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Post by brobear on Mar 26, 2017 3:47:01 GMT -5
The giant cave bear of Europe ( Ursus spelaeus ) is the grizzly's closest relative with the exception of the polar bear. This massive bear outweighed even today's Kodiak bear. Unlike the grizzly which prefers to dig his own winter den, the cave bears often hibernated in natural caves when such could be found. Sometimes cave lions would enter these caves in search of bear cubs ( an easy kill ). There were sometimes terrible fights deep within those dark caves between bear and lions. An even bigger threat to these huge bears were the Neanderthal people. It is believed by some authorities that the cave men both hunted and worshipped the great bears. This belief is evidenced by cave paintings and bountiful cave bear skulls collected by the cave men. The cave bear shared his environment with the grizzly. Each can be recognized by the shape of the skull. The cave bear has a broader skull with a distinctive stop or forehead described by some as being more "Teddy Bear-Like." The grizzly has a longer narrower skull with a sloping forehead. The famous giant European cave bear ( Ursus speleaus speleaus is now known to have been a pure vegetarian while the grizzly was and is an omnivore. During the Pleistocene, the grizzly was from 80% to 90% carnivorous.
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Post by brobear on Mar 26, 2017 4:18:13 GMT -5
www.dailymail.co.uk/sciencetech/article-3759796/Can-vegan-make-EXTINCT-Picky-prehistoric-cave-bear-s-diet-caused-die-out.html Weighing more than half a ton and equipped with huge teeth capable of crushing bones, the prehistoric cave bear would seem equipped to be a top Ice Age predator. But new research suggests these enormous bears may actually have been absurdly picky eaters that survived on a largely vegan diet. The findings provide new clues for what led these beasts to die out around 25,000 years ago during the last glacial period. While most modern bears are omnivorous, consuming everything from tiny berries to fish and deer, analysis of bones from extinct cave bears has revealed that they stuck to a strictly plant-based diet. Using cave bear bones found at the Goyet Cave in Belgium, a team of international researchers managed to reconstruct the bears' diet. Specifically, they looked at the isotope composition of collagen in the bones. Collagen - a protein that makes up the scaffolding of most tissues including bones, teeth, tendons and skin - is made up of amino acids that vary according to an animal's diet. The analysis eventually revealed cave bears lived on subsisted on a rigidly vegan diet. Even bear cubs that had been suckling milk showed a vegan-like collagen make-up due to their mother's dietary regime. 'Similar to today's giant panda, the cave bears were therefore extremely inflexible in regard to their food,' said lead researcher Professor Hervé Bocherens, from the Senckenberg Center for Human Evolution and Palaeoenvironment at the University of Tübingen in Germany. 'We assume that this unbalanced diet, in combination with the reduced supply of plants during the last ice age, ultimately led to the cave bear's extinction.' Cave bears first appeared in Europe around 400,000 years ago. Measuring up to 11 feet (3.5m) long and 5.5 feet tall at the shoulder (1.7m) they were formidable animals. They earned their name as many remains of these beasts have been found in caves. However, they are only thought to have hibernated in caverns and spent most of their time roaming searching for food. 'We believe that the reliance on a purely vegan diet was a crucial reason for the cave bear's extinction,' Professor Bocherens added, whose work is published in the Journal of Quaternary Science. The team is now hoping to study cave bear bones from other areas in order to confirm their hypothesis. 'We now intend to examine additional cave bear bones from various European locations with this new method, as well as conducting controlled feeding experiments with modern bears, in order to further solidify our proposition,' Professor Bocherens explained. Read more: www.dailymail.co.uk/sciencetech/article-3759796/Can-vegan-make-EXTINCT-Picky-prehistoric-cave-bear-s-diet-caused-die-out.html#ixzz4ITZ06SxM Follow us: @mailonline on Twitter | DailyMail on Facebook
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Post by brobear on Mar 26, 2017 4:19:28 GMT -5
THE GIANT VEGAN BEAR OF THE ICE AGE
Cave bears were long up to 11.4 feet (3.5 m) and boasted a height of 5.5 feet (1.7 m) at the shoulder Cave bears are first thought to have appeared in Europe around 400,000 years ago before going extinct 24,000 years ago. They were far larger than most bears found living today, measuring up to 11 feet (3.5m) long. Males could weigh up to a ton but on average 500 kg. ( 1,100 pounds ). With teeth far larger than modern bears, they were thought to have had a diet that had a larger amount of bone than their contemporary relatives. Despite their name, cave bears did not live in caves--still , over time scientists have found thousands of bear bones in caverns where the animals holed up to hibernate. Most of the animals that have been found appear to have died during hibernation, which is what has led to their common name. They sought out sheltered caverns and caves to escape the cold winter. They are thought to have lived in low forests in mountainous terrain, perhaps because these would have provided a wide range of food for them.
