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Post by brobear on Jan 18, 2018 20:23:11 GMT -5
www.ebay.com/itm/Pleistocene-Black-Bear-Jaw-with-teeth-Ultra-Rare-/263344686686 The ancestors of American black bears and Asiatic black bears diverged from sun bears 4.58 mya. The American black bear then split from the Asian black bear 4.08 mya. The earliest American black bear fossils, which were located in Port Kennedy, Pennsylvania, greatly resemble the Asiatic species, though later specimens grew to sizes comparable to grizzlies. From the Holocene to present, American black bears seem to have shrunk in size, American and Asian black bears are considered sister taxa, and are more closely related to each other than to other species of bear. According to recent studies, the sun bear is also a relatively recent split from this lineage.A small primitive bear called Ursus abstrusus is the oldest known North American fossil member of the genus Ursus, dated to 4.95 mya. This suggests that U. abstrusus may be the direct ancestor of the American black bear, which evolved in North America. Although Wolverton and Lyman still consider U. vitabilis an "apparent precursor to modern black bears", it has also been placed within U. americanus.
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Post by brobear on Oct 17, 2018 2:29:40 GMT -5
www.revolvy.com/topic/Ursus%20etruscus Some scientists have proposed that the early, small variety of U. etruscus of the middle Villafranchian era survives in the form of the modern Asian black bear.
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Post by brobear on Apr 30, 2019 4:47:44 GMT -5
markgelbart.wordpress.com/tag/pleistocene-black-bear-evolution/ Black Bear (Ursus americanus) Diversity during the Pleistocene December 19, 2016 Fossil evidence suggests North American black bears evolved from an Holarctic population of bears about 3 million years ago. The founding preceding species is known as Ursus abstrusus in North America and Ursus minimus in Eurasia but they were likely the same animal. Eurasian black bears ( Ursus thibetanus ) diverged from North American black bears during some climate phase when the ancestral populations became geographically isolated. Before this divergence moderate climate allowed forested conditions to exist across the Bering land bridge. But deteriorating climate transformed the land bridge to tundra when it wasn’t submerged under the Bering Sea. Genetic evidence indicates western populations of North American black bears diverged from their eastern counterparts about 1.8 million years ago. This corresponds with the beginning of the Pleistocene. Although weak Ice Ages occurred during the preceding Pliocene, they became much more severe at the onset of the Pleistocene. Glaciers covered most of Canada and the upper elevations of the Rocky Mountains, blocking gene flow between eastern and western populations of black bears. Some mixing occurred (and is presently occurring) during interglacials, but because glacial climate phases are 5-10 times longer than most interglacials, isolation between eastern and western populations has been the norm. *More reading on site. 
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Post by brobear on Apr 30, 2019 4:52:50 GMT -5
www.ncbi.nlm.nih.gov/pubmed/9364767 Phylogeography and pleistocene evolution in the North American black bear. To determine the extent of phylogeographic structuring in North American black bear (Ursus americanus) populations, we examined mitochondrial DNA sequences (n = 118) and restriction fragment length polymorphism profiles (n = 258) in individuals from 16 localities. Among the bears examined, 19 lineages falling into two highly divergent clades were identified. The clades differ at 5.0% of nucleotide positions, a distance consistent with an origin 1.8 MYA, and have different but overlapping geographical distributions. Areas of clade cooccurrence show that eastern and western populations are currently mixing, but regional differences in lineage distribution suggest that mixing has begun only recently. The long-term population history of black bears appears to be characterized predominantly by long-term regional isolation followed by recent contact and hybridization. Congruence between the pattern of diversity observed in black bears and patterns of forest refuge formation during the Pleistocene supports earlier speculation that Pleistocene forest fragmentations underlie a common pattern in the phylogeography of North American forest taxa.
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Post by King Kodiak on Apr 30, 2019 16:02:47 GMT -5
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Post by OldGreenGrolar on Nov 15, 2019 1:46:58 GMT -5
The Etruscan bear might be a plastocene Asiatic black bear?
