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Post by King Kodiak on Mar 23, 2020 6:48:11 GMT -5
Correct answer on topic "Cave Bear Evolution" Reply #36 - Ursus spelaeus spelaeus. Correct. Ursus Spelaeus Spelaeus would be the exact scientific name.
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Post by brobear on Apr 20, 2020 5:31:39 GMT -5
www.ncbi.nlm.nih.gov/pmc/articles/PMC5059403/ Retreat and extinction of the Late Pleistocene cave bear (Ursus spelaeus sensu lato) The cave bear (Ursus spelaeus sensu lato) is a typical representative of Pleistocene megafauna which became extinct at the end of the Last Glacial. Detailed knowledge of cave bear extinction could explain this spectacular ecological transformation. The paper provides a report on the youngest remains of the cave bear dated to 20,930 ± 140 14C years before present (BP). Ancient DNA analyses proved its affiliation to the Ursus ingressus haplotype. Using this record and 205 other dates, we determined, following eight approaches, the extinction time of this mammal at 26,100–24,300 cal. years BP. The time is only slightly earlier, i.e. 27,000–26,100 cal. years BP, when young dates without associated collagen data are excluded. The demise of cave bear falls within the coldest phase of the last glacial period, Greenland Stadial 3. This finding and the significant decrease in the cave bear records with cooling indicate that the drastic climatic changes were responsible for its extinction. Climate deterioration lowered vegetation productivity, on which the cave bear strongly depended as a strict herbivore. The distribution of the last cave bear records in Europe suggests that this animal was vanishing by fragmentation into subpopulations occupying small habitats. One of them was the Kraków-Częstochowa Upland in Poland, where we discovered the latest record of the cave bear and also two other, younger than 25,000 14C years BP. The relatively long survival of this bear in karst regions may result from suitable microclimate and continuous access to water provided by deep aquifers, indicating a refugial role of such regions in the Pleistocene for many species. The extinction of large-bodied mammals (called megafauna) is one of the most characteristic and inherent features of the Late Pleistocene. The disappearance began 50,000 years ago and affected a substantial number of mammalian genera, e.g. 36 % of them in Eurasia, 72 % in North America and 83 % in South America (Barnosky et al. 2004). Both the climate and environment changes, as well as human influence, are believed to be the main causes of this extinction (Barnosky et al. 2004; Cooper et al. 2015; Koch and Barnosky 2006; Lorenzen et al. 2011; Stuart 2015). The climate shift was sufficient to explain the fauna transformation in some cases, but in others, a combination of climatic and anthropogenic effects was most probably responsible for this phenomenon (Cooper et al. 2015; Lorenzen et al. 2011). A typical representative of megafauna is the cave bear (Ursus spelaeus sensu lato), which was one of the most widespread mammals in Eurasia in the Late Pleistocene. It evolved from Middle Pleistocene Ursus deningeri and developed into several forms which can be distinguished at morphological and genetic levels. Two main European forms in the species rank, which diverged probably between 414,000 and 173,000 years ago, were identified as Ursus ingressus, which inhabited south-eastern and central Europe as well as the Ural (Baca et al. 2014; Rabeder et al. 2004b), and U. spelaeus, which lived mainly in western Europe, although its remains were found also in the Altai (Knapp et al. 2009; Rabeder et al. 2004b). According to the rules of the International Code of Zoological Nomenclature, U. ingressus should, however, be called Ursus kanivetz, because under the latter name a bear from Medvezhiya Cave in the Ural was first described by Vereshchagin (1973) (see also Baryshnikov and Puzachenko (2011)). Further studies of ancient DNA showed that the haplotype from Medvezhiya Cave is clustered with others from Europe, described as U. ingressus (Baca et al. 2012; Knapp et al. 2009). Additionally, two small cave bear forms that had preserved some primitive traits were distinguished as subspecies of U. spelaeus: U. spelaeus eremus and U. spelaeus ladinicus (Rabeder