Post by DinosaurMichael on May 21, 2012 6:39:25 GMT -5
Kodiak Bear - Ursus arctos middendorffi
The Kodiak bear (Ursus arctos middendorffi), also known as the Kodiak brown bear or the Alaskan grizzly bear or American brown bear, occupies the islands of the Kodiak Archipelago in South-Western Alaska. Its name in the Alutiiq language is Taquka-aq. It is the largest subspecies of brown bear. Few Kodiak bears have been weighed in the wild, so some of the weights are estimates. Size range for females is from 225 kg (500 lbs) to 315 kg (700 lbs) and for males 360 kg (800 lbs) to 635 kg (1400 lbs). Mature males average 480–533 kg (1,058–1,175 lb) over the course of the year, and can weigh up to 680 kg (1500 lbs) at peak times. Females are typically about 20% smaller and 30% lighter than males and adult sizes are attained when bears are 6 years old. Bears weigh the least when they emerge from their dens in the spring, and can increase their weight by 20–30% during late summer and fall. Bears in captivity can sometimes attain weights considerably greater than those of wild bears. An adult male Kodiak bear stands up to 1.5 m (5 ft) tall at the shoulder when it is standing on all four legs. When standing fully upright on its hind legs, a large male could reach a height of 3 m (10 ft). The largest Kodiak bear on record grew in captivity and died in the Cheyenne Mountain Zoo in December 1955, weighing 757 kg (1670 lb). They are the largest brown bear subspecies, and are comparable in size to polar bears. That makes Kodiak bears and polar bears both the two largest members of the bear family and the two largest extant wholly terrestrial carnivores. The standard method of evaluating the size of bears is by measuring their skulls. Most North American hunting organizations and management agencies use calipers to measure the length of the skull (back of sagittal crest on the back of the skull to the front tooth) and the width (maximum width between the zygomatic arches — “cheek bones”). The total skull size is the sum of these two measurements. The largest bear ever killed in North America was from Kodiak Island with a total skull size of 78.1 cm (30.75 in), and 8 of the top 10 brown bears listed in the Boone and Crockett record book are from Kodiak. The average skull size of Kodiak bears that were killed by hunters in the first five years of the 21st century was 63.8 cm (25.1 in) for boars and 55.4 cm (21.8 in) for sows. Although the term “Kodiak bear” is widely used to include all coastal Alaska brown bears, the subspecies only occurs on the islands of the Kodiak Archipelago (Kodiak, Afognak, Shuyak, Raspberry, Uganik, Sitkalidak, and adjacent islands). The Kodiak bear population was estimated to include 3,526 bears in 2005, yielding an estimated archipelago-wide population density of 0.7 bears/square mile (271.2 bears/1000 km²). During the past decade the population has been slowly increasing.
Cave Bear - Ursus spelaeus
The cave bear (Ursus spelaeus) was a species of bear that lived in Europe during the Pleistocene and became extinct at the beginning of the Last Glacial Maximum about 27,500 years ago. Both the name cave and the scientific name spelaeus derive from the fact that fossils of this species were mostly found in caves, indicating that this species spent more time in caves than the brown bear, which only uses caves for hibernation. Consequently, in the course of time, whole layers of bones, almost entire skeletons, were found in many caves. Cave bear skeletons were first described in 1774 by Johann Friederich Esper in his book Newly Discovered Zoolites of Unknown Four Footed Animals. Originally thought to belong to dragons, unicorns, apes, canids or felids, Esper postulated that they actually belonged to polar bears. Twenty years later, Johann Christian Rosenmüller, an anatomist at the Leipzig University, gave the species its binomial name. The bones were so numerous that most researchers held little respect for them. During World War I, large amounts of cave bear bones were used as a source of phosphates, leaving behind little more than skulls and leg bones. Many caves in Central Europe have skeletons of cave bears inside, for example the Heinrichshöhle in Hemer or the Dechenhöhle in Iserlohn, Germany. In Romania, there is a cave called Bears' Cave where 140 cave bear skeletons were discovered in 1983. The cave bear's range stretched across Europe, from Spain to Eurasia, from Italy and Greece to Belgium, the Netherlands and Great Britain, across a portion of Germany through Poland, then south into Hungary, Romania and parts of Russia, Caucasus and northern Iran. 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. The cave bear inhabited low mountainous areas, especially in regions rich in limestone caves. They seem to have avoided open plains, preferring forested or forest-edged terrains. The cave bear had a very broad, domed skull with a steep forehead. Its stout body had long thighs, massive shins and in-turning feet, making it similar in skeletal structure to the brown bear. Cave bears were comparable in size to the largest modern day bears. The average weight for males was 400–500 kilograms (880–1102 pounds), while females weighed 225–250 kg (496–551 lbs). Of cave bear skeletons in museums, 90% 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. Cave bears of the last ice age lacked the usual 2–3 premolars present in other bears; to compensate, the last molar is very elongated, with supplementary cusps. The humerus of the cave bear was similar in size to that of the polar bear, as were the femora of females. The femora of male cave bears, however, bore more similarities in size to those of kodiak bears.
