Post by DinosaurMichael on Jun 29, 2013 5:28:13 GMT 5
Saltwater Crocodile - Crocodylus porosus
The saltwater crocodile, also known as estuarine or Indo-Pacific crocodile, (Crocodylus porosus) is the largest of all living reptiles. It is found in suitable habitats in Northern Australia, the eastern coast of India and parts of Southeast Asia. The saltwater crocodile has a longer muzzle than the mugger crocodile: its length is twice its breadth at the base. The saltwater crocodile has fewer armor plates on its neck than other crocodilians, and its broad body contrasts with that of most other lean crocodiles, leading to early unverified assumptions that the reptile was an alligator. Saltwater crocodile skull from The Museum of Zoology, Saint PetersburgNewly hatched saltwater crocodiles measure about 25 to 30 centimetres (9.8–12 in) long and weigh an average of 70 grams (2.5 oz). Males reach sexual maturity at around 3.3 metres (11 ft) at around 16 years of age, while females reach sexual maturity at 2.1 metres (6.9 ft) and 12–14 years. An adult male saltwater crocodile's weight is 409 to 1,000 kilograms (900–2,200 lb) and length is normally 4.1 to 5.5 metres (13–18 ft). However, mature males can exceed 6 metres (20 ft) and weigh more than 1,000 kilograms (2,200 lb) and this species is the only extant crocodilian to regularly reach or exceed 4.8 metres (16 ft). Weight can vary enormously based upon condition and age, older males tending to outweigh younger ones since they maintain prime territories with access to better, more abundant prey. For example, crocodiles at 4.8 metres (16 ft) long have ranged in mass variously from 522 kilograms (1,150 lb) to 1,000 kilograms (2,200 lb). This species has the greatest sexual dimorphism of any modern crocodilian, with females being much smaller than males. Typical female body lengths in the range of 2.3 to 3.5 metres (8–11 ft). The largest female on record measured about 4.2 metres (14 ft). The mean weight of the species as a whole is roughly 450 kilograms (1,000 lb). Saltwater crocodile outside Cairns, QueenslandThe largest size saltwater crocodiles can reach is the subject of considerable controversy. The longest crocodile ever measured snout-to-tail and verified was the skin of a dead crocodile, which was 6.2 metres (20 ft) long. As skins tend to shrink slightly after removal from the carcass, this crocodile's living length was estimated at 6.3 metres (21 ft), and it could have weighed more than 1,000 kilograms (2,200 lb). Incomplete remains (the skull of a crocodile shot in Orissa) have been claimed to come from a 7.6-metre (25 ft) crocodile, but scholarly examination suggested a length no greater than 7 metres (23 ft). There have been numerous claims of crocodiles in the 9-metre (30 ft) range: the crocodile shot in the Bay of Bengal in 1840, reported at 10 metres (33 ft); another killed in 1823 at Jalajala on the main island of Luzon in the Philippines reported at 8.2 metres (27 ft); a reported 7.6 metres (25 ft) crocodile killed in the Hooghly River in the Alipore District of Calcutta. However, examinations of these animals' skulls actually indicated animals ranging from 6 to 6.6 metres (20–21.7 ft). A crocodile shot in Queensland in 1957 was reported to be 8.63 metres (28.3 ft) long, but no verified measurements were made and no remains of this crocodile exist. A "replica" of this crocodile has been made as a tourist attraction. Many other unconfirmed reports of crocodiles exceeding 8 metres (28+ ft) have been made but these are highly unlikely. With recent restoration of saltwater crocodile habitat and reduced poaching, it is possible that 7-metre (23 ft) crocodiles are alive today. Guinness has accepted a claim of a 7-metre (23 ft), 2,000 kg (4,400 lb) male saltwater crocodile living within Bhitarkanika Park in the state of Orissa, India, although, due to the difficulty of trapping and measuring a very large live crocodile, the accuracy of these dimensions has yet to be verified.