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Post by brobear on Mar 26, 2017 4:31:01 GMT -5
news.westernu.ca/2016/09/diet-discovery-shifts-thinking-prehistoric-bear/ Diet discovery shifts thinking on prehistoric cave bear SEPTEMBER 21, 2016 BY PAUL MAYNE Newly discovered information into the inflexible diet of one group of prehistoric bears has scientists rethinking how the creatures lived and what caused the large mammals’ extinction some 25,000 years ago. Working with scientists in Japan, Belgium and Germany, Western biologist Keith Hobson used an isotopic composition found in the collagen of the cave bears’ bones to show the large mammals subsisted on a purely vegan diet. In the study, recently published in the Journal of Quaternary Science, the international team proposed this inflexible diet killed off the bears. “It’s almost a paradigm shift to what we were always thinking,” Hobson said. “Now, we have to rethink how they existed on the landscape and, more importantly, why they went extinct. Did they have the wrong strategy all along? Being herbivores were they therefore particularly prone to any kind of climate change? If the weather turned cold, they would not do well, whereas omnivores and carnivores would look for other sources of food. “Because their niche was so specialized, they were vulnerable to such changes. Any animals that feed on only one thing are very vulnerable. That makes sense ecologically.” The Cave Bears of Belgium lived in Europe during the most recent glacial period, approximately 400,000 years ago. With a length of 3.5 metres and a height of 1.7 metres at the shoulder, these bears were noticeably larger than their modern-day relatives. Despite their name, they did not live in caves but only used them for hibernation. Researchers analyzed amino acid in the bone collagen of 10 cave bears skeletons (eight adults, two cubs), five brown bears from Goyet Cave in Belgium and three modern grizzly bears from Alberta. All the cave bears, as well as some brown bears, had the feeding habits of herbivores (plant eaters). Today’s brown bears are omnivores (feeding on both plants and animals) and, depending on the time of year, will devour plants, mushrooms, berries, smaller to larger mammals, fish and insects. Cave bears were a different story. “Similar to today’s giant panda, the cave bears were extremely inflexible in regard to their food,” he said. “We assume that this unbalanced diet, in combination with the reduced supply of plants during the last ice age, ultimately led to the cave bear’s extinction.” Because they were vegan, researchers believe the creatures were slower and less aggressive than one would expect of a large bear. That may have made them more vulnerable to hunters. “This adds a whole new dimension to the discussion,” said Hobson, who worked with Hervé Bocherens, a former Western postdoctoral scholar, now a professor in the Department of Geosciences at the University of Tübingen in Germany. “The reliance on a purely vegan diet was a crucial reason for the cave bear’s extinction,” Bocherens said. “We now intend to examine additional cave bear bones from various European locations with this new method, as well as conduct controlled feeding experiments with modern bears, in order to further solidify our proposition.” This new interpretation around the extinction of the cave bear has added to a body of evidence as to why some species continue to thrive, while others remain on the brink of extinction. “There are many existing bear species – some more vulnerable than others, such as the polar bear – who have a very specialized diet,” Hobson said. “Understanding what happened to their ancestors in the past, where they may have gone down the wrong way, can help you with modern-day conservation issues, especially now with such a flux in environmental changes. “Are there factors today that could put species at risk for the very same reasons? A specialized diet? Not being able to get out of that niche they are in? What do we do about those ones? So this research does have a modern day equivalent.”
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Post by brobear on Mar 26, 2017 4:41:40 GMT -5
www.foxnews.com/story/2008/01/09/prehistoric-cave-bears-werent-so-cuddly-after-all.html Prehistoric Cave Bears Weren't So Cuddly After All By Charles Q. Choi Published January 09, 2008 Our ancestors had lots of predators and competitors to worry about — saber-toothed cats, dire wolves and even giant man-eating birds of prey. Now you can add cave bears to that list. These prehistoric giants were roughly a third larger than modern grizzly bears. • Click here to visit FOXNews.com's Evolution & Paleontology Center. Previously, scientists thought cave bears were just vegetarians, evoking an image of gentle giants that fed solely on berries and roots. Now bones from the Carpathians — the mountains where Dracula supposedly dwelt — suggest cave bears could have also been carnivores, and possibly even cannibals. Bad to the bone Cave bears (Ursus spelaeus) are named after the places where their bones are commonly found — caves across Europe. They died out roughly 20,000 years ago, when ice dominated the Northern Hemisphere. For the past 30 years, studies of their skulls, jaws and teeth suggested cave bears might have been largely herbivorous. In addition, the bones of central and western European cave bears matched those of vegetarians in having low levels of nitrogen-15, whose atomic nucleus has one more neutron than common nitrogen-14 does. Animals accumulate nitrogen-15 in their bodies, and animals that eat animals — that is, carnivores — build up more nitrogen-15 than herbivores do. Still, black bears and brown bears are omnivores. This suggested that although some cave bears were largely vegetarian, others might have been more carnivorous. New data from the Pestera cu Oase ("Cave with Bones") in the southwestern tip of the Carpathian mountains in Romania now hints most of its cave bears were significantly carnivorous, due to their high nitrogen-15 levels. Hidden caves Retrieving the bones was not easy. "It is a pretty inaccessible cave that you need to go underwater to get to," said researcher Michael Richards, an archaeologist at the Max Planck Institute for Evolutionary Anthropology at Leipzig, Germany. The cave entrances the bears once used collapsed long ago, so one had to reach the bones through a lower level, going through an active spring and an underground river. To reach the Pestera cu Oase, which was discovered by inquisitive Romanian cavers, scuba equipment and climbing gear are necessary. "On a daily basis, you can imagine that it meant a lot of very hard work for my small excavation team, and also that it was not exempt of some risk," said researcher Joao Zilhao, a Paleolithic archaeologist at the University of Bristol in England. Bears vs. humans The findings suggest these cave bears could have struggled over meat with humans and the other carnivores of the time — hyenas, wolves and cave lions — as well as omnivores such as brown bears. "It would be interesting to measure more cave bears from other sites in this region to see if we find other carnivorous cave bears," Richards said. "It would also be interesting trying to determine why these bears were carnivores when other cave bears weren't." The researchers suggest the cave bears might have eaten fish, but another possibility is "some degree of bear-bear cannibalism," said University of Arizona zooarchaeologist Mary Stiner, who did not participate in this study. In brown bears, "cannibalism and eliminating rivals and young go hand in hand, as in lions. This behavior is also clear from very large cave bear tooth marks on young cave bear skulls in Yarimburgaz Cave in western Turkey." These results might also shed light on cave bear bones that humans and Neanderthals apparently placed in these caves in ancient times. These actions "are often interpreted as some sort of ritual or symbolic behavior, and I wonder if cave bears were particularly compelling for humans if they were also a competitor," Richards told LiveScience. The international team of researchers detailed its findings online Jan. 7 in the journal Proceedings of the National Academy of Sciences.
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Post by brobear on Mar 26, 2017 4:44:34 GMT -5
( in my own words )... I just learned this from a highly respected poster called "GrizzlyClaws"... The giant cave bear Ursus spelaeus was a pure vegan while the giant cave bear of South East Europe, Ursus ingressus was a mostly carnivorous omnivore. This eradicates a great deal of confusion.
