Bears
Bears | ||||||||||||
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Brown bear ( Ursus arctos ) |
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Systematics | ||||||||||||
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Scientific name | ||||||||||||
Ursidae | ||||||||||||
Fischer , 1817 |
The bears (Ursidae) are a family of mammals from the order of the carnivores (Carnivora). In contrast to the small bears (Procyonidae), they are also referred to as big bears or real bears . The family includes eight species and belongs to the superfamily of the canine species .
features
The bears are similar in physique. Their bodies are massive and stocky, their heads large, and their limbs are rather short and very strong. The eyes are small, the ears round and erect. The mostly elongated snout houses 40 or 42 teeth, depending on the species. The feet end in five toes with non-retractable claws. All bears are sole walkers , whereby the soles of the feet are mostly hairy; only in species that often climb trees, such as the sun bears , are the soles of the feet bare. The tail is just a small stub. The fur is rather long and in most species monochrome, mostly brown or black. Exceptions are the giant panda with its striking black and white fur pattern and the white polar bear . In several species, there may be light markings on the chest or face.
The body weight varies between 25 and 800 kilograms, with the males always being significantly heavier than the females. The head-torso length is 100 to 280 centimeters.
distribution and habitat
Bears are now native to Eurasia and America , although they only inhabit the northwestern part of South America . In Western and Central Europe there are only relic occurrences today. There are no bears left in Africa today; the atlas bear , a subspecies of the brown bear in the North African Atlas Mountains , died out in the 19th century . Bears are generalists about their habitat and inhabit a wide variety of habitats , from polar regions to grasslands to tropical rainforests . Only very dry areas are avoided.
Way of life
Bears are loners and generally lead a more crepuscular or nocturnal way of life (with the exception of the polar bear). To sleep, they often retreat to caves, hollow tree trunks or pits in the ground. Their usual movement is a rather slow and leisurely pass , but if necessary they can run up to 50 km / h. As a rule, bears climb well (especially the sun bear ) and can swim well.
Several species hibernate during the cold months . It is not a real hibernation, as the breathing rate and heartbeat drop significantly, but the body temperature only drops slightly and you are relatively easy to wake up. In late summer and autumn, they eat a supply of fat in order to retreat to a burrow or cave in the cold season.
food
Bears are mostly omnivores , and depending on the species and season, they eat plant and animal foods to a different extent. Fruits and other parts of plants make up a large part of the diet of many species, supplemented by insects and their larvae and small vertebrates such as fish or rodents . To varying degrees, they also prey on larger vertebrates up to deer size, and sometimes also cattle. Deviations from this pattern are the giant panda , which feeds almost exclusively on bamboo , and the polar bear , which is the only predominant carnivore within this group.
Reproduction
The female gives birth to offspring every one to four years. Most births occur between November and February, when the female hibernates. Mating occurs many months in advance. From most types delayed implantation is known: The fertilized egg is often several months in the uterus kept before it the preimplantation period comes.
The actual gestation period is very short at 60 to 70 days; the one to four (usually two) newborns are extremely small. Within the placenta animals, bears are among the animals with the greatest difference in weight between a female and her litter. Only the mother takes care of the offspring. During this time, it is decidedly aggressive and attacks almost every intruder - including males and humans. It is discontinued after three to nine months. The young animals stay with their mother at least until the first autumn, but usually for 18 to 24 months. Sexual maturity occurs at three to six years of age, but males often do not grow in size until they are 10 to 11 years old.
Bears are long-lived animals; in the wild they can live to be 20 to 30 years old, in human care up to 50 years.
People and bears
Probably because of their size and strength, bears play an important role in the mythology and cult of many peoples. Bear cults were and are widespread among numerous wild-hunter peoples . Bear-shaped gods were also known to the Celts , among others , and numerous myths indicate that these animals were worshiped. In heraldry , too, numerous images of bears can be found (e.g. coat of arms of Berlin , coat of arms of Bern ), they also appear in numerous fairy tales and legends of many peoples.