Megalania - Varanus priscus
Megalania ("great roamer"; Greek
?? "great" + "roam") is a giant extinct goanna or monitor lizard. It was part of a megafaunal assemblage that inhabited southern Australia during the Pleistocene, and appears to have disappeared around 40,000 years ago. The first aboriginal settlers of Australia may have encountered living Megalania. The name Megalania prisca was coined by Sir Richard Owen to mean "Ancient Great Roamer"; the name was intended to "reference to the terrestrial nature of the great Saurian". Owen used a modification of the Greek word ?lain? ("I roam"). The close similarity to the Latin word: lania (feminine form of "butcher") has resulted in numerous taxonomic and popular descriptions of Megalania mistranslating the name as: Ancient Giant Butcher. Megalania prisca was originally classified in its own monotypic genus. Its status as a valid genus remains controversial, with many authors preferring to consider it a junior synonym of Varanus, which encompasses all living monitor lizards. As the gender of the genera Megalania and Varanus are different (feminine and masculine, respectively), the epithet prisca changes to priscus (in alignment with the Code of the ICZN). Several studies have attempted to establish the phylogenetic position of Megalania within the Varanidae. An affinity with the Perentie, Australia's largest living lizard, has been suggested based on skull-roof morphology. The most recent comprehensive study proposes a sister-taxon relationship with the Komodo dragon based on neurocranial similarities, with the Lace monitor as the closest living Australian relative. Conversely, the Perentie is considered more closely related to the Gould's and Argus monitors. The lack of complete, or nearly complete fossil skeletons has made it difficult to determine the exact dimensions of Megalania. Early estimates placed the length of the largest individuals at 7 metres (23 ft), with a maximum weight of approximately 600–620 kilograms (1,300–1,400 lb). However, more recent and more rigorous studies give very different results from one another. In 2002, Stephen Wroe determined that Megalania had a maximum length of 4.5 metres (15 ft) and a weight of 331 kilograms (730 lb), while its average length would have been around 3.5 metres (11 ft), and mean body weight would have been between 97–158 kilograms (210–350 lb). He concluded that the earlier estimates reaching lengths of 6 metres (20 ft) or more and a weight of several tons were exaggerations based upon flawed methodologies. However, Ralph Molnar in 2004 determined a range of potential sizes for Megalania (made by scaling up from dorsal vertebrae, after he determined a relationship between dorsal vertebrae length and total body length). If it had a long thin tail like the Lace monitor (Varanus varius), then it would have reached a length of 7.9 metres (26 ft), while if its tail-to-body proportions were more similar to that of the Komodo dragon, then a length of around 7 metres (23 ft) is more likely. Taking the maximal 7 m length, he estimated a weight of 1,940 kilograms (4,300 lb), with a leaner 320 kilograms (710 lb) being average.
The saltwater crocodile, also known as estuarine or Indo-Pacific crocodile, (Crocodylus porosus) is the largest of all living reptiles. It is found in suitable habitats in Northern Australia, the eastern coast of India and parts of Southeast Asia. The saltwater crocodile has a longer muzzle than the mugger crocodile: its length is twice its breadth at the base. The saltwater crocodile has fewer armor plates on its neck than other crocodilians, and its broad body contrasts with that of most other lean crocodiles, leading to early unverified assumptions that the reptile was an alligator. Saltwater crocodile skull from The Museum of Zoology, Saint PetersburgNewly hatched saltwater crocodiles measure about 25 to 30 centimetres (9.8–12 in) long and weigh an average of 70 grams (2.5 oz). Males reach sexual maturity at around 3.3 metres (11 ft) at around 16 years of age, while females reach sexual maturity at 2.1 metres (6.9 ft) and 12–14 years. An adult male saltwater crocodile's weight is 409 to 1,000 kilograms (900–2,200 lb) and length is normally 4.1 to 5.5 metres (13–18 ft). However, mature males can exceed 6 metres (20 ft) and weigh more than 1,000 kilograms (2,200 lb) and this species is the only extant crocodilian to regularly reach or exceed 4.8 metres (16 ft). Weight can vary enormously based upon condition and age, older males tending to outweigh younger ones since they maintain prime territories with access to better, more abundant prey. For example, crocodiles at 4.8 metres (16 ft) long have ranged in mass variously from 522 kilograms (1,150 lb) to 1,000 kilograms (2,200 lb). This species has the greatest sexual dimorphism of any modern crocodilian, with females being much smaller than males. Typical female body lengths in the range of 2.3 to 3.5 metres (8–11 ft). The largest female on record measured about 4.2 metres (14 ft). The mean weight of the species as a whole is roughly 450 kilograms (1,000 lb). Saltwater