The Kodiak bear (Ursus arctos middendorffi), also known as the Kodiak brown bear or the Alaskan grizzly bear or American brown bear, occupies the islands of the Kodiak Archipelago in South-Western Alaska. Its name in the Alutiiq language is Taquka-aq. It is the largest subspecies of brown bear. Few Kodiak bears have been weighed in the wild, so some of the weights are estimates. Size range for females is from 225 kg (500 lbs) to 315 kg (700 lbs) and for males 360 kg (800 lbs) to 635 kg (1400 lbs). Mature males average 480–533 kg (1,058–1,175 lb) over the course of the year, and can weigh up to 680 kg (1500 lbs) at peak times. Females are typically about 20% smaller and 30% lighter than males and adult sizes are attained when bears are 6 years old. Bears weigh the least when they emerge from their dens in the spring, and can increase their weight by 20–30% during late summer and fall. Bears in captivity can sometimes attain weights considerably greater than those of wild bears. An adult male Kodiak bear stands up to 1.5 m (5 ft) tall at the shoulder when it is standing on all four legs. When standing fully upright on its hind legs, a large male could reach a height of 3 m (10 ft). The largest Kodiak bear on record grew in captivity and died in the Cheyenne Mountain Zoo in December 1955, weighing 757 kg (1670 lb). They are the largest brown bear subspecies, and are comparable in size to polar bears. That makes Kodiak bears and polar bears both the two largest members of the bear family and the two largest extant wholly terrestrial carnivores. The standard method of evaluating the size of bears is by measuring their skulls. Most North American hunting organizations and management agencies use calipers to measure the length of the skull (back of sagittal crest on the back of the skull to the front tooth) and the width (maximum width between the zygomatic arches — “cheek bones”). The total skull size is the sum of these two measurements. The largest bear ever killed in North America was from Kodiak Island with a total skull size of 78.1 cm (30.75 in), and 8 of the top 10 brown bears listed in the Boone and Crockett record book are from Kodiak. The average skull size of Kodiak bears that were killed by hunters in the first five years of the 21st century was 63.8 cm (25.1 in) for boars and 55.4 cm (21.8 in) for sows. Although the term “Kodiak bear” is widely used to include all coastal Alaska brown bears, the subspecies only occurs on the islands of the Kodiak Archipelago (Kodiak, Afognak, Shuyak, Raspberry, Uganik, Sitkalidak, and adjacent islands). The Kodiak bear population was estimated to include 3,526 bears in 2005, yielding an estimated archipelago-wide population density of 0.7 bears/square mile (271.2 bears/1000 km²). During the past decade the population has been slowly increasing.
Cave Bear - Ursus spelaeus
The cave bear (Ursus spelaeus) was a species of bear that lived in Europe during the Pleistocene and became extinct at the beginning of the Last Glacial Maximum about 27,500 years ago. Both the name cave and the scientific name spelaeus derive from the fact that fossils of this species were mostly found in caves, indicating that this species spent more time in caves than the brown bear, which only uses caves for hibernation. Consequently, in the course of time, whole layers of bones, almost entire skeletons, were found in many caves. Cave bear skeletons were first described in 1774 by Johann Friederich Esper in his book Newly Discovered Zoolites of Unknown Four Footed Animals. Originally thought to belong to dragons, unicorns, apes, canids or felids, Esper postulated that they actually belonged to polar bears. Twenty years later, Johann Christian Rosenmüller, an anatomist at the Leipzig University, gave the species its binomial name. The bones were so numerous that most researchers held little respect for them. During World War I, large amounts of cave bear bones were used as a source of phosphates, leaving behind little more than skulls and leg bones. Many caves in Central Europe have skeletons of cave bears inside, for example the Heinrichshöhle in Hemer or the Dechenhöhle in Iserlohn, Germany. In Romania, there is a cave called Bears' Cave where 140 cave bear skeletons were discovered in 1983. The cave bear's range stretched across Europe, from Spain to Eurasia, from Italy and Greece to Belgium, the Netherlands and Great Britain, across a portion of Germany through Poland, then south into Hungary, Romania and parts of Russia, Caucasus and northern Iran. 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. The cave bear inhabited low mountainous areas, especially in regions rich in limestone caves. They seem to have avoided open plains, preferring forested or forest-edged terrains. The cave bear had a very broad, domed skull with a steep forehead. Its stout body had long thighs, massive shins and in-turning feet, making it similar in skeletal structure to the brown bear. Cave bears were comparable in size to the largest modern day bears. The average weight for males was 400–500 kilograms (880–1102 pounds), while females weighed 225–250 kg (496–551 lbs). Of cave bear skeletons in museums, 90% 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. Cave bears of the last ice age lacked the usual 2–3 premolars present in other bears; to compensate, the last molar is very elongated, with supplementary cusps. The humerus of the cave bear was similar in size to that of the polar bear, as were the femora of females. The femora of male cave bears, however, bore more similarities in size to those of kodiak bears.