At the same time as the veneration, however, the hunted for these animals took place for various reasons. Different parts of the body are used: the meat is eaten, the bearskin is made into clothing or blankets, and teeth and claws are used for ornamental purposes. Often, parts of the body of bears are said to have a medicinal effect, in particular the bile of the collar bears is used in Chinese medicine ( bear bile ).
Bears were and are also captured for entertainment purposes. In show fights, called Bärenhatzen , the animals were allowed in ancient times to dogs or humans struggling as dancing bears they provided entertainment, and today they will gladly kept in zoos or bears trenches, partly in poor conditions. In some cases since the late 1990s, there have been several bear protection facilities around the world , in which bears that have been exploited by humans as described are supposed to lead a species-appropriate life.
Another reason for hunting is to view bears as competitors for food and a potential threat to humans. Bears often kill grazing animals and plunder beehives or fish ponds. However, the actual extent of this damage is often exaggerated. Bears usually avoid people. But if they see their young, their food supplies threatened, or they are wounded, people can be attacked - often with fatal results. Unprovoked attacks are rare, but several people die each year from swipes or bites from bears.
For all these reasons, including the destruction of the habitat by human settlement activity, many species have become rare or have completely disappeared in certain regions. Brown bears, for example, are only found in relic populations in the core area of the USA and in Western and Central Europe ; in North Africa and Mexico they are completely extinct. The sun bear and especially the giant panda are also endangered species.
Naming and etymology
The actual word for “bear” in Urindo-European must have had the root * h 2 r̥tḱ- , as can be deduced from words like Greek arktós , Latin ursus (<* urcsus <* urctus ), ancient Indian ŕ̥kṣa and Hittite ḫartaka- . Also, in some Celtic languages the root is obtained, in Old Irish (art), in Welsh (arth) and Breton (arz). The root also appears in the names of the Celtic deities Artaios and Artio and among the Greeks in the names of the mythological figures Artemis and Arkas . The root word bear occurs only in Germanic languages ( English bear, Dutch beer, Scandinavian björn ) and is derived from an old word for "brown". Another theory derives the word from an Indo-European root * g wh er for “wild animal” (related to the Latin ferus ), but this is aloud less plausible. Another theory, which is also not plausible in terms of sound, suggests that the word bear comes from the old Germanic who for “man” (compare werewolf ), which refers to the bear's ability to stand on two legs like a person. Due to the special position of the Germanic languages, it is assumed that the Germanic word originated as a kind of taboo word ("brown" instead of "bear"), with the help of which, for magical reasons, the use of the actual bear word should be avoided to denote the mighty predator not imploring to "summon". In this context, the paraphrasing Beowulf ("beewolf") could have come about. A similar background can be assumed in the Slavic languages , where the bear is regularly called “honey eater” ( Russian медведь , Ukrainian ведмідь , Polish niedźwiedź , Czech medvěd , Slovenian medved , Croatian medvjed ).
Systematics
External system
Bears are among the carnivores (Carnivora) and belong to the canine species (Canoidea). There is a close relationship to the small bears (Procyonidae). The seals may also have evolved from bear-like ancestors. The oldest known representative in the bear's line of development is the extinct genus Parictis , which was often added to the extinct Amphicynodontidae. The Amphicynodontidae are possibly also paraphyletic and could also be closer to seals than to bears. Closer relatives of the bears were the Hemicyonidae "half bears". Amphicynodontidae and Hemicyonidae are sometimes classified as subfamilies in the Ursidae or combined with them as superfamily Ursoidea.