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Post by brobear on Mar 26, 2017 5:06:55 GMT -5
www.newworldencyclopedia.org/entry/Cave_bear Cave bear is the common name for a large bear, Ursus spelaeus, that lived in Europe during the Pleistocene about 250,000 years ago and became extinct at the end of the last ice age about 12,000 years ago. Both the common name, cave bear, and the scientific name, spelaeus, derive from the fact that fossils of this species were found mostly in caves, suggesting that this species spent more time in caves than the related brown bear, which only uses caves for hibernation. As a result of its habitat, Ursus spelaeus is the species of macro fauna that has resulted in the largest amount of Pleistocene fossils in caves (Orlando et al. 2002).Human beings have long been fascinated by their own history, and cave bears have shared part of that history, living at the same time as modern human beings (Homo sapiens sapiens) and the Neanderthals. Many mysteries remain about the cave bear and about its interaction with humans, which remain active foci of human inquiry, including the employment of new technologies such as DNA analysis (Noonan et al. 2005). Time period, range, and habitatThe cave bear, Ursus spelaeus, was prominent during the Pleistocene. The Pleistocene epoch of the geologic timescale is the period from 1,808,000 to 11,550 years Before Present (BP). The Pleistocene follows the Pliocene epoch and is followed by the Holocene epoch. The end of the Pleistocene corresponds with the end of the Paleolithic age used in archaeology. Cave bears inhabited Europe and the Near East since the Riss glacial period, 250,000 years ago (Orlando et al. 2002). They became extinct approximately 12,000 years ago, at the end of the last glacial period (Orlando et al. 2002).The cave bear's range stretched across Europe, from Spain to Eurasia, from Italy and Greece to Belgium, the Netherlands and possibly Great Britain, across a portion of Germany, through Poland, then south into Hungary, Romania, and parts of Russia. There have been no traces of cave bears living in northern Britain, Scandinavia, or the Baltic countries, which were covered in extensive glaciers at the time. The largest numbers of cave bear remains have been found in Austria, Switzerland, southern Germany, northern Italy, northern Spain, Croatia, Hungary, and Romania. The huge number of bones found in south, central, and east Europe has led some scientists to think that Europe may have once had literal herds of cave bears. Some, however, point out that though some caves have thousands of bones, they were accumulated over a period of 100,000 years or more, thus requiring only two deaths in a cave per year to account for the large numbers (Bieder 2005).The cave bear inhabited low mountainous areas, especially in regions rich in limestone caves. They seemed to avoid open plains, preferring forested or forest-edged terrains (Bieder 2005).Many caves in Europe have skeletons of cave bears on display, for example the Heinrichshöhle in Hemer or the Dechenhöhle in Iserlohn, Germany. In Romania, there is a cave called Peştera Urşilor (bears' cave) where numerous cave bear skeletons were discovered. Anatomy The cave bear was a massive bear, characterized by a very broad, domed skull with a steep forehead, unlike the more gradual sloping forehead in skulls of modern bears. Cave bears of the last ice age lacked the usual two to three premolars present in other bears; to compensate, the last molar is very elongated, with supplementary cusps (Altabadia).The cave bear's stout body had long thighs, massive shins, and in-turning feet, making it similar in skeletal structure to the grizzly bear. The average weight for males is estimated to have been 400 kilograms (880 pounds) (Brown 1993). Certain experts suggest greater weights of 500-600 kilograms (1,102-1,323 pounds) (Pastoureau 2007). The modern brown bear, Ursus arctos, weighs between 130 and 700 kilograms (286-1540 pounds), with the larger populations matching the polar bear, Ursus maritimus (300 to 600 kilograms) (660 to 1320 pounds) as the largest extant bear.Males were larger than females. About ninety percent of cave bear skeletons in museums are male, due to a misconception that the female skeletons were merely "dwarfs." Cave bears grew larger during glaciations and smaller during interglacials, probably to adjust heat loss rate (MacDonald 1992). Dietary habitsThe dietary habits of cave bears—whether largely vegetarian, or also carnivores or scavengers—is unsettled.The morphological features of chewing apparatus of cave bears suggest herbivorous behavior, rather than predatory behavior, and important adaptations to a tough vegetarian diet (Pinto Llona 2006). On the other hand, comparison with extant European brown bears, Ursus arctos, in terms of gross-wear features on the teeth, suggests that tubers were absent from the cave bear diet and not responsible for the extreme wear seen in cave bear teeth (Pinto Llona 2006). Dental Microwear Analysis (DMA), comparing diet-related microscopic dental wear features of brown bears, whose diet is known, with cave bears suggests that the cave bear dietary behavior included a greater consumption of bone versus that of brown bears.Results obtained on the stable isotopic yield of cave bear bones also are interpreted as indicators of a largely vegetarian diet, and one even more vegetarian than contemporary herbivorous taxa (Bocherens et al. 1994; Pinto Llona 2006). The bones of central and western European cave bears matched those of vegetarians in having low levels of nitrogen-15, which is accumulated by meat eaters. However, several cave bear sites in the Peştera cu Oase in the southwestern tip of the Carpathian mountains have shown that the cave bears of that region may have been largely carnivorous, due to higher levels of nitrogen-15 in their bones (Choi 2008). Nitrogen-15 is accumulated by animals and, thus, carnivores, which eat animals, accumulate more nitrogen-15 in their bodies than do herbivores.Carnivorous behavior is also evident from very large cave bear tooth marks on young cave bear skulls in Yarimburgaz Cave in western Turkey (Choi 2008).Taphonomic analysis of modifications on cave bear bones produced by carnivores suggests that in addition to their herbivorous and carnivorous behaviors, cave bears actively scavenged on the carcasses of their con-specifics (Pinto Llona 2006).It is possible that different populations of cave bears had different dietary habits, including possible bear-bear cannibalism (Choi 2008) and cannibalistic scavenging behavior. In the case of the central and western European populations, whose bones lacked an identifiable isotopic signature of nitrogen-15, it is possible that cannibalistic scavenging behavior may have been quite limited, relative to the more dominant vegetarian diet, leaving no trace (Pinto Llona 2006). MortalityCave bear longevity is unknown, though it has been estimated that they seldom exceeded 20 years of age (Bieder 2005).Some cave bear bones show signs of numerous different ailments, including fusion of the spine, bone tumors, cavities, tooth resorption, necrosis (particularly in younger specimens), nematodes, osteomyelitis, periostitis, rickets, and kidney stones (Brown 1993). Male cave bear skeletons have been found with broken baculums, probably due to fighting during breeding season (Bjorn 1968). Death during hibernation is considered