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Post by brobear on Nov 15, 2019 3:00:10 GMT -5
The Etruscan bear might be a plastocene Asiatic black bear? The Asiatic black bear ( Ursus thibetanus ) and the Etruscan bear ( Ursus etruscus ) just might be one-and-the-same bear. -Here is one source: en.wikipedia.org/wiki/Ursus_etruscus Quote: Some scientists have proposed that the early, small variety of U. etruscus of the middle Villafranchian era survives in the form of the modern Asian black bear. bearsoftheworld.net/ursus_etruscus.asp Quote: The Etruscus was similar in size and anatomical to the Asiatic black bear of today. In fact, it has been suggested by some scientists that the early, small variety of Ursus etruscus of the middle Villafranchian era (1.9 to 1.8 million years ago) survives in the form of the modern Asian black bear. However, the Etruscus bear eventually became the size of today's European brown bear. *In other words, our Asiatic black bears might be a surviving population of the Etruscan bears. This would make our Asiatic black bears not only the first cousin to our American black bears but also the granddaddy of the brown bears and the polar bear ( also the cave bears ).  ! |
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Post by King Kodiak on Nov 20, 2019 7:13:42 GMT -5
The Pleistocene black bear (Ursus thibetanus) from the Urals (Russia)... The fossil record of U. thibetanus is widely known in the middle and late Pleistocene of Europe, Cau- casus, Ural, southern part of Siberia, China, and Japan Islands (Erdbrink 1953;Kurtén 1968;CrégutBonnoure 1997;Baryshnikov 2002Baryshnikov , 2010. It is not quite clear if this species was constantly distributed throughout this vast range or came to Europe only from time to time. ... ... Mazza and Rustioni (1994) suggested that a frac- tion of the ursid material from the locality Perpignan (Chefdebien) in France (MN15a) belongs to U. thi- betanus. This opinion was also accepted by Baryshnikov (2002Baryshnikov ( , 2007. Other researchers believe, on the contrary, that this Perpignan bear does not belong to U. thibetanus and should be referred to U. minimus (Morlo and Kundrat 2001;Wagner 2010). ... ... Mokhnevskaya Cave (=Makhnevskaya Ice Cave) is lo- cated in the Alexandrovskii District of Perm Province in Russia (N 59°26´, E 57°41´). A small porcupine has been excavated together with various Pleistocene mammal spe- cies: Canis lupus, Ursus thibetanus permjak, Panthera spelaea, Mammuthus primigenius, Equus ferus, Cervus ela- phus, Alces alces, and Bison priscus (Baryshnikov, 2001;Kosintsev & Podoprigora, 2003). Stratigraphic position of the locality is vague. ... ... This opinion may be reinforced by the remarkable coincidence of the Pleistocene distribution of H. brachyu- ra vinogradovi in Europe and east Mediterranean re- gion with that of the Asian black bear Ursus thibetanus G. Cuvier. The both taxa were found together in Kudaro caves in Caucasus and in Mokhnevskaya Cave in Ural Mountains ( Baryshnikov, 2001). Presumably, H. brachyura and U. thibetanus inhabiting now forests of South-Eastern Asia simultaneously penetrated to Eu- rope during warm stages of the Pleistocene. ... . Ma ( Qiu 2006), was referred to the lion group of pantherine cats ( Pei 1934;Harington 1969). Numerous finds of fossil lions in Asian Russia are known from the papers by Riabinin (1919), Gromova (1932), Vangengeim (1961), Vereshchagin (1971), Alexeeva (1980), Foronova (1982, 1999, 2001), Baryshnikov and Boeskorov (2001), Sotnikova and Nikolskiy (2006), Baryshnikov and Petrova (2008) and Ovodov and Tarasov (2009). However, the material presented in these works mainly belongs to the Late Pleistocene Panthera (Leo) spelaea (Goldfuss, 1810). ... ... As noted above, there are few reports indicating the Early or Middle Pleistocene occurrence of fossil lions in Asian Russia. A skull of a giant pantherine cat (with condylobasal length [CBL] = 422 mm and zygomatic breadth [ZB] = 312 mm) was found together with Hystrix vinogradovi Argyropolo, 1941 andUrsus thibetanus permjak Baryshnikov, 2001 in the Mokhnevskaya Cave, Middle Ural Mountains, in the deposits correlated with a warm stage of the late Middle Pleistocene (MIS 7) or the last interglacial (MIS 5e) ( Baryshnikov 2001Baryshnikov , 2003). Unfortunately, the skull was not available for detailed study, as it is part of a private collection. ... During