Internal system
The bear family is divided into three recent subfamilies with a total of five genera, eight species and several subspecies:
list
Subfamily Ursinae Swainson , 1835 - 3 genera, 6 species | ||||||
Genus Ursus Linnaeus , 1758 - 4 species | ||||||
German name | Scientific name | distribution | Hazard level Red List of IUCN |
Remarks | image | |
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American black bear |
Ursus americanus Pallas , 1780 |
North America : Canada , USA : |
( Least Concern - not at risk) | 16 recent subspecies The species is widespread in large parts of North America, mainly in the western United States, northern Mexico and all of Canada and Alaska. Estimates go from 850,000 to 950,000 copies. |
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Collar bear |
Ursus thibetanus G. Cuvier , 1823 |
( Vulnerable - endangered) | 7 recent subspecies They are native to Southeast Asia, at the foot of the Himalayas, and in Taiwan and Japan. The species is considered endangered due to illegal hunting and habitat loss. There are no reliable estimates of stocks. |
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brown bear |
Ursus arctos Linnaeus , 1758 |
( Least Concern - not at risk) | 14 to 16 recent subspecies, of which 3 are extinct. The distribution includes large parts of the northwest of North America, Europe and the Asian part of Russia. Including the grizzly . With over 200,000 estimated specimens worldwide, the species is considered secured. |
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Icebear |
Ursus maritimus Phipps , 1774 |
( Vulnerable - endangered) |
monotypical The polar bear is predominantly at home on the migrating pack ice borders of the Arctic, in northern Canada, on Svalbard and Greenland. The population has decreased by around 30 percent in the last 45 years because the quality of the habitat and its area has decreased due to global warming . The species, whose population is estimated at 20,000 to 25,000 specimens, is endangered. |
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Genus Melursus Meyer , 1793 - 1 Art | ||||||
German name | Scientific name | distribution | Hazard level Red List of IUCN |
Remarks | image | |
Sloth bear |
Melursus ursinus ( Shaw , 1791) (or Ursus ursinus , see below) |
( Vulnerable - endangered) | 2 recent subspecies They live in Sri Lanka , India , Nepal and Bhutan . The population is estimated at around 20,000. The species is partially hunted in its habitat as it is considered a nuisance by the rural population. |
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Genus Helarctos Horsfield , 1825 - 1 species | ||||||
German name | Scientific name | distribution | Hazard level Red List of IUCN |
Remarks | image | |
Sun bear |
Helarctos malayanus ( Raffles , 1821) (or Ursus malayanus , see below) |
( Vulnerable - endangered) | 2 recent subspecies Native to the tropical rainforests of Southeast Asia. Its classification is partly controversial, it is sometimes assigned directly to the genus Ursus . The species is endangered. There are no current population estimates, but it is assumed that the large-scale deforestation of the forest has significantly reduced the population in recent years. |
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Subfamily short-snouted bears (Tremarctinae Merriam & Stock , 1925) - 1 genus, 1 species | ||||||
Genus Tremarctos Gervais , 1855 - 1 Art | ||||||
German name | Scientific name | distribution | Hazard level Red List of IUCN |
Remarks | image | |
Spectacled bear |
Tremarctos ornatus ( F. Cuvier , 1825) |
( Vulnerable - endangered) | monotypical It is native to the tropical Andes , making it the only native bear species in South America. The species is threatened because the habitat is decreasing by two to four percent per year. |
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Subfamily Ailuropodinae Grevé , 1894 - 1 genus, 1 species | ||||||
Genus Ailuropoda Milne-Edwards , 1870 - 1 species | ||||||
German name | Scientific name | distribution | Hazard level Red List of IUCN |
Remarks | image | |
Big panda |
Ailuropoda melanoleuca ( David , 1869) |
( Vulnerable - endangered) | monotypical The Ailuropodinae is also recently monotypical (the small panda is now assigned to its own family). The giant panda lives in remote areas in the interior of China . There are still a maximum of about 2500 copies. The species is endangered. |
Assignment
The giant panda is the only recent member of the subfamily Ailuropodinae. An extinct representative was among others Kretzoiarctos . Giant and lesser pandas used to be put together in their own family ( cat bears ), but this is now considered obsolete. Due to certain similarities in the DNA , small pandas are sometimes assigned to the bears as well or they are kept in their own family (Ailuridae); see systematics of the little panda .
The spectacled bear is the only recent representative of the short-snouted bears (Tremarctinae), a subfamily of its own, which also includes the extinct giant short-faced bears.