to have been a common end for cave bears, mainly befalling specimens that failed ecologically during the summer season through inexperience, sickness, or old age (Bjorn 1968).Paleontologists doubt adult cave bears had any natural predators, save for pack hunting wolves and cave hyenas, which would probably have attacked sick or infirm specimens (Bieder 2005). Cave hyenas are thought to be responsible for the dis-articulation and destruction of some cave bear skeletons. Such large carcasses would have been an optimal food resource for the hyenas, especially at the end of the winter, when food was scarce (Diedrich and Zak 2006). Evolution and extinction The cave bear is thought to be descended from the plio-pleistocene Etruscan bear (Ursus etruscus) through the Deninger's bear (Ursus deningeri) of the Pleistocene half a million years ago.Cave bears found in different regions vary in age and evolutionary advancement, thus facilitating investigations into their development. The three anterior premolars were gradually reduced, then disappeared. In a fourth of the skulls found in the Conturines, the third premolar is still present, while the other more evolved specimens elsewhere lack it. The fourth premolar developed into a molar. The last remaining premolar became conjugated with the true molars, enlarging the crown and granting it more cusps and cutting borders. This phenomenon known as molarization improved the mastication capacities of the molars, facilitating the processing of tough vegetation. This allowed the cave bear to gain more energy for hibernation while eating less than its ancestors (Altabadia). Molecular phylogenetic analysis of mtDNA suggests that cave bears and brown bears separated from a common ancestor about 1.2 to 1.6 million years ago (Orlando et al. 2002).Experts generally agree on the time of the extinction of the cave bear—about 12,000 years ago at the end of the late glacial period (Orlando et al. 2002)—but they remain in dispute about the causes of the extinction. Some have proposed that the bears' large size and lack of natural predators caused them to degenerate as a species, while others claim that habitat loss due to climate change was responsible for the extinction. Yet another group of experts disputes this claim, as the cave bears had earlier survived multiple episodes of climate change. In their key article on ancient DNA and the population genetics of the cave bear, Orlando et al. (2002) note that climatic changes may have altered the bears' genetic diversity profiles in ways that pushed the bears to their extinction. They note that the cave bear started to become extinct during cold climatic conditions accompanied by an observed simultaneous and significant loss of genetic diversity.Overhunting by humans has been largely dismissed due to the fact that human populations at the time were too small to pose a serious threat to the cave bears' survival, though there is proof that the two species may have competed for living space in caves. One theory proposed by late paleontologist Bjorn Kurten states that the cave bear populations were fragmented and under stress even before the advent of the glaciers (Bieder 2005). Cave bear worshipCollections of bear bones at several widely dispersed sites suggest that Neanderthals may have worshiped cave bears, especially at Drachenlock, in Switzerland, where a stone chest was discovered with a number of bear skulls stacked upon it. Neanderthals, who also inhabited the entrance of the cave, are believed to have built it. A massive stone slab covered the top of the structure. At the cave entrance, seven bear skulls were arranged with their muzzles facing the cave entrance, while still deeper in the cave, a further six bear skulls were lodged in niches along the wall. Next to these remains were bundles of limb bones belonging to different bears. Consequently, it was at this site that the supposed symbol of the "Cult of the Cave Bear" was found. This consisted of the skull of a three-year-old bear pierced in the cheek area by the leg-bone of younger bear. The arrangement of these bones of different bears are not believed to have happened by chance.A similar phenomenon was encountered in Regourdou, southern France. A rectangular pit contained the remains of at least twenty bears, covered by a massive stone slab. The remains of a Neanderthal lay nearby in another stone pit, with various objects, including a bear humerus, a scraper, a core, and some flakes, which were interpreted as grave offerings.The unusual finding in a deep chamber of Basua Cave in Savona, Italy, is thought to be related to cave bear worship, as there is a vaguely zoomorphic stalagmite surrounded by clay pellets. It was apparently used by Neanderthals for a ceremony, the fact that bear bones lay scattered on the floor further suggested that this was likely to have had some sort of ritual purpose (de al Cova).
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Post by brobear on Mar 26, 2017 5:09:00 GMT -5
Cave Bear..... References Altabadia. n.d. Gli orsi spelèi delle Conturines. Altabadia. Retrieved April 18, 2008. Bieder, R. 2005. Bear. London: Reaktion. ISBN 1861892047. Kurten, B. 2007. Pleistocene Mammals of Europe. New Brunswick, N.J.: AldineTransaction. ISBN 0202309533. Bocherens, H., M. Fizet, and A. Mariotti. 1994. Diet, physiology and ecology of fossil mammals as inferred from stable carbon and nitrogen isotope biogeochemistry: implications for Pleistocene bears. Palaeogeography, Palaeoclimatology, Palaeoecolology 107: 213-225. Brown, G. 1993. Great Bear Almanac. New York: Lyons & Burford. ISBN 1558212108. Choi, C. O. 2008. Prehistoric cave bears weren't so cuddly after all. FOXNews, January 9, 2008. Retrieved April 18, 2008. de la Cova, C. M. n.d. Burial, ritual, religion, and cannibalism. Neandertals.com. Retrieved April 18, 2008. Diedrich, C. G., and K. Zak. 2006. Prey deposits and den sites of the Upper Pleistocene hyena Crocuta crocuta spelaea (Goldfuss, 1823) in horizontal and vertical caves of the Bohemian Karst. Bulletin of Geosciences 81(4): 237-276. Macdonald, D. 1992. The Velvet Claw. BBC Books. ISBN 0563208449. Noonan, J. P., M. Hofreiter, D. Smith, J. R. Priest, N. Rohland, G. Rabeder, J. Krause, J. C. Detter, S. Pääbo, and E. M. Rubin. 2005. Genomic sequencing of Pleistocene cave bears. Science 309(5734): 597-599. Orlando, L., D. Bonjean, H. Bocherens, A. Thenot, A. Argant, M. Otte, and C. Hänni. 2002. Ancient DNA and the population genetics of cave bears (Ursus spelaeus) through space and time. Molecular Biology and Evolution 19:1920-1933. Retrieved April 18, 2008. Pastoureau, M. 2007. L’ours; Histoire d’un roi dechu. Paris: Seuil. ISBN 202021542X. Pinto Llona, A. C. 2006. Comparative dental microwear analysis of cave bears Ursus spelaeus Rosenmüller, 1794 and brown bears Ursus arctos Linnaeus, 1758. Scientific Annals, School of Geology Aristotle University of Thessaloniki (AUTH), Special volume 98: 103-108. Retrieved April 18, 2008. Credits New World Encyclopedia writers and editors rewrote and completed the Wikipedia article in accordance with New World Encyclopedia standards. This article abides by terms of the Creative Commons CC-by-sa 3.0 License (CC-by-sa), which may be used and disseminated with proper attribution. Credit is due under the terms of this license that can reference both the New World Encyclopedia contributors and the selfless volunteer contributors of the Wikimedia Foundation.