the Toringian, this species was present in many European localities (for reviews see, e.g., Baryshnikov 1992, 2007, 2010, Rustioni and Mazza 1993, Crégut-Bonnoure 1996, 1997, Turner 2000). In the present paper, we follow Baryshnikov (2010) who accepts only one valid taxon (U. t. mediterraneus) for all European and Caucasian fi nds of U. thibetanus (with the exception of U. t. permjak BARYSHNIKOV, 2002 from the Ural Mountains-see Baryshnikov (2002Baryshnikov ( , 2007) for details), but other authors recognize more taxa (e.g., Crégut-Bonnoure 1997). Based on the present revision, Šandalja I locality can be added to the European localities with an unambiguous record of Asiatic black bear. ... . The loss of habitats (most probably caused by palaeoenvironmental changes) is closely related to the process of extinction. It is known that the porcupine (Hystrix brachyura vinogradovi) occupied the Urals and Altai Mountains of Siberia in the Late Pleistocene, and the northern limit for habitats of fossil porcupine was almost at 60 N (Baryshnikov, 2001Baryshnikov, , 2003). The Altai Pleistocene porcupines occurred approximately 950 km north of today's habitat boundary for Malayan porcupine. ... rustioni & Mazza 1993a). throughout this period they were recorded from the urals (Baryšnikov 2002a) and the caucasus region (Baryšnikov 2010) across central (von reichenau 1906, Sieber 1949, nagel & rabeder 2000, turner 2000, Musil 2005) and southern Europe (thenius 1958, Kurtén & Poulianos 1977) to Spain (torres 1988 ) and France (Bonnoure 1996), but not from Great Britain. these bears represent the last migration event of black bears into Europe and belong to Ursus thibetanus cuvier, 1823 (e.g. ... www.researchgate.net/publication/291773048_The_Pleistocene_black_bear_Ursus_thibetanus_from_the_Urals_Russia |
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Post by King Kodiak on Jan 23, 2020 17:46:15 GMT -5
The first finding of Asian black bear (Carnivora, Ursidae, Ursus (Euarctos) thibetanus G. Cuvier, 1823) in the Late Pleistocene of northern Eurasia An M1 tooth of Asian black bear (Ursus (Euarctos) thibetanus G. Cuvier, 1823) was found in deposits of the Tetyukhinskaya cave (Middle Sikhote-Alin, 44°35′N, 135°36′E). This finding is the first reliable evidence of Asian black bear’s presence in Pleistocene of Primorye. Its morphological and morphometric descriptions are given. The period of inhabitation of U. (E.) thibetanus determined based on the radiocarbon date obtained during the study of the tooth, is 39 874 ± 133 BP (NSK-850, UGAMS-21786), which corresponds to the middle of Marine Isotope Stage 3 (MIS 3) of Late Pleistocene. The composition of ancient theriofauna indicates the existence of wide variety of landscapes in Primorye in the middle of Late Pleistocene. A refugium of forest fauna, in which species of taiga, nemoral, and Central Asian mountain–forest theriocomplexes were present, was located in southern Primorye in Late Pleistocene. Full report here: www.researchgate.net/publication/312263226_The_first_finding_of_Asian_black_bear_Carnivora_Ursidae_Ursus_Euarctos_thibetanus_G_Cuvier_1823_in_the_Late_Pleistocene_of_northern_Eurasia |
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Post by brobear on Mar 2, 2020 3:55:55 GMT -5
www.iucnredlist.org/species/22824/114252336#geographic-range Asiatic Black Bear - Ursus thibetanus Garshelis, D. & Steinmetz, R. 2016. Ursus thibetanus (errata version published in 2017). The IUCN Red List of Threatened Species 2016: e.T22824A114252336. dx.doi.org/10.2305/IUCN.UK.2016-3.RLTS.T22824A45034242.en. Downloaded on 02 March 2020. Geographic Range - Extant: Afghanistan; Bangladesh; Bhutan; Cambodia; China; India; Iran, Islamic Republic of; Japan; Korea, Democratic People's Republic of; Korea, Republic of; Lao People's Democratic Republic; Myanmar; Nepal; Pakistan; Russian Federation; Taiwan, Province of China; Thailand; Viet Nam RANGE DESCRIPTION Fossil remains of the Asiatic Black Bear have been found in various sites in Europe, as far north as the Ural Mountains and Germany and west to France, dating from the early Pliocene to late Pleistocene (Erdbrink 1953, Kosintsev 2007, Baryshnikov and Zakharov 2013, Fourvel et al. 2014); however, in historic times the species has been limited to Asia. The western range limit is in southeastern Iran, inhabited by the so-called Baluchistan bear (U. t. gedrosianus) (Ahmadzadeh et al. 2008, Ghadirian et al. 2012). This small population is likely connected to the Baluchistan bear population in southern Pakistan. Disjunct populations of Asiatic Black Bears also occur in the more mountainous regions of northern Pakistan (Khan et al. 2012) and Afghanistan (Ostrowski et al. 2009). Eastward they continue within a narrow band along the foothills and south side of the Himalayas (up to treeline) across India, Nepal, and Bhutan, and then more widely distributed at lower elevations (generally >70 m but occasionally to 20 m) in the hill states of northeastern India (Sathyakumar and Choudhury 2007). They occur across mainland Southeast Asia, stretching south in Myanmar and Thailand to ~200 km north of the Malaysian border (Kanchanasakha et al. 2010); there are no records of Asiatic Black Bears ever existing in Malaysia. Over half the total range area of this species exists in China, especially in the south-central and southwestern parts of the country. This distribution includes portions of Tibet, from which the specific name, thibetanus, is derived. Smaller, remnant populations occur in eastern China. Another population cluster exists in northeastern China, the southern Russian Far East, and North Korea. A small isolated population exists in southern South Korea. They also live on the southern islands of Japan (Honshu and Shikoku) and on Taiwan and Hainan. Although they have been extirpated from large portions of their range, they remain in all 18 historic range countries. The distribution of the Asiatic Black Bear roughly coincides with forest distribution in southern and eastern Asia (FAO 2010), except that in central and southern India this species is replaced by the Sloth Bear (Melursus ursinus), in Malaysia it is replaced by the Sun Bear and north and west of the Russian Far East it is replaced by the Brown Bear (Ursus arctos). However, the Asiatic Black Bear overlaps the ranges of each of these species, especially the Sun Bear in a large portion of Southeast Asia and small portions of northeast India. It also greatly overlaps the range of Giant Pandas (Ailuropoda melanoleuca) in south-central China. In Afghanistan, Pakistan, and India, the Asiatic Black Bear range overlaps the Brown Bear (at elevations >3,000 m) in the Himalayas (but curiously, does not appear to overlap Brown Bears in Nepal (A. Aryal, Massey University, New Zealand, pers. comm, 2016; Bista and Aryal 2013). It also overlaps Brown Bears in south-central and northeastern China, North Korea, and the Russian Far East. In India, Asiatic Black Bear range overlaps the Sloth Bear at low elevations (<1,000 m) in some protected areas including Corbett Tiger Reserve and Rajaji National Parks, Uttarakhand (Bargali 2012). However, there is no evidence of overlap with Sloth Bears in neighbouring Nepal (Garshelis et al. 1999). In North Karbi Anglong wildlife sanctuary in Assam, northeast India, Asiatic Black Bear range overlaps both Sloth Bears and Sun Bears—one of the few places in the world where all three of these species coexist, although all are reported to be rare (Choudhury 2011, Choudhury and Chand 2012). 
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Post by King Kodiak on Mar 2, 2020 6:27:58 GMT -5
It is still unclear if the Asiatic black bear was ever in Europe. Some researchers think that those bears were actually Ursus minimus. Remember that the skeletons of both bears are very similar And it is very difficult to distinguish them one from the other.
. Mazza and Rustioni (1994) suggested that a frac- tion of the ursid material from the locality Perpignan (Chefdebien) in France (MN15a) belongs to U. thi- betanus. This opinion was also accepted by Baryshnikov (2002Baryshnikov ( , 2007. Other researchers believe, on the contrary, that this Perpignan bear does not belong to U. thibetanus and should be referred to U. minimus (Morlo and Kundrat 2001;Wagner 2010). ...
www.researchgate.net/publication/291773048_The_Pleistocene_black_bear_Ursus_thibetanus_from_the_Urals_Russia
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Post by brobear on Mar 2, 2020 6:35:42 GMT -5
It is still unclear if the Asiatic black bear was ever in Europe. Some researchers think that those bears were actually Ursus minimus. Remember that the skeletons of both bears are very similar And it is very difficult to distinguish them one from the other.