The other six species, i.e. brown bears, the two black bears, polar bears, sun bears and sloth bears, make up the subfamily Ursinae. In some classifications they are all assigned to the genus Ursus , in some Malay and sloth bears are listed in their own genus ( Helarctos or Melursus ). Then the genus Ursus would be paraphyletic according to the following cladogram. The extinct representatives of this group include Ursus minimus and the cave bear ( Ursus spelaeus ).
Simplified cladogram of bears according to Krause et al.
Bears (Ursidae) |
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A number of animal names end in "-bär" without these animals being related to the big or small bears. These are for example the anteater , the koala bear or the fur seal . Many butterflies from the family of Tiger moths (Arctiidae) are called "-Bär" or "-bärchen".
literature
- Bernd Brunner: A Brief History of the Bears . Claassen, Hamburg 2005, ISBN 3-546-00395-0
- Ronald M. Nowak: Walker's Mammals of the World . 6th edition. Johns Hopkins University Press, Baltimore 1999, ISBN 0-8018-5789-9 (English).
- Max Wellmann : Bear . In: Paulys Realencyclopadie der classischen Antiquity Science (RE). Volume II, 2, Stuttgart 1896, Col. 2759-2762.
- DE Wilson, DM Reeder: Mammal Species of the World . Johns Hopkins University Press, 2005, ISBN 0-8018-8221-4
Web links
- Rebecca Postanowicz: The Ursidae Family. Information on the individual species, with illustrations and distribution maps. (No longer available online.) 2008, archived from the original on May 21, 2008 ; accessed on March 28, 2013 .
Individual evidence
- ^ Friedrich Kluge: Etymological dictionary of the German language . Walter de Gruyter: Berlin 1957. p. 50, column II; P. 51, column I (article bear )
- ↑ a b c d e f g h Don E. Wilson & DeeAnn M. Reeder (eds.): Ursidae in Mammal Species of the World. A Taxonomic and Geographic Reference (3rd ed).
- ↑ Ursus americanus in the endangered Red List species the IUCN 2008. Posted by: Garshelis, DL, Crider, D. & van Manen, F. (IUCN SSC Bear Specialist Group), 2008. Retrieved on October 12 of 2008.
- ↑ Ursus thibetanus in the endangered Red List species the IUCN 2008. Posted by: Garshelis, DL & Steinmetz, R. (IUCN SSC Bear Specialist Group), 2008. Retrieved on October 12 of 2008.
- ↑ Ursus arctos in the endangered Red List species the IUCN 2008. Posted by: McLellan, BN, Servheen, C. & Huber, D. (IUCN SSC Bear Specialist Group), 2008. Retrieved on October 12 of 2008.
- ↑ Ursus maritimus in the endangered Red List species the IUCN 2008. Posted by: Schliebe, S., Wiig, Ø, Derocher, A. & Lunn, N. (IUCN SSC Polar Bear Specialist Group), 2008. Accessed on the 12th. October 2008.
- ↑ Melursus ursinus in the endangered Red List species the IUCN 2008. Posted by: Garshelis, DL, Ratnayeke S. & Chauhan, NPS (IUCN SSC Bear Specialist Group), 2008. Retrieved on October 14 of 2008.
- ↑ Helarctos malayanus in the endangered Red List species the IUCN 2012. Posted by: Fredriksson, G., Mason, R., Wong, S. & Garshelis, DL (IUCN SSC Bear Specialist Group), 2008. Accessed on March 24, 2013 .
- ↑ Tremarctos ornatus in the endangered Red List species the IUCN 2008. Posted by: Goldstein, I., Velez-Liendo, X., Paisley, S. & Garshelis, DL (IUCN SSC Bear Specialist Group), 2008. Accessed on 14th October 2008.
- ↑ Ailuropoda melanoleuca in the endangered Red List species the IUCN 2012. Posted by: Lu, Z, Wang, D. & Garshelis, DL (IUCN SSC Bear Specialist Group), 2008. Accessed March 24, 2013.
- ↑ Johannes Krause et al .: Mitochondrial genomes reveal an explosive radiation of extinct and extant bears near the Miocene-Pliocene boundary. BMC Evolutionary Biology 2008, doi: 10.1186 / 1471-2148-8-220