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Post by brobear on Mar 26, 2017 5:11:40 GMT -5
www.researchgate.net/publication/285832124_Late_PLeistocene_cave_bears_Ursus_ex_gr_spelaeus_from_the_Medvedia_cave_in_the_Janska_Valley_the_low_Tatras_Mts_Slovakia www.researchgate.net/publication/263414302_Isotopic_evidence_for_dietary_flexibility_among_European_Late_Pleistocene_cave_bears_Ursus_spelaeus The proposed dietary pattern of extinct Late Pleistocene cave bears (Ursus spelaeus Rosenmüller, 1794) has become controversial, as some authors have suggested that they were strictly vegetarian, whereas others maintain they were omnivores that at times ate large amounts of animal protein. We evaluated these alternatives by compiling stable isotope data of carbon (δ13C) and nitrogen (δ15N) from the bone collagen of adult European cave bears from the Late Pleistocene (Marine Isotopic Stage 3). The data include previously published analyses and additional data from the southeastern European (Carpathian) sites of Cioclovina, Muierii, Oase, and Urşilor. The cave bear isotopic values from bone collagen were compared with those from hair keratin occurring in grizzly bears (Ursus arctos horribilis Ord, 1815) collected from 1989 to 2009 in the western United States (Yellowstone National Park). The Yellowstone bears have access to a wide diversity of plants and animals, such that their diets can range from vegetarian to carnivorous. Thus, there was considerable δ13C and δ15N variation among the grizzly bear isotopic values, and the cave bear isotopic variation was encompassed within the overall grizzly bear isotopic distribution. More importantly, the δ15N distributions, reflecting principally trophic level, were not different between the cave bears and the grizzly bears; the cave bear values are, on average, slightly higher or lower than those of the grizzly bears, depending on the criteria for inclusion in the comparisons. It is therefore no longer appropriate to view Late Pleistocene cave bears as strictly or even predominantly vegetarian but as flexible omnivores within their diverse communities.
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Post by brobear on May 19, 2017 3:21:44 GMT -5
Two cave bears that died in Austria more than 40 000 years ago have had their nuclear DNA sequenced. The technique used to recover sequences from a tooth and a bone has more than doubled the age at which this kind of DNA can be recovered - and could mean Neanderthals are next. Recovering genetic material from ancient remains is fraught with difficulty because DNA degrades rapidly and is easily contaminated. Most successful studies have focused on the more abundant mitochondrial DNA, but this is much less useful. In exceptional cases nuclear DNA has been extracted from remains less than 20 000 years old if preserved in permafrost or desert environments. Now Eddy Rubin of the US Department of Energy's Joint Genome Institute in Walnut Creek, California, and his team have turned to computers for help. They sequenced everything in the sample, contamination and all, then picked out sequences averaging 70 base pairs that matched parts of the dog genome - chosen because it is the closest relative of bears to have a fully sequenced genome. They recovered nearly 27 000 base pairs of nuclear DNA from the cave bears, which became extinct around 15 000 years ago (Science, DOI: 10.11261science.1113485). "it is a significant advance to show that so much nuclear DNA is actually being preserved," says Beth Shapiro, who studies ancient DNA extraction at the University of Oxford. "This is very much a proof of principle," says Rubin. "We're not interested in cave bears - we're interested in Neanderthals." Text and Photo from the weekly science magazine New Scientist 11 June 2005 From: news.nationalgeographic.com/news/2005/06/0606_050606_alpsbears.html sites.google.com/site/savebearsnow/cavebears,atlasbearsandmore
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Post by brobear on May 19, 2017 3:22:48 GMT -5
sites.google.com/site/savebearsnow/cavebears,atlasbearsandmore Ancient Bear DNA Mapped -- A First for Extinct Species cavebear skull Photograph copyright Gernot Rabeder, Institute of Paleontology, University of Vienna, Vienna, Austria Stefan Lovgren for National Geographic News June 6, 2005 Scientists have sequenced the DNA of two cave bears that roamed the Austrian Alps some 40 000 years ago. It marks the first time researchers have been able to completely sequence the DNA of a species that has long been extinct. The research opens the door to sequencing the DNA genome of other extinct species, including the Neandertals (often spelled "Neanderthals"). "We have shown that it is possible to sequence the genome of a long-extinct organism, something previously considered to be in the realm of science fiction," said James Noonan, a geneticist and postdoctoral fellow in the genomics division at the Lawrence Berkeley National Laboratory in California. Noonan is the lead author of the study, which appeared in the June 2 online edition of the journal Science. DNA Nucleus Until now scientists have been unable to extract pure DNA from the cell nuclei of ancient animals. Not only does DNA start to degrade at death, but the microbes that eat away at dead animals contaminate genomic DNA, which is found in cell nucei. Other contaminants may include human DNA left through contact, such as when a scientist handles the bones. Rather than use genomic DNA, most studies of ancient DNA have used mitochondrial DNA. A sort of cellular power plant, mitochondria have their own type of DNA and are believed to have evolved separately from genomic DNA. Only genomic DNA, however, can help scientists understand the functional differences between extinct and living species. Because unbroken strands of ancient DNA are so hard to come by, previous ancient-DNA studies have used a biochemical amplification method to create a string of DNA. In effect, they take an unbroken fragment of DNA and copy it over and over to create a complete strand. But this only works for mitochondrial DNA, not genomic DNA. Needle in a Haystack This time the scientists took a different approach. First they extracted genomic DNA from two 40,000-year-old cave bear bones from Austria. Extinct for more than 10,000 years, cave bears (Ursus spelaeus) were related to the ancestors of modern brown bears and polar bears. Cave paintings show that ancient humans encountered cave bears. The researchers sequenced all of the genomic DNA they could get out of the cave bear bones. Without amplifying any of it, they then identified each sequence by comparing it to the complete dog-genome sequence that is publicly available. Dogs and bears, which diverged some 50 million years ago, are 92 percent similar on the sequence level. "[It was] sort of like looking for a needle in a haystack," said Eddy Rubin, the director of the U.S. Department of Energy's Joint Genome Institute in Walnut Creek, California, where the work was done. "Fortunately the computer was a great magnet for finding the needles we were interested in." About 6 percent of the sample that was sequenced yielded undamaged cave bear DNA, while the rest was a hodgepodge of microbial contaminants. Within those fractions of cave bear DNA were bits of genes. Comparing the ancient bear sequences with those of modern bears, the scientists showed that cave bears were more closely related to brown bears than to black bears. "It shows that we got enough ancient genomic DNA to learn something biologically relevant about the cave bear," Noonan said.