and Hofreiter 2004; Rabeder et al. 2004a). Their distribution was confined to the high alpine caves in Austria and Italy. Recently, another major group of large cave bears from the Caucasus and the Yana River region in eastern Siberia was discovered (Baryshnikov 1998; Knapp et al. 2009). Initially, they were named Ursus deningeri kudarensis, but recent genetic studies suggest that they should be considered a third species, U rsus kudarensis (Stiller et al. 2014). By the end of the Pleistocene, all these cave bear forms were extinct and the causes and timing of this process have been debated over the recent years. Direct radiocarbon dating indicates that the last cave bears became extinct prior to the Last Glacial Maximum (LGM) and disappeared from fossil record quite simultaneously in different parts of Europe about 24,000 14C years before present (BP) (about 28,000 cal. years BP) (Bocherens et al. 2014; Hofreiter et al. 2002; Martini et al. 2014; Pacher and Stuart 2009; Sabol et al. 2014; Wojtal et al. 2015). Paleogenetic analyses showed, nonetheless, that the demise of cave bears started ca. 50,000 radiocarbon years BP (Stiller et al. 2010), thus about 25,000 years before their final extinction. It has been argued that apart from the changing climate (Pacher and Stuart 2009; Stuart and Lister 2007), several other factors contributed to the decline of cave bears. There is compelling evidence for human hunting of cave bears (Münzel et al. 2011; Wojtal et al. 2015), as well as their competition for caves as a shelter (Grayson and Delpech 2003). Possibly, also large carnivores like cave lion (Panthera spelaea) and cave hyena (Crocuta crocuta spelaea) hunted cave bears while these were hibernating (Bocherens et al. 2011a; Diedrich 2014). The paper reports on, so far, the youngest remains of the cave bear from the Stajnia Cave located in the Częstochowa Upland, Poland. In this region were also found other quite young fossils of this bear in two caves, Komarowa and Deszczowa (Nadachowski et al. 2009; Wojtal 2007; Wojtal et al. 2015). Genetic analyses confirmed beyond doubt the affiliation of this specimen to the cave bear, whereas the direct radiocarbon dating provided the evidence for the survival of this species into the Greenland stadial GS-3. Using this new dating and more than 200 published dates, we estimated the time of cave bear extinction and discussed potential factors of its disappearance and survival in karst regions.
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Post by King Kodiak on Apr 28, 2020 7:32:06 GMT -5
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Post by King Kodiak on May 26, 2020 10:26:59 GMT -5
European Cave Bears Had Pure Herbivorous Diet
May 26, 2020 by Natali Anderson
An isotopic analysis of fossil collagen from the bones collected in three Romanian caves indicates that the cave bear (Ursus spelaeus), an extinct species of bear that lived 300,000-25,000 years ago in Europe, the Mediterranean and Asia, was exclusively herbivorous.
The cave bear was a very large type of bear that formed the sister lineage of living brown bears and polar bears.
The animal lived during the Pleistocene epoch and became extinct approximately 25,000 years ago.
It was 2.7-3.5 m (8.9-11.5 feet) long and up to 1.7 m (5.6 feet) at the shoulder, and has a mass between 225 and 500 kg.
Dietary habits of the cave bear has widely been debated as different paleobiological studies produced different dietary inferences for the animal, ranging from carnivory to pure herbivory.
“It comes as big surprise that these animals — despite their size and the fact they lived in a cold and dry environment — exclusively subsisted on plants,” said senior author Professor Herve Bocherens, a researcher in the Senckenberg Center for Human Evolution and Palaeoenvironment and the Department of Geosciences, Biogeology at the University of Tübingen.
“While this vegetarian lifestyle has already been proven for the vast majority of cave bears in Europe, fossil discoveries from Romania gave rise to a lively scientific discussion as to whether cave bears in that region may also have fed on meat.”
For the study, Professor Bocherens and colleagues used 20,000 to 49,000-year-old skeletal remains of six adult cave bears from the three Romanian cave sites: Măgura, Cioclovina and Răsuflătoarei.
