Post by DinosaurMichael on Feb 28, 2012 19:29:09 GMT -5
Bull Hippopotamus - Hippopotamus amphibius
The hippopotamus (Hippopotamus amphibius), or hippo, from the ancient Greek for "river horse" (ἱπποπόταμος), is a large, mostly herbivorous mammal in sub-Saharan Africa, and one of only two extant species in the family Hippopotamidae (the other is the Pygmy Hippopotamus.) After the elephant and rhinoceros, the hippopotamus is the third largest land mammal and the heaviest extant artiodactyl. The hippopotamus is semi-aquatic, inhabiting rivers, lakes and mangrove swamps where territorial bulls preside over a stretch of river and groups of 5 to 30 females and young. During the day they remain cool by staying in the water or mud; reproduction and childbirth both occur in water. They emerge at dusk to graze on grass. While hippopotamuses rest near each other in the water, grazing is a solitary activity and hippos are not territorial on land. Despite their physical resemblance to pigs and other terrestrial even-toed ungulates, their closest living relatives are cetaceans (whales, porpoises, etc.) from which they diverged about 55 million years ago. The common ancestor of whales and hippos split from other even-toed ungulates around 60 million years ago. The earliest known hippopotamus fossils, belonging to the genus Kenyapotamus in Africa, date to around 16 million years ago. The hippopotamus is recognizable by its barrel-shaped torso, enormous mouth and teeth, nearly hairless body, stubby legs and tremendous size. It is the third largest land mammal by weight (between 1½ and 3 tonnes), behind the white rhinoceros (1½ to 3½ tonnes) and the three species of elephant (3 to 9 tonnes). The hippopotamus is one of the largest quadrupeds (four legged mammals). Despite its stocky shape and short legs, it can easily outrun a human. Hippos have been clocked at 30 km/h (19 mph) over short distances. The hippopotamus is one of the most aggressive creatures in the world and is often regarded as one of the most dangerous animals in Africa. There are an estimated 125,000 to 150,000 hippos throughout Sub-Saharan Africa; Zambia (40,000) and Tanzania (20,000–30,000) possess the largest populations. They are still threatened by habitat loss and poaching for their meat and ivory canine teeth. Hippopotamuses are among the largest living mammals; only elephants and some rhinoceroses and whales are heavier. They can live in the water or on land. Their specific gravity allows them to sink and walk or run along the bottom of a river. Hippos are considered megafauna, but unlike all other African megafauna, hippos have adapted for a semi-aquatic life in freshwater lakes and rivers. Because of their enormous size, hippopotamuses are difficult to weigh in the wild. Most estimates of the weight come from culling operations that were carried out in the 1960s. The average weights for adult males ranged between 1,500–1,800 kg (3,300–4,000 lb). Females are smaller than their male counterparts, with average weights measuring between 1,300–1,500 kg (2,900–3,300 lb). Older males can get much larger, reaching at least 3,200 kg (7,100 lb) and occasionally weighing 4,500 kg (9,900 lb). Male hippos appear to continue growing throughout their lives; females reach a maximum weight at around age 25.
Southern Elephant Seal - Mirounga leonina
The Southern Elephant Seal (Mirounga leonina) is one of the two extant species of elephant seal. It is both the largest pinniped and member of the order Carnivora living today. The seal gets its name from its great size and the large proboscis of the adult males, which is used to make extraordinarily loud roaring noises, especially during the mating season. The Southern Elephant Seal is distinguished from the Northern Elephant Seal (which doesn't overlap in range with this species) by its greater body mass and a wider proboscis. This seals' size shows extreme sexual dimorphism, possibly the largest of any mammal, with the males typically five to six times heavier than the females. While the females average 400 to 900 kilograms (880 to 2,000 lb) and 2.6 to 3 meters (8.5 to 9.8 ft) long, the bulls average 2,200 to 4,000 kilograms (4,900 to 8,800 lb) and 4.5 to 5.8 meters (15 to 19 ft) long. The record-sized bull, shot in Possession Bay, South Georgia on February 28, 1913, measured 6.85 meters (22.5 ft) long and was estimated to weigh 5,000 kilograms (11,000 lb). The maximum size of a female is 1,000 kilograms (2,200 lb) and 3.7 meters (12 ft). The eyes are large, round and black. The width of the eyes, and a high concentration of low light pigments, suggest that sight plays an important role in the capture of prey. Like all seals, elephant seals have hind limbs whose ends form the tail and tail fin. Each of the "feet" can deploy five long webbed fingers. This agile dual palm is used to propel water. The pectoral fins are used little while swimming. While the hind limbs are unfit for locomotion on land, elephant seals use their fins as support to propel their bodies. They are able to propel themselves quickly (as fast as 8 kilometres per hour or 5.0 miles per hour) in this way for short-distance travel, to return to water, to catch up with a female, or to chase an intruder. Pups are born with fur and are completely black. Their coat is unsuited to water, but protects infants by insulating them from the cold air. The first moulting accompanies weaning. After moulting, the coats may turn grey and brown, depending on the thickness and moisture of hair. Among older males, the skin takes the form of a thick leather which is often scarred. Like other seals, the vascular system of elephant seals is adapted to the cold; a mixture of small veins surround arteries, capturing heat from them. This structure is present in extremities such as the hind legs.