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Post by brobear on May 19, 2017 3:24:10 GMT -5
Human Evolution
The cave bear DNA sequencing opens the door to the testing of other extinct species, including our nearest prehistoric relatives, the Neandertals. The scientists say they plan to sequence the Neandertal genome over the next several years.
Another possibility is to apply these techniques to the remains of Homo floresiensis, found recently in Indonesia. Researchers nicknamed this human ancestor "the hobbit" because of its tiny stature.
H. floresiensis is believed to have diverged from modern humans two million years ago. Neandertals may have diverged from humans 500 000 years ago.
The successful DNA sequencing of the two human-ancestor species could help scientists describe the evolutionary events that led to modern humans.
What about sequencing the DNA from dinosaur fossils?
"Unfortunately, we don't think [that] will ever be possible," Noonan said. "DNA does not survive beyond a hundred thousand years under the environmental conditions in which we found our cave bear remains. And of course, dinosaur fossils are at least 65 million years old."
drawing Distribution of the cave bear, Ursus spelaeus, in the Pleistocene. Each dot represents one or more sites with fossils of the species; two North African records are uncertain. Only Holsteinian and later records are included. The actual number of sites is many times greater than the dots, and some sites may contain the remains of hundreds or thousands of bears.
Photo: Bjorn Kurten, 1976, 'The Cave Bear Story'
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Post by brobear on May 19, 2017 5:42:41 GMT -5
sciencenetlinks.com/science-news/science-updates/cave-bear/ They used state-of-the-art computer technology to separate the bear genes from the clutter. Jurassic Park fans should note that they can’t clone a new cave bear, nor can they recover DNA from creatures as old as the dinosaurs. But they do hope to reconstruct the genetic code of Neanderthals, our closest non-human relatives, to better understand how our own species evolved. I’m Bob Hirshon for AAAS, the Science Society.
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Post by brobear on Jan 27, 2018 20:51:19 GMT -5
twilightbeasts.wordpress.com/2014/07/02/the-bear-necessities/ Humans and bears have a strange relationship. On the one hand we see them as lovable, smart, curious creatures (think Baloo from the Jungle Book). On the other, we have taken great pains to exterminate them wherever and whenever we could. Thankfully, no bear species has gone extinct for over 10,000 years (although many subspecies have been lost). During the Pleistocene, the old world was home to a complex of species that may have been amongst the biggest of bears. The cave bear (Ursus spelaeus) was perhaps the first Twilight Beast to be studied in a scientific sense, thanks to the millions of bones the animal left behind in caves throughout Europe and Asia, the legacy of many individuals who failed to survive hibernation. Thought to have inspired legends of dragons that lived in caves, the bones were so numerous that they were occasionally mined as a source of phosphate. Named way back in the 18th century by Johann Christian Rosenmüller, the cave bear has been at the forefront of Pleistocene research ever since. This vanguard position continues into the present day: Ursus spelaeus was the first extinct mammal to have its nuclear genome sequenced. The oldest mitochondrial genome we have is that of a Middle Pleistocene cave bear ( and it was used to test methods that were later utilised to sequence DNA from Homo heidelbergensis ). The cave bear (along with other “species” within the complex such as Ursus ingressus, Ursus deningeri) was a huge animal. Larger than the largest Kodiak brown bears (Ursus arctos), this imposing creature was probably a strict vegetarian rather than an omnivore. Analysis of teeth micro-abrasions and the stable isotopes that were incorporated into the bones show that these were gentle giants (although, giant herbivores are not to be underestimated, as anyone who lives around hippos or elephants will tell you). They may have been one of the main prey of another Pleistocene predator, the cave lion (Panthera spelaea). One can imagine a stealthy lion, winding through the winter caves, picking off the hibernating bears. We still find traces of the lifestyle of the vanished cave bear within European caves. Many caves, including the famous Chauvet, still have visible marks from where the animal sharpened their claws on the walls. In some cases Palaeolithic people incorporated the marks into their art. Some caves (e.g. Große Klingerberg Höhle in Bavaria) have circular depressions visible in the cave floor, which have been interpreted as bear nests, caused by the animal turning in its sleep while hibernating. Speleologists have even recovered kidney stones from amongst the skeletons of cave bears. Perhaps the most evocative sign left by the cave bear, which speaks of how integral the species once was to the European ecosystem, and how long it was a part of it, is something known as Bärenschliffe. Simply put, this is stone found in narrow cave routes that has been polished to a reflective shine by the scratching and rubbing of thousands of cave bears over tens of thousands of years. Within these caves, the bears would have occasionally encountered another apex predator (Homo sapiens, Homo neanderthalensis). There are a few images within cave art that may be of the cave bear. Separating the paintings of brown bears and cave bears can be difficult but there are some morphological differences that can point us in the right direction. Compared to brown bears, cave bears have a huge protruding forehead, which is sometimes noticeable in cave art. The last cave bears probably died about 27000 calendar years ago, much earlier than the extinction of mammoth, woolly rhino, or cave lion. Genetic evidence suggests that this extinction occurred after a prolonged period of genetic bottlenecking. The cause is likely to have been a combination of change in climate affecting the nutritious vegetation the cave bear needed as well as an increase in pressure from Palaeolithic humans for cave sites.