“Well-preserved bone specimens of cave bears from these three sites allowed us to examine the feeding behavior of the individuals from this region,” the researchers said.
They analyzed the nitrogen isotope values of amino acids in the bone collagen from the cave bear specimens.
“We measured special amino acids in the fossil bone collagen and subsequently compared the values with those from other cave bear bones as well as typical carnivores and herbivores; in our case, a lion and a horse,” Professor Bocherens added.
“Our results show that Romanian cave bears subsisted on an exclusively vegetarian diet before they became extinct about 25,000 years ago.”
The study was published in the journal Scientific Reports.
www.sci-news.com/paleontology/herbivorous-cave-bears-08466.html
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Post by King Kodiak on Sept 12, 2020 10:37:28 GMT -5
FIRST EVER PRESERVED GROWN UP CAVE BEAR-EVEN ITS NOSE IS INTACT-UNHEARTHED ON THE ARTIC ISLAND
Separately at least one preserved carcass of a cave bear cub found on the mainland of Yakutia, with scientists hopeful of obtaining its DNA.
More details of the finds are to be announced soon.
Until now only the bones of cave bears have been discovered.
The new finds are of ‘world importance’, according to one of Russia’s leading experts on extinct Ice Age species.
Scientist Lena Grigorieva said of the island discovery of the adult beast: 'Today this is the first and only find of its kind - a whole bear carcass with soft tissues.
'It is completely preserved, with all internal organs in place including even its nose.
“Previously, only skulls and bones were found. This find is of great importance for the whole world.’
First ever preserved grown up cave bear - even its nose is intact - unearthed on Bolshoy Lyakhovsky island, with at least one preserved carcass of a cave bear cub found on the mainland of Yakutia. Pictures: NEFU
The remains were found by reindeer herders on the island and the remains will be analysed by scientists at the North-Eastern Federal University (NEFU) in Yakutsk, which is at the forefront of research into extinct woolly mammoths and rhinos.
Russian and foreign colleagues will be invited to join the study.
The cave bear (Ursus spelaeus) is a prehistoric species or subspecies that lived in Eurasia in the Middle and Late Pleistocene period and became extinct about 15,000 years ago.
According to the rough preliminary suggestions the bear could live in Karginsky interglacial (this was the period between 22,000 and 39,500 years).
'It is necessary to carry out radiocarbon analysis to determine the precise age of the bear,’ said senior researcher Maxim Cheprasov from the Mammoth Museum laboratory in Yakutsk.
The finder transferred the right to research to the scientists of NEFU, he said.
Bolshoy Lyakhovsky Island, or Great Lyakhovsky, is the largest of the Lyakhovsky Islands belonging to the New Siberian Islands archipelago between the Laptev Sea and the East Siberian Sea in northern Russia. Picture: Alexander Oboimov
'A scientific programme for its comprehensive study will be prepared. We will have to study the carcass of a bear using all modern scientific research methods - molecular genetic, cellular, microbiological and others.
'The research is planned on as large a scale as in the study of the famous Malolyakhovsky mammoth,’ said Dr Grigorieva, leading researcher of the International Centre for Collective Use of Molecular Paleontology at the NEFU’s Institute of Applied Ecology of the North.
Recent years have seen major discoveries of mammoths, woolly rhinos, Ice Age foal, several puppies and Cave Lion cubs as the permafrost melts in Siberia.
Lena Grigorieva, first from the left, leading researcher of the International Centre for Collective Use of Molecular Paleontology at the NEFU’s Institute of Applied Ecology of the North
siberiantimes.com/other/others/news/first-ever-preserved-grown-up-cave-bear-even-its-nose-is-intact-unearthed-on-the-arctic-island/
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Post by brobear on Sept 12, 2020 10:49:28 GMT -5
That is some big news; just out today: By Anna Liesowska12 September 2020 ( Nice find ). This probably means more cave bear DNA. ( Although I'm no longer believing that scientists will ever clone any prehistoric animals. I'm tired of holding my breath ).
