Post by DinosaurMichael on Jul 23, 2012 11:30:49 GMT -5
2 Gray Wolves - Canis lupus
The gray wolf (Canis lupus) is a member of the Canidae family and also known as the Arctic wolf, common wolf, Mexican wolf, Plains wolf, timber wolf, Tundra wolf. The species was the world's most widely distributed mammal but has become extinct in much of Western Europe, in Mexico and much of the USA. Wolves occur primarily but not exclusively in wilderness and remote areas. Their original worldwide range has been reduced by about one-third by deliberate persecution due to depredation on livestock and fear of attacks on humans. Although the species still faces some threats, it is relatively widespread with a stable population trend and has therefore been assessed as Least Concern by IUCN since 2004. Canis lupus excludes the domestic dog and the dingo. Though once abundant over much of Eurasia, North Africa and North America, the gray wolf inhabits a reduced portion of its former range due to widespread destruction of its territory, human encroachment, and the resulting human-wolf encounters that sparked broad extirpation. Today, wolves are protected in some areas, hunted for sport in others, or may be subject to population control or extermination as threats to livestock, people, and pets. Gray wolves are social predators that live in nuclear families consisting of a mated pair, their offspring and, occasionally, adopted immature wolves. They primarily feed on ungulates, which they hunt by wearing them down in short chases. Gray wolves are typically apex predators throughout their range, with only humans and tigers posing significant threats to them. Genetic studies reaffirm that the gray wolf is the ancestor of the domestic dog. A number of other Canis lupus subspecies have been identified, though the actual number of subspecies is still open to discussion. In areas where human cultures and wolves both occur, wolves frequently feature in the folklore and mythology of those cultures, both positively and negatively. Gray wolves are the largest extant members of the Canidae, excepting certain large breeds of domestic dog. Gray wolf weight and size can vary greatly worldwide, tending to increase proportionally with latitude as predicted by Bergmann's Rule. Adult wolves are 105–160 cm (41–63 in) in length and 80–85 cm (32–34 in) in shoulder height. The tail is ⅔ the length of the head and body, measuring 29–50 cm (11–20 in) in length. The ears are 90–110 millimeters (3.5–4.3 in) in height, and the hind feet are 220–250 mm. Wolf weight varies geographically; on average, European wolves may weigh 38.5 kilograms (85 lb), North American wolves 36 kilograms (79 lb), Indian and Arabian wolves 25 kilograms (55 lb) and North African wolves 13 kilograms (29 lb). Females in any given wolf population typically weigh 5–10 lbs less than males. Wolves weighing over 54 kg (120 lbs) are uncommon, though exceptionally large individuals have been recorded in Alaska, Canada, and the former Soviet Union. The heaviest recorded gray wolf in North America was killed on 70 Mile River in east-central Alaska on July 12, 1939 and weighed 79.4 kilograms (175 lb), while the heaviest recorded wolf in Eurasia was killed after World War II in the Kobelyakski Area of the Poltavskij Region, Ukrainian SSR, and weighed 86 kilograms (190 lb).
Dire Wolf - Canis dirus
The dire wolf (Canis dirus) is an extinct carnivorous mammal of the genus Canis related to the smaller extant gray wolf. It was most common in North America and South America from the Irvingtonian stage to the Rancholabrean stage of the Pleistocene epoch, living 1.80 Ma—10,000 years ago, persisting for approximately 1.79 million years. The fossil record suggests that the genus Canis diverged from the small, foxlike Leptocyon in North America sometime in the Late Miocene epoch 9 to 10 million years (Ma) ago, along with two other genera, Urocyon, and Vulpes. Canids soon spread to Asia and Europe (8 Ma BP) and became the ancestors of modern wolves, jackals, foxes, and the Raccoon Dog. By 3–5 Ma BP, canids had spread to Africa (Early Pliocene) and South America (Late Pliocene). Their invasion of South America as part of the Great American Interchange was enabled by the formation of the Isthmus of Panama 3 Ma ago. Although it was closely related to the gray wolf and other sister species, Canis dirus is not the direct ancestor of any species known today. Unlike the gray wolf, which is of Eurasian origin, the dire wolf evolved on the North American continent, along with the coyote. The Dire Wolf co-existed with the Gray Wolf in North America for about 100,000 years. The dire wolf was one of the abundant Pleistocene megafauna—a wide variety of very large mammals that lived during the Pleistocene. Approximately 10,000 years ago the dire wolf became extinct along with most other North American megafauna.[9] During the Late Pleistocene (300,000 years ago) the gray wolf (Canis lupus) crossed into North America on the Bering Strait land bridge and competed with the dire wolf. Starting about 16,000 years ago, coinciding with the end of the last glacial period and the arrival of humans in North America, most of the large mammals upon which the dire wolf depended for prey began to die out (possibly as a result of climate and/or human-induced changes as suggested in a 2008 National Geographic Channel documentary). Slower than the other wolf species on the continent at the time, primarily the gray wolf and red wolf, it could not hunt the swifter species that remained and was forced to subsist by scavenging. By 10,000 years ago, the large mammals and the Dire Wolf were extinct. The dire wolf was larger than the gray wolf, averaging about 1.5 metres (5 ft) in length and weighing between 50 kg (110 lb) and 79 kg (174 lb). Despite superficial similarities to the Gray Wolf, there were significant differences between the two species. The legs of the dire wolf were proportionally shorter and sturdier than those of the gray wolf, and its brain case was smaller than that of a similarly sized gray wolf. The dire wolf's teeth were similar to the gray wolf's, only slightly larger, pointing to a hypercarnivorous to mesocarnivorous activity.