. Mazza and Rustioni (1994) suggested that a frac- tion of the ursid material from the locality Perpignan (Chefdebien) in France (MN15a) belongs to U. thi- betanus. This opinion was also accepted by Baryshnikov (2002Baryshnikov ( , 2007. Other researchers believe, on the contrary, that this Perpignan bear does not belong to U. thibetanus and should be referred to U. minimus (Morlo and Kundrat 2001;Wagner 2010). ...
www.researchgate.net/publication/291773048_The_Pleistocene_black_bear_Ursus_thibetanus_from_the_Urals_Russia That thought did run through my mind, although I was thinking Etruscan Bear. |
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Post by King Kodiak on Mar 2, 2020 6:47:24 GMT -5
Well remember that Ursus etruscus came from Ursus minimus.
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Post by brobear on Mar 2, 2020 6:59:08 GMT -5
Well remember that Ursus etruscus came from Ursus minimus. True, and both were similar to the Asiatic black bear. Some biologists think that *maybe the Asiatic black bear and the Etruscan bear are one-and-the-same-bear. |
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Post by King Kodiak on Mar 2, 2020 7:10:30 GMT -5
Well remember that Ursus etruscus came from Ursus minimus. True, and both were similar to the Asiatic black bear. Some biologists think that *maybe the Asiatic black bear and the Etruscan bear are one-and-the-same-bear. |
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Post by brobear on Apr 29, 2020 7:05:59 GMT -5
markgelbart.wordpress.com/2011/03/10/pleistocene-bears-of-southeastern-north-america/ Ursus abstruscus is the probable evolutionary ancestor of American and Asian black bears which once consisted of a geographically continuous population. Glacial ice separated the two populations at the beginning of the Pleistocene, resulting in two different species. Bjorn Kurten notes that Pleistocene black bears grew as large as modern day grizzlies. I believe Pleistocene black bears were larger and fiercer than their modern day descendents because they had to survive confrontations with saber-tooths, giant panthers, jaguars, and packs of dire wolves. Cavers and scientists discovered black bear fossils at Ladds and Kingston Saltpeter Cave in Bartow County, and the Isle of Hope Site in Chatham County. They’re also commonly found in Florida fossil sites but only a few have been recorded from South Carolina.
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Post by brobear on Jun 20, 2020 7:20:49 GMT -5
shaggygod.proboards.com/thread/643/american-black-bear-profile FOSSIL RECORD Ursine bears originated in the mid-Pleistocene (Kurte´n and Anderson 1980). All species of Ursidae diverged from a common ancestor 4–8 3 106 years ago (Goldman et al. 1989). Fossil records of U. americanus range from early Irvingtonian to Recent (Kurte´n and Anderson 1980; Savage and Russell 1983). U.americanus was the most common ursid in the late Rancholabrean of North America (Kurte´n and Anderson 1980). The closest living relative of U. americanus is either the Old World species U. thibetanus (Talbot and Shields 1996) or the sun bear (Helarctos malayanus—Zhang and Ryder 1994). U. americanus probably arose from a Holarctic population represented in North America by U. abstrusus (Savage and Russell 1983). Early forms were small but gradually increased in size through the late Irvingtonian and Rancholabrean (Kurte´n and Anderson 1980; Nagorsen et al. 1995). Late Pleistocene American black bears generally were larger than modern American black bears from the same area (Graham 1991).
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Post by brobear on Jul 14, 2020 13:41:39 GMT -5
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Post by OldGreenGrolar on Oct 19, 2020 21:50:36 GMT -5
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Post by brobear on Apr 26, 2021 3:26:21 GMT -5
www.sciencedaily.com/releases/2021/04/210419135714.htm Stone Age black bears didn't just defecate in the woods - they did it in a cave too. Scientists have sequenced ancient DNA from soil for the first time and the advance will transform what is known about everything from evolution to climate change. The findings have been described as the 'moon landings' of genomics because researchers will no longer have to rely on finding and testing fossils to determine genetic ancestry, links and discoveries - and it is thanks to Stone Age black bears who defecated in a remote cave in Mexico 16,000 years ago.
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!