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Post by brobear on Jan 31, 2018 5:15:41 GMT -5
www.outdoorhub.com/stories/2015/11/02/five-prehistoric-bear-species-mop-floor-modern-bears/ Existing in Europe during the Pleistocene and only becoming extinct 24,000 years ago, the cave bear was one of the largest bears to have ever called Europe home. Early researchers initially mistook fossils of these ancient bruins for polar bears, but subsequent investigation revealed a species related to the modern brown bear, albeit with broader skulls, longer thighs, and robust shins. Cave bears are about as large as the biggest modern bears. The characteristic that set cave bears apart from other bruins is of course, their tendency to live in caves year round. Unlike other bears, who only stay in caves briefly during hibernation, the spelaeus spend most of their time inside the limestone caves of Western Europe. In parts of Russia, where the bears frequently interacted with cave lions, the two apex predators battled constantly for territory. Both bears and lions would occasionally prey on each others’ young, and sometimes researchers would discover their skeletons intermixed in the same cave. Naturally, the winner of these fierce battles would also claim the cave for themselves.
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Post by brobear on Apr 10, 2018 11:31:04 GMT -5
www.newworldencyclopedia.org/entry/Cave_bear Cave bear is the common name for a large bear, Ursus spelaeus, that lived in Europe during the Pleistocene about 250,000 years ago and became extinct at the end of the last ice age about 12,000 years ago. Both the common name, cave bear, and the scientific name, spelaeus, derive from the fact that fossils of this species were found mostly in caves, suggesting that this species spent more time in caves than the related brown bear, which only uses caves for hibernation. As a result of its habitat, Ursus spelaeus is the species of macro fauna that has resulted in the largest amount of Pleistocene fossils in caves (Orlando et al. 2002). Human beings have long been fascinated by their own history, and cave bears have shared part of that history, living at the same time as modern human beings (Homo sapiens sapiens) and the Neanderthals. Many mysteries remain about the cave bear and about its interaction with humans, which remain active foci of human inquiry, including the employment of new technologies such as DNA analysis (Noonan et al. 2005). The cave bear, Ursus spelaeus, was prominent during the Pleistocene. The Pleistocene epoch of the geologic timescale is the period from 1,808,000 to 11,550 years Before Present (BP). The Pleistocene follows the Pliocene epoch and is followed by the Holocene epoch. The end of the Pleistocene corresponds with the end of the Paleolithic age used in archaeology. Cave bears inhabited Europe and the Near East since the Riss glacial period, 250,000 years ago (Orlando et al. 2002). They became extinct approximately 12,000 years ago, at the end of the last glacial period (Orlando et al. 2002). The cave bear's range stretched across Europe, from Spain to Eurasia, from Italy and Greece to Belgium, the Netherlands and possibly Great Britain, across a portion of Germany, through Poland, then south into Hungary, Romania, and parts of Russia. There have been no traces of cave bears living in northern Britain, Scandinavia, or the Baltic countries, which were covered in extensive glaciers at the time. The largest numbers of cave bear remains have been found in Austria, Switzerland, southern Germany, northern Italy, northern Spain, Croatia, Hungary, and Romania. The huge number of bones found in south, central, and east Europe has led some scientists to think that Europe may have once had literal herds of cave bears. Some, however, point out that though some caves have thousands of bones, they were accumulated over a period of 100,000 years or more, thus requiring only two deaths in a cave per year to account for the large numbers (Bieder 2005). The cave bear inhabited low mountainous areas, especially in regions rich in limestone caves. They seemed to avoid open plains, preferring forested or forest-edged terrains (Bieder 2005). Many caves in Europe have skeletons of cave bears on display, for example the Heinrichshöhle in Hemer or the Dechenhöhle in Iserlohn, Germany. In Romania, there is a cave called Peştera Urşilor (bears' cave) where numerous cave bear skeletons were discovered. The cave bear was a massive bear, characterized by a very broad, domed skull with a steep forehead, unlike the more gradual sloping forehead in skulls of modern bears. Cave bears of the last ice age lacked the usual two to three premolars present in other bears; to compensate, the last molar is very elongated, with supplementary cusps (Altabadia). The cave bear's stout body had long thighs, massive shins, and in-turning feet, making it similar in skeletal structure to the grizzly bear. The average weight for males is estimated to have been 400 kilograms (880 pounds) (Brown 1993). Certain experts suggest greater weights of 500-600 kilograms (1,102-1,323 pounds) (Pastoureau 2007). The modern brown bear, Ursus arctos, weighs between 130 and 700 kilograms (286-1540 pounds), with the larger populations matching the polar bear, Ursus maritimus (300 to 600 kilograms) (660 to 1320 pounds) as the largest extant bear. Males were larger than females. About ninety percent of cave bear skeletons in museums are male, due to a misconception that the female skeletons were merely "dwarfs." Cave bears grew larger during glaciations and smaller during interglacials, probably to adjust heat loss rate (MacDonald 1992). The dietary habits of cave bears—whether largely vegetarian, or also carnivores or scavengers—is unsettled. The morphological features of chewing apparatus of cave bears suggest herbivorous behavior, rather than predatory behavior, and important adaptations to a tough vegetarian diet (Pinto Llona 2006). On the other hand, comparison with extant European brown bears, Ursus arctos, in terms of gross-wear features on the teeth, suggests that tubers were absent from the cave bear diet and not responsible for the extreme wear seen in cave bear teeth (Pinto Llona 2006). Dental Microwear Analysis (DMA), comparing diet-related microscopic dental wear features of brown bears, whose diet is known, with cave bears suggests that the cave bear dietary behavior included a greater consumption of bone versus that of brown bears. Results obtained on the stable isotopic yield of cave bear bones also are interpreted as indicators of a largely vegetarian diet, and one even more vegetarian than contemporary herbivorous taxa (Bocherens et al. 1994; Pinto Llona 2006). The bones of central and western European cave bears matched those of vegetarians in having