Post by DinosaurMichael on Jan 9, 2012 22:01:48 GMT -5
Ankylosaurus - Ankylosaurus magniventris
Ankylosaurus (which is pronounced /ˌæŋkɨlɵˈsɔrəs/ [ANG-ki-lo-SAWR-us] or /æŋˌkaɪlɵˈsɔrəs/ [ang-KIE-lo-SAWR-us], and which means "fused lizard") is a genus of ankylosaurid dinosaur, containing one species, A. magniventris. Fossils of Ankylosaurus are found in geologic formations dating to the very end of the Cretaceous Period (about 66.5–65.5 Ma ago) in western North America. Although a complete skeleton has not been discovered and several other dinosaurs are represented by more extensive fossil material, Ankylosaurus is often considered the archetypal armored dinosaur. Other ankylosaurids shared its well-known features—the heavily-armored body and massive bony tail club—but Ankylosaurus was the largest known member of the family. In comparison with modern land animals the adult Ankylosaurus was very large. Some scientists have estimated a length of 9 meters (30 ft). Another reconstruction suggests a significantly smaller size, at 6.25 m (20.5 ft) long, up to 1.5 m (5 ft) wide and about 1.7 m (5.5 ft) high at the hip. Ankylosaurus may have weighed over 6,000 kilograms (13,000 lb), making it one of the heaviest armored dinosaurs yet discovered. The body shape was low-slung and quite wide. It was quadrupedal, with the hind limbs longer than the forelimbs. Although its feet are still unknown, comparisons with other ankylosaurids suggest Ankylosaurus probably had five toes on each foot. The skull was low and triangular in shape, wider than it was long. The largest known skull measures 64.5 centimeters (25 in) long and 74.5 cm (29 in) wide. Like other ankylosaurs, Ankylosaurus was herbivorous, with small, leaf-shaped teeth suitable for cropping vegetation. These teeth were smaller, relative to the body size, than in any other ankylosaurid species. Ankylosaurus did not share the grinding tooth batteries of the contemporaneous ceratopsid and hadrosaurid dinosaurs, indicating that very little chewing occurred. Bones in the skull and other parts of the body were fused, increasing their strength.
Steppe Rhinoceros - Elasmotherium sibiricum
Elasmotherium ("Thin Plate Beast") is an extinct genus of giant rhinoceros endemic to Eurasia during the Late Pliocene through the Pleistocene, documented from 2.6 mya to as late as 50,000 years ago, possibly later, in the Late Pleistocene, an approximate span of slightly less than 2.6 million years. Three species are recognised. The best known, E. sibiricum was the size of a mammoth and is thought to have borne a large, thick horn on its forehead which was used for defense, attracting mates, driving away competitors, sweeping snow from the grass in winter and digging for water and plant roots. Like all rhinoceroses, elasmotheres were herbivorous. Unlike any others, its high-crowned molars were ever-growing. Its legs were longer than those of other rhinos and were designed for galloping, giving it a horse-like gait. The Russian paleontologists of the 19th century who discovered and named the initial fossils were influenced by ancient legends of a huge unicorn roaming the steppes of Siberia. To date no evidence either contradicts or confirms the possibility that Elasmotherium survived into legendary times. The most reconstructed species is perhaps E. sibiricum by generations of scientists working at the Paleontological Museum in Moscow and elsewhere in Russia. The majority of the fossils fall or have fallen within their national jurisdiction. The dimensions and morphology of the various reconstructions vary considerably. They are for the most part estimating the gross details from the minutiae. However, they all agree on the general order of magnitude, that sibiricum was comparable to a Mammoth and was rather larger than the contemporary Woolly Rhinoceros. E. sibiricum had a measured shoulder height of approximately 2 metres (6.6 ft). To it, however, must be added the height of a massive hump anchored on the fin-like transverse processes extending from the top of the cervical vertebrae, a maximum of 53 centimetres (1.74 ft). The total height then was in excess of 253 centimetres (8.30 ft). The measured length of sibiricum (from a nearly complete skeleton found at Gaevskaya) is 4.5 metres (15 ft). Extrapolation from the greater size of caucasicum molars obtains a length of 5 metres (16 ft)—5.2 metres (17 ft) for caucasicum. According to Legendre's formula, E. sibiricum had a mass of over 4,000 kilograms (3.9 long tons; 4.4 short tons); E. caucasicum, 5,000 kilograms (4.9 long tons; 5.5 short tons). These weights place Elasmotherium in the "really huge" category of all Rhinocerotidae and therefore the animal was "strongly brachyopodial;" that is, they required feet of large contact area to prevent sinking into the soil. The feet were unguligrade, the front larger than the rear: purely tridactyl on Digits II-IV in the rear, but with an extra vestigial digit, I, in the front.