The gray wolf (Canis lupus) is a member of the Canidae family and also known as the Arctic wolf, common wolf, Mexican wolf, Plains wolf, timber wolf, Tundra wolf. The species was the world's most widely distributed mammal but has become extinct in much of Western Europe, in Mexico and much of the USA. Wolves occur primarily but not exclusively in wilderness and remote areas. Their original worldwide range has been reduced by about one-third by deliberate persecution due to depredation on livestock and fear of attacks on humans. Although the species still faces some threats, it is relatively widespread with a stable population trend and has therefore been assessed as Least Concern by IUCN since 2004. Canis lupus excludes the domestic dog and the dingo. Though once abundant over much of Eurasia, North Africa and North America, the gray wolf inhabits a reduced portion of its former range due to widespread destruction of its territory, human encroachment, and the resulting human-wolf encounters that sparked broad extirpation. Today, wolves are protected in some areas, hunted for sport in others, or may be subject to population control or extermination as threats to livestock, people, and pets. Gray wolves are social predators that live in nuclear families consisting of a mated pair, their offspring and, occasionally, adopted immature wolves. They primarily feed on ungulates, which they hunt by wearing them down in short chases. Gray wolves are typically apex predators throughout their range, with only humans and tigers posing significant threats to them. Genetic studies reaffirm that the gray wolf is the ancestor of the domestic dog. A number of other Canis lupus subspecies have been identified, though the actual number of subspecies is still open to discussion. In areas where human cultures and wolves both occur, wolves frequently feature in the folklore and mythology of those cultures, both positively and negatively. Gray wolves are the largest extant members of the Canidae, excepting certain large breeds of domestic dog. Gray wolf weight and size can vary greatly worldwide, tending to increase proportionally with latitude as predicted by Bergmann's Rule. Adult wolves are 105–160 cm (41–63 in) in length and 80–85 cm (32–34 in) in shoulder height. The tail is ⅔ the length of the head and body, measuring 29–50 cm (11–20 in) in length. The ears are 90–110 millimeters (3.5–4.3 in) in height, and the hind feet are 220–250 mm. Wolf weight varies geographically; on average, European wolves may weigh 38.5 kilograms (85 lb), North American wolves 36 kilograms (79 lb), Indian and Arabian wolves 25 kilograms (55 lb) and North African wolves 13 kilograms (29 lb). Females in any given wolf population typically weigh 5–10 lbs less than males. Wolves weighing over 54 kg (120 lbs) are uncommon, though exceptionally large individuals have been recorded in Alaska, Canada, and the former Soviet Union. The heaviest recorded gray wolf in North America was killed on 70 Mile River in east-central Alaska on July 12, 1939 and weighed 79.4 kilograms (175 lb), while the heaviest recorded wolf in Eurasia was killed after World War II in the Kobelyakski Area of the Poltavskij Region, Ukrainian SSR, and weighed 86 kilograms (190 lb).
Dire Wolf - Canis dirus
The dire wolf (Canis dirus) is an extinct carnivorous mammal of the genus Canis related to the smaller extant gray wolf. It was most common in North America and South America from the Irvingtonian stage to the Rancholabrean stage of the Pleistocene epoch, living 1.80 Ma—10,000 years ago, persisting for approximately 1.79 million years. The fossil record suggests that the genus Canis diverged from the small, foxlike Leptocyon in North America sometime in the Late Miocene epoch 9 to 10 million years (Ma) ago, along with two other genera, Urocyon, and Vulpes. Canids soon spread to Asia and Europe (8 Ma BP) and became the ancestors of modern wolves, jackals, foxes, and the Raccoon Dog. By 3–5 Ma BP, canids had spread to Africa (Early Pliocene) and South America (Late Pliocene). Their invasion of South America as part of the Great American Interchange was enabled by the formation of the Isthmus of Panama 3 Ma ago. Although it was closely related to the gray wolf and other sister species, Canis dirus is not the direct ancestor of any species known today. Unlike the gray wolf, which is of Eurasian origin, the dire wolf evolved on the North American continent, along with the coyote. The Dire Wolf co-existed with the Gray Wolf in North America for about 100,000 years. The dire wolf was one of the abundant Pleistocene megafauna—a wide variety of very large mammals that lived during the Pleistocene. Approximately 10,000 years ago the dire wolf became extinct along with most other North American megafauna.[9] During the Late Pleistocene (300,000 years ago) the gray wolf (Canis lupus) crossed into North America on the Bering Strait land bridge and competed with the dire wolf. Starting about 16,000 years ago, coinciding with the end of the last glacial period and the arrival of humans in North America, most of the large mammals upon which the dire wolf depended for prey began to die out (possibly as a result of climate and/or human-induced changes as suggested in a 2008 National Geographic Channel documentary). Slower than the other wolf species on the continent at the time, primarily the gray wolf and red wolf, it could not hunt the swifter species that remained and was forced to subsist by scavenging. By 10,000 years ago, the large mammals and the Dire Wolf were extinct. The dire wolf was larger than the gray wolf, averaging about 1.5 metres (5 ft) in length and weighing between 50 kg (110 lb) and 79 kg (174 lb). Despite superficial similarities to the Gray Wolf, there were significant differences between the two species. The legs of the dire wolf were proportionally shorter and sturdier than those of the gray wolf, and its brain case was smaller than that of a similarly sized gray wolf. The dire wolf's teeth were similar to the gray wolf's, only slightly larger, pointing to a hypercarnivorous to mesocarnivorous activity.
