Monday, February 1, 2010
"EXTINCT MAMMOTH." (Part 1)
"EXTINCT MAMMOTH." (Part 1)
Species: There were several species of extinct mammoths, such as M. africanavus (African mammoth), M. columbi (Columbian mammoth), M. subplanifrons (South African mammoth), M. primigenius (Woolly mammoth), M. sungari (Songhua River mammoth), etc.
A mammoth is any species of the extinct genus Mammuthus. These proboscideans are members of Elephantidae, the family of elephants and mammoths, and close relatives of modern elephants. They were often equipped with long curved tusks and, in northern species, a covering of long hair. They lived the Pliocene epoch from around 4.8 million to 4,500 years ago.
Like their modern relative the elephant, mammoths were quite large; in English the noun "mammoth" has become an adjective meaning "huge" or "massive". The largest known species, Songhua River Mammoth (Mammuthus sungari), reached heights of at least 5 meters (16 feet) at the shoulder. Mammoths would probably normally weigh in the region of 6 to 8 tons, but exceptionally large males may have exceeded 12 tons. An 11-foot (3.4 m) long mammoth tusk was discovered north of Lincoln, Illinois in 2005. However, most species of mammoth were only about as large as a modern Asian Elephant. Fossils of species of dwarf mammoth have been found on the Californian Channel Islands (Mammuthus exilis) and the Mediterranean island of Sardinia (Mammuthus lamarmorae). There was also a race of dwarf woolly mammoths on Wrangel Island, north of Siberia, Russia, within the Arctic Circle.
Based on studies of their close relatives the modern elephants, mammoths probably had a gestation period of 22 months, resulting in a single calf being born. Their social structure was probably the same as that of African and Asian elephants, with females living in herds headed by a matriarch, whilst bulls lived solitary lives or formed loose groups after sexual maturity.
There is an estimate of 150 million mammoth remains in Russia´s Siberian permafrost, which covers a vast area sparsely inhabited areas. Some of the remains are frozen complete, others in pieces of bone, tusk, tissue and wool, in less a metre below ground to 1 km. below.
The woolly mammoth was the last species of the genus. Most populations of the woolly mammoth in North America and Eurasia, as well all the Columbian mammoths in North America, died around the time of the last glacial retreat, as part of a mass extinction of megafauna in northern Eurasia and the Americas. Until recently, it was generally assumed that the last woolly mammoths vanished from Europe and southern Siberia about 10,000 BC, but new findings show that some were still present there about 8,000 BC. Only slightly later, the woolly mammoths also disappeared from continental northern Siberia. A small population survived on St. Paul Island, Alaska, up until 3,750 BC., and the small mammoths of Wrangel Island survived until 1,650 BC.
A definite explanation for their mass extinction is yet to be agreed upon. The warming trend that occurred 12,000 years ago, accompanied by a glacial retreat and rising sea levels, has been suggested as a contributing factor. Forests replaced open woodlands and grasslands across the continent. The available habitat may have been reduced for some megafaunal species, such as the mammoth. However, such climate changes were nothing new; numerous very similar warming episodes had occurred previously within the ice age of the last several million years without producing comparable megafaunal extinctions, so climate alone is unlikely to have played a decisive role. The spread of advanced human hunters through northern Eurasia and the Americas around the time of the extinctions was a new development, and thus probably contributed significantly.
Whether the general mammoth population died out for climatic reasons or due to overhunting by humans is controversial. Another theory suggests that mammoths may have fallen victim to an infectious disease. A combination of climate change and hunting by humans has been suggested as the most likely explanation for their extinction.
Data derived from studies done on living elephants suggests human hunting was likely a strong contributing factor in the mammoth´s final extinction