The hippopotamus (Hippopotamus amphibius), or hippo, from the ancient Greek for "river horse" (ἱπποπόταμος), is a large, mostly herbivorous mammal in sub-Saharan Africa, and one of only two extant species in the family Hippopotamidae (the other is the Pygmy Hippopotamus.) After the elephant and rhinoceros, the hippopotamus is the third largest land mammal and the heaviest extant artiodactyl. The hippopotamus is semi-aquatic, inhabiting rivers, lakes and mangrove swamps where territorial bulls preside over a stretch of river and groups of 5 to 30 females and young. During the day they remain cool by staying in the water or mud; reproduction and childbirth both occur in water. They emerge at dusk to graze on grass. While hippopotamuses rest near each other in the water, grazing is a solitary activity and hippos are not territorial on land. Despite their physical resemblance to pigs and other terrestrial even-toed ungulates, their closest living relatives are cetaceans (whales, porpoises, etc.) from which they diverged about 55 million years ago. The common ancestor of whales and hippos split from other even-toed ungulates around 60 million years ago. The earliest known hippopotamus fossils, belonging to the genus Kenyapotamus in Africa, date to around 16 million years ago. The hippopotamus is recognizable by its barrel-shaped torso, enormous mouth and teeth, nearly hairless body, stubby legs and tremendous size. It is the third largest land mammal by weight (between 1½ and 3 tonnes), behind the white rhinoceros (1½ to 3½ tonnes) and the three species of elephant (3 to 9 tonnes). The hippopotamus is one of the largest quadrupeds (four legged mammals). Despite its stocky shape and short legs, it can easily outrun a human. Hippos have been clocked at 30 km/h (19 mph) over short distances. The hippopotamus is one of the most aggressive creatures in the world and is often regarded as one of the most dangerous animals in Africa. There are an estimated 125,000 to 150,000 hippos throughout Sub-Saharan Africa; Zambia (40,000) and Tanzania (20,000–30,000) possess the largest populations. They are still threatened by habitat loss and poaching for their meat and ivory canine teeth. Hippopotamuses are among the largest living mammals; only elephants and some rhinoceroses and whales are heavier. They can live in the water or on land. Their specific gravity allows them to sink and walk or run along the bottom of a river. Hippos are considered megafauna, but unlike all other African megafauna, hippos have adapted for a semi-aquatic life in freshwater lakes and rivers. Because of their enormous size, hippopotamuses are difficult to weigh in the wild. Most estimates of the weight come from culling operations that were carried out in the 1960s. The average weights for adult males ranged between 1,500–1,800 kg (3,300–4,000 lb). Females are smaller than their male counterparts, with average weights measuring between 1,300–1,500 kg (2,900–3,300 lb). Older males can get much larger, reaching at least 3,200 kg (7,100 lb) and occasionally weighing 4,500 kg (9,900 lb). Male hippos appear to continue growing throughout their lives; females reach a maximum weight at around age 25.
Southern Elephant Seal - Mirounga leonina
The Southern Elephant Seal (Mirounga leonina) is one of the two extant species of elephant seal. It is both the largest pinniped and member of the order Carnivora living today. The seal gets its name from its great size and the large proboscis of the adult males, which is used to make extraordinarily loud roaring noises, especially during the mating season. The Southern Elephant Seal is distinguished from the Northern Elephant Seal (which doesn't overlap in range with this species) by its greater body mass and a wider proboscis. This seals' size shows extreme sexual dimorphism, possibly the largest of any mammal, with the males typically five to six times heavier than the females. While the females average 400 to 900 kilograms (880 to 2,000 lb) and 2.6 to 3 meters (8.5 to 9.8 ft) long, the bulls average 2,200 to 4,000 kilograms (4,900 to 8,800 lb) and 4.5 to 5.8 meters (15 to 19 ft) long. The record-sized bull, shot in Possession Bay, South Georgia on February 28, 1913, measured 6.85 meters (22.5 ft) long and was estimated to weigh 5,000 kilograms (11,000 lb). The maximum size of a female is 1,000 kilograms (2,200 lb) and 3.7 meters (12 ft). The eyes are large, round and black. The width of the eyes, and a high concentration of low light pigments, suggest that sight plays an important role in the capture of prey. Like all seals, elephant seals have hind limbs whose ends form the tail and tail fin. Each of the "feet" can deploy five long webbed fingers. This agile dual palm is used to propel water. The pectoral fins are used little while swimming. While the hind limbs are unfit for locomotion on land, elephant seals use their fins as support to propel their bodies. They are able to propel themselves quickly (as fast as 8 kilometres per hour or 5.0 miles per hour) in this way for short-distance travel, to return to water, to catch up with a female, or to chase an intruder. Pups are born with fur and are completely black. Their coat is unsuited to water, but protects infants by insulating them from the cold air. The first moulting accompanies weaning. After moulting, the coats may turn grey and brown, depending on the thickness and moisture of hair. Among older males, the skin takes the form of a thick leather which is often scarred. Like other seals, the vascular system of elephant seals is adapted to the cold; a mixture of small veins surround arteries, capturing heat from them. This structure is present in extremities such as the hind legs.