crocodile outside Cairns, QueenslandThe largest size saltwater crocodiles can reach is the subject of considerable controversy. The longest crocodile ever measured snout-to-tail and verified was the skin of a dead crocodile, which was 6.2 metres (20 ft) long. As skins tend to shrink slightly after removal from the carcass, this crocodile's living length was estimated at 6.3 metres (21 ft), and it could have weighed more than 1,000 kilograms (2,200 lb). Incomplete remains (the skull of a crocodile shot in Orissa) have been claimed to come from a 7.6-metre (25 ft) crocodile, but scholarly examination suggested a length no greater than 7 metres (23 ft). There have been numerous claims of crocodiles in the 9-metre (30 ft) range: the crocodile shot in the Bay of Bengal in 1840, reported at 10 metres (33 ft); another killed in 1823 at Jalajala on the main island of Luzon in the Philippines reported at 8.2 metres (27 ft); a reported 7.6 metres (25 ft) crocodile killed in the Hooghly River in the Alipore District of Calcutta. However, examinations of these animals' skulls actually indicated animals ranging from 6 to 6.6 metres (20–21.7 ft). A crocodile shot in Queensland in 1957 was reported to be 8.63 metres (28.3 ft) long, but no verified measurements were made and no remains of this crocodile exist. A "replica" of this crocodile has been made as a tourist attraction. Many other unconfirmed reports of crocodiles exceeding 8 metres (28+ ft) have been made but these are highly unlikely. With recent restoration of saltwater crocodile habitat and reduced poaching, it is possible that 7-metre (23 ft) crocodiles are alive today. Guinness has accepted a claim of a 7-metre (23 ft), 2,000 kg (4,400 lb) male saltwater crocodile living within Bhitarkanika Park in the state of Orissa, India, although, due to the difficulty of trapping and measuring a very large live crocodile, the accuracy of these dimensions has yet to be verified.
Megalania - Varanus priscus
Megalania ("great roamer"; Greek
?? "great" + "roam") is a giant extinct goanna or monitor lizard. It was part of a megafaunal assemblage that inhabited southern Australia during the Pleistocene, and appears to have disappeared around 40,000 years ago. The first aboriginal settlers of Australia may have encountered living Megalania. The name Megalania prisca was coined by Sir Richard Owen to mean "Ancient Great Roamer"; the name was intended to "reference to the terrestrial nature of the great Saurian". Owen used a modification of the Greek word ?lain? ("I roam"). The close similarity to the Latin word: lania (feminine form of "butcher") has resulted in numerous taxonomic and popular descriptions of Megalania mistranslating the name as: Ancient Giant Butcher. Megalania prisca was originally classified in its own monotypic genus. Its status as a valid genus remains controversial, with many authors preferring to consider it a junior synonym of Varanus, which encompasses all living monitor lizards. As the gender of the genera Megalania and Varanus are different (feminine and masculine, respectively), the epithet prisca changes to priscus (in alignment with the Code of the ICZN). Several studies have attempted to establish the phylogenetic position of Megalania within the Varanidae. An affinity with the Perentie, Australia's largest living lizard, has been suggested based on skull-roof morphology. The most recent comprehensive study proposes a sister-taxon relationship with the Komodo dragon based on neurocranial similarities, with the Lace monitor as the closest living Australian relative. Conversely, the Perentie is considered more closely related to the Gould's and Argus monitors. The lack of complete, or nearly complete fossil skeletons has made it difficult to determine the exact dimensions of Megalania. Early estimates placed the length of the largest individuals at 7 metres (23 ft), with a maximum weight of approximately 600–620 kilograms (1,300–1,400 lb). However, more recent and more rigorous studies give very different results from one another. In 2002, Stephen Wroe determined that Megalania had a maximum length of 4.5 metres (15 ft) and a weight of 331 kilograms (730 lb), while its average length would have been around 3.5 metres (11 ft), and mean body weight would have been between 97–158 kilograms (210–350 lb). He concluded that the earlier estimates reaching lengths of 6 metres (20 ft) or more and a weight of several tons were exaggerations based upon flawed methodologies. However, Ralph Molnar in 2004 determined a range of potential sizes for Megalania (made by scaling up from dorsal vertebrae, after he determined a relationship between dorsal vertebrae length and total body length). If it had a long thin tail like the Lace monitor (Varanus varius), then it would have reached a length of 7.9 metres (26 ft), while if its tail-to-body proportions were more similar to that of the Komodo dragon, then a length of around 7 metres (23 ft) is more likely. Taking the maximal 7 m length, he estimated a weight of 1,940 kilograms (4,300 lb), with a leaner 320 kilograms (710 lb) being average.