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Post by King Kodiak on Sept 12, 2020 11:07:16 GMT -5
Yes it is some big news, not everyday we get new news about prehistoric animals.
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Post by brobear on Sept 17, 2020 8:36:24 GMT -5
Quote from reply #55: It was 2.7-3.5 m (8.9-11.5 feet) long and up to 1.7 m (5.6 feet) at the shoulder, and has a mass between 225 and 500 kg. 5 feet 6 inches high at the shoulders ( bigger than any Kodiak bear ). Estimated perhaps 500 kg ( 1,100 pounds ). Perhaps 11 feet 6 inches from nose to rump.
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Post by OldGreenGrolar on Sept 17, 2020 9:03:17 GMT -5
Reply 56. It seems the cave bear has entered polar bear territory. It seems the two might have met up with the ancestors of the polar bears which looked more like brown bears.
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Post by brobear on Sept 17, 2020 10:59:36 GMT -5
Yakutia map:
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Post by brobear on Sept 17, 2020 11:02:21 GMT -5
Reply 56. It seems the cave bear has entered polar bear territory. It seems the two might have met up with the ancestors of the polar bears which looked more like brown bears. Whever the cave bear traveled, there had to be enough vegetation to sustain him.
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Post by brobear on Jan 11, 2021 2:13:23 GMT -5
I recognize this picture. I put this model together and painted it when I was a kid. Googled it: Vintage AURORA Cave Bear Prehistoric Dinosaur scene 1972 ( I was a 24 year old kid )
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Post by brobear on Jan 28, 2021 10:11:12 GMT -5
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Post by OldGreenGrolar on Feb 1, 2021 7:22:41 GMT -5
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Post by King Kodiak on Feb 1, 2021 10:42:05 GMT -5
Reply #52: good video Green.
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Post by brobear on Feb 18, 2021 17:42:23 GMT -5
journals.plos.org/plosone/article?id=10.1371/journal.pone.0206791 Palaeohistology and life history evolution in cave bears, Ursus spelaeus sensu lato Abstract The abundance of skeletal remains of cave bears in Pleistocene deposits can offer crucial information on the biology and life history of this megafaunal element. The histological study of 62 femora from 23 different European localities and comparisons with specimens of five extant ursid species revealed novel data on tissue types and growth patterns. Cave bear’s femoral bone microstructure is characterized by a fibrolamellar complex with increasing amounts of parallel-fibered and lamellar bone towards the outer cortex. Remodelling of the primary bone tissue initially occurs close to the perimedullary margin of the bone cortex around the linea aspera. Although similar histological traits can be observed in many extant bear species, the composition of the fibrolamellar complex can vary greatly. Cave bears reached skeletal maturity between the ages of 10 and 14, which is late compared to other bear species. There is a significant correlation between altitude and growth, which reflects the different body sizes of cave bears from different altitudes.
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Post by OldGreenGrolar on Feb 19, 2021 8:33:52 GMT -5
/\ Brobear, thanks for this additional information. I believe that cave bears average weight would be heavier than even polar bears from Foxe Basin if we include only these between 11 to 14 years olds as the average weight.
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Post by brobear on Mar 3, 2021 9:52:52 GMT -5
The last cave bear by Ville Sinkkonen
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Post by King Kodiak on Mar 3, 2021 11:22:36 GMT -5
Reply #56: you sure that's a cave bear? That does not look like the typical cave bear representation.
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Post by brobear on Mar 3, 2021 23:55:52 GMT -5
Reply #56: you sure that's a cave bear? That does not look like the typical cave bear representation. I believe that the artist, Ville Sinkkonen, is simply depicting a cave bear as being a typical member of the bear family and not a prehistoric monster. In reality, I doubt that it would have always been easy to distinguish a cave bear from a brown bear - depending on individuals.
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