Ankylosaurus (which is pronounced /ˌæŋkɨlɵˈsɔrəs/ [ANG-ki-lo-SAWR-us] or /æŋˌkaɪlɵˈsɔrəs/ [ang-KIE-lo-SAWR-us], and which means "fused lizard") is a genus of ankylosaurid dinosaur, containing one species, A. magniventris. Fossils of Ankylosaurus are found in geologic formations dating to the very end of the Cretaceous Period (about 66.5–65.5 Ma ago) in western North America. Although a complete skeleton has not been discovered and several other dinosaurs are represented by more extensive fossil material, Ankylosaurus is often considered the archetypal armored dinosaur. Other ankylosaurids shared its well-known features—the heavily-armored body and massive bony tail club—but Ankylosaurus was the largest known member of the family. In comparison with modern land animals the adult Ankylosaurus was very large. Some scientists have estimated a length of 9 meters (30 ft). Another reconstruction suggests a significantly smaller size, at 6.25 m (20.5 ft) long, up to 1.5 m (5 ft) wide and about 1.7 m (5.5 ft) high at the hip. Ankylosaurus may have weighed over 6,000 kilograms (13,000 lb), making it one of the heaviest armored dinosaurs yet discovered. The body shape was low-slung and quite wide. It was quadrupedal, with the hind limbs longer than the forelimbs. Although its feet are still unknown, comparisons with other ankylosaurids suggest Ankylosaurus probably had five toes on each foot. The skull was low and triangular in shape, wider than it was long. The largest known skull measures 64.5 centimeters (25 in) long and 74.5 cm (29 in) wide. Like other ankylosaurs, Ankylosaurus was herbivorous, with small, leaf-shaped teeth suitable for cropping vegetation. These teeth were smaller, relative to the body size, than in any other ankylosaurid species. Ankylosaurus did not share the grinding tooth batteries of the contemporaneous ceratopsid and hadrosaurid dinosaurs, indicating that very little chewing occurred. Bones in the skull and other parts of the body were fused, increasing their strength.
Steppe Rhinoceros - Elasmotherium sibiricum
Elasmotherium ("Thin Plate Beast") is an extinct genus of giant rhinoceros endemic to Eurasia during the Late Pliocene through the Pleistocene, documented from 2.6 mya to as late as 50,000 years ago, possibly later, in the Late Pleistocene, an approximate span of slightly less than 2.6 million years. Three species are recognised. The best known, E. sibiricum was the size of a mammoth and is thought to have borne a large, thick horn on its forehead which was used for defense, attracting mates, driving away competitors, sweeping snow from the grass in winter and digging for water and plant roots. Like all rhinoceroses, elasmotheres were herbivorous. Unlike any others, its high-crowned molars were ever-growing. Its legs were longer than those of other rhinos and were designed for galloping, giving it a horse-like gait. The Russian paleontologists of the 19th century who discovered and named the initial fossils were influenced by ancient legends of a huge unicorn roaming the steppes of Siberia. To date no evidence either contradicts or confirms the possibility that Elasmotherium survived into legendary times. The most reconstructed species is perhaps E. sibiricum by generations of scientists working at the Paleontological Museum in Moscow and elsewhere in Russia. The majority of the fossils fall or have fallen within their national jurisdiction. The dimensions and morphology of the various reconstructions vary considerably. They are for the most part estimating the gross details from the minutiae. However, they all agree on the general order of magnitude, that sibiricum was comparable to a Mammoth and was rather larger than the contemporary Woolly Rhinoceros. E. sibiricum had a measured shoulder height of approximately 2 metres (6.6 ft). To it, however, must be added the height of a massive hump anchored on the fin-like transverse processes extending from the top of the cervical vertebrae, a maximum of 53 centimetres (1.74 ft). The total height then was in excess of 253 centimetres (8.30 ft). The measured length of sibiricum (from a nearly complete skeleton found at Gaevskaya) is 4.5 metres (15 ft). Extrapolation from the greater size of caucasicum molars obtains a length of 5 metres (16 ft)—5.2 metres (17 ft) for caucasicum. According to Legendre's formula, E. sibiricum had a mass of over 4,000 kilograms (3.9 long tons; 4.4 short tons); E. caucasicum, 5,000 kilograms (4.9 long tons; 5.5 short tons). These weights place Elasmotherium in the "really huge" category of all Rhinocerotidae and therefore the animal was "strongly brachyopodial;" that is, they required feet of large contact area to prevent sinking into the soil. The feet were unguligrade, the front larger than the rear: purely tridactyl on Digits II-IV in the rear, but with an extra vestigial digit, I, in the front.