low levels of nitrogen-15, which is accumulated by meat eaters. However, several cave bear sites in the Peştera cu Oase in the southwestern tip of the Carpathian mountains have shown that the cave bears of that region may have been largely carnivorous, due to higher levels of nitrogen-15 in their bones (Choi 2008). Nitrogen-15 is accumulated by animals and, thus, carnivores, which eat animals, accumulate more nitrogen-15 in their bodies than do herbivores. Carnivorous behavior is also evident from very large cave bear tooth marks on young cave bear skulls in Yarimburgaz Cave in western Turkey (Choi 2008). Taphonomic analysis of modifications on cave bear bones produced by carnivores suggests that in addition to their herbivorous and carnivorous behaviors, cave bears actively scavenged on the carcasses of their con-specifics (Pinto Llona 2006). It is possible that different populations of cave bears had different dietary habits, including possible bear-bear cannibalism (Choi 2008) and cannibalistic scavenging behavior. In the case of the central and western European populations, whose bones lacked an identifiable isotopic signature of nitrogen-15, it is possible that cannibalistic scavenging behavior may have been quite limited, relative to the more dominant vegetarian diet, leaving no trace (Pinto Llona 2006). Cave bear longevity is unknown, though it has been estimated that they seldom exceeded 20 years of age (Bieder 2005). Some cave bear bones show signs of numerous different ailments, including fusion of the spine, bone tumors, cavities, tooth resorption, necrosis (particularly in younger specimens), nematodes, osteomyelitis, periostitis, rickets, and kidney stones (Brown 1993). Male cave bear skeletons have been found with broken baculums, probably due to fighting during breeding season (Bjorn 1968). Death during hibernation is considered to have been a common end for cave bears, mainly befalling specimens that failed ecologically during the summer season through inexperience, sickness, or old age (Bjorn 1968). Paleontologists doubt adult cave bears had any natural predators, save for pack hunting wolves and cave hyenas, which would probably have attacked sick or infirm specimens (Bieder 2005). Cave hyenas are thought to be responsible for the dis-articulation and destruction of some cave bear skeletons. Such large carcasses would have been an optimal food resource for the hyenas, especially at the end of the winter, when food was scarce (Diedrich and Zak 2006).
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Post by Deleted on Oct 3, 2018 4:26:37 GMT -5
This might sound like a dumb question but was the cave bear a brown bear?
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Post by brobear on Oct 3, 2018 4:41:11 GMT -5
This might sound like a dumb question but was the cave bear a brown bear? No, but closely related. Both the cave bear and the brown bears evolved directly from the etruscan bear during the Pleistocene. It has recently been discovered ( I posted it here somewhere ) that brown bears and cave bears did sometimes interbreed in Ice Age Europe. Today's brown bears have some cave bear DNA.
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Post by Deleted on Oct 3, 2018 4:43:47 GMT -5
This might sound like a dumb question but was the cave bear a brown bear? No, but closely related. Both the cave bear and the brown bears evolved directly from the etruscan bear during the Pleistocene. It has recently been discovered ( I posted it here somewhere ) that brown bears and cave bears did sometimes interbreed in Ice Age Europe. Today's brown bears have some cave bear DNA. Oh ok so the cave bear was a different species but still related close enough to breed with brown bears. Ok I got it.
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Post by King Kodiak on Oct 17, 2018 5:00:04 GMT -5
www.sciencedaily.com/releases/2018/07/180728083510.htmExtinct vegetarian cave bear diet mystery unravelled During the Late Pleistocene period (between 125,000 to 12,000 years ago) two bear species roamed Europe: omnivorous brown bears (Ursus arctos) and the extinct mostly vegetarian cave bear (Ursus spelaeus). Until now, very little is known about the dietary evolution of the cave bear and how it became a vegetarian, as the fossils of the direct ancestor, the Deninger's bear (Ursus deningeri), are extremely scarce. However, a paper published in the journal Historical Biology, sheds new light on this. A research team from Germany and Spain found that Deninger's bear likely had a similar diet to its descendant -- the classic cave bear -- as new analysis shows a distinct morphology in the cranium, mandible and teeth, which has been related to its dietary specialization of a larger consumption of vegetal matter. To understand the evolution of the cave bear lineage, the researchers micro-CT scanned the rare fossils and digitally removed the sediments so as not to risk damaging the fossils. Using sophisticated statistical methods, called geometric morphometrics, the researchers compared the three-dimensional shape of the mandibles and skull of Deninger's bear with that of classic cave bears and modern bears. "The analyses showed that Deninger's bear had very similarly shaped mandibles and skull to the classic cave bear," explains Anneke van Heteren, lead-author of the study and Head of the Mammalogy section at the Bavarian State Collection of Zoology. This implies that they were adapted to the same food types and were primarily vegetarian. "There is an ongoing discussion on the extent to which the classic cave bear was a vegetarian. And, this is especially why the new information on the diet of its direct ancestor is so important, because it teaches us that a differentiation between the diet of cave bears and brown bears was already established by 500 thousand years ago and likely earlier," says Mikel Arlegi, doctoral candidate at the Universities of the Basque Country and Bordeaux and co-author of the study. Interestingly, researchers also found there are shape differences between the Deninger's bears from the Iberian Peninsula and those from the rest of Europe, which are unlikely to be related to diet. They have come up with three possibilities to explain these differences: 1) the Iberian bears are chronologically younger than the rest, 2) the Pyrenees, acting as natural barrier, resulted in some genetic differentiation between the Iberian bears and those from the rest of Europe, 3) there were multiple lineages, with either just one leading to the classic cave bear, or each lineage leading to a different group of cave bears. "However, more fossils are necessary to test these three hypotheses," Asier Gómez-Olivencia, Ikerbasque Researcher at the University of the Basque Country said.
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