-bone-reveals-oldest.html?fbclid=IwAR0Yt_SGSkhFj0s6uj5ZVulOmaJv38DgP1eFuoklmIy0QyQqw1GeqbUg1Cc DNA from 360,000-year-old bone reveals oldest non-permafrost genome Scientists have successfully sequenced the genome of an extinct cave bear using a 360,000-year-old bone—the oldest genome of any organism from a non-permafrost environment. The work, involving Nottingham Trent University and the University of Potsdam in Germany, has revealed a new evolutionary history for the giant cave bear, which became extinct about 25,000 years ago. As part of the study, the team found that cave bears and their living relatives—the brown bear and polar bear—diverged from a common ancestor about 1.5 million years ago. They also found that many significant events in bear evolution may have been driven by major global climate change about one million years ago, when cold phases—or ice ages—became longer and more intense and warm phases much shorter. Cave bears, which grew larger than brown bears, weighing up to a ton, were widespread across Eurasia during the Pleistocene. They coexisted with brown bears and interbred with them, and modern brown bears still carry traces of extinct cave bear in their genomes. The sample analyzed by the researchers was from a cave bear which inhabited the Southern Caucasus, in what is now Georgia, around the Middle Pleistocene. The oldest DNA sequences have previously come from permafrost environments where DNA is much better preserved. For this study, however, the researchers wanted to push back the time limit of paleogenome sequencing much further into warmer, temperate zones, which were home to a far greater range of species. The work involved extracting the ancient DNA from a tiny piece of petrous bone (0.05g) part of the skull that contains the organs of the inner ear and which is known to be resistant to contamination from external DNA sources. The DNA was then prepared for sequencing, producing billions of individual short DNA sequences which represented a mixture of DNA from the cave bear and contaminants the bone had picked up over hundreds of thousands of years. Computational analysis was used to sort the target sequences from the contamination, which is done my matching the short sequences to a reference genome of a related organism, in this case the polar bear.
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Post by brobear on Apr 21, 2021 3:13:49 GMT -5
dinoanimals.com/animals/cave-bear-ursus-spelaeus/ Interestingly, cave bear were bigger during the Ice Age - and smaller when glaciation receded - this was most likely due to an adjustment in heat loss - the larger the animal, the slower it loses heat.
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Post by OldGreenGrolar on Apr 26, 2021 20:59:31 GMT -5
/\ So the cave bear does vary in size to a degree. Animals in colder climates seem to be dimensionally bigger than these from hotter countries mainly due to thick fur coat and extra layer of fat as well.
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Post by brobear on May 13, 2021 5:21:35 GMT -5
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Post by OldGreenGrolar on May 13, 2021 16:20:16 GMT -5
I see U.Artos is closely related to the cave bears. No wonder it has its shoulder hump. |
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Post by brobear on May 13, 2021 23:59:45 GMT -5
I see U.Artos is closely related to the cave bears. No wonder it has its shoulder hump. Brown bears evolved from the Etruscan Bear in Asia. Cave bears evolved from the Etruscan Bear in Europe. |
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Post by brobear on Jun 9, 2022 8:37:47 GMT -5
Morphometric analyses of cave bear mandibles (Carnivora, Ursidae)
December 2018R
Abstract and Figures:
Morphometric variability of cave and brown bears and their ancestors (Ursus minimus and U. etruscus) is examined using multivariate statistics based on measurements of 679 mandibles from 90 localities in Northern Eurasia. The variability is dependent on sexual dimorphism in size: it is well seen in big cave bears (U. spelaeus, U. kanivetz = ingressus, U. kudarensis), whose males are nearly 25% larger than females. In the morphological space, we identified two main types of mandibles: the “arctoid” type [U. minimus, U. etruscus, U. arctos, U. rodei (?)], and the “spelaeoid” type (U. spelaeus spelaeus, U. s. eremus, U. kanivetz, U. kudarensis). The intermediate “deningeroid” type includes U. deningeri, U. savini, U. rossicus (males), and U. spelaeus ladinicus. An additional unit is formed by female sample of U. rossicus. The mandible bones are less informative for understanding of cave bear evolution, because in comparison to crania, they have a rather simple shape.
*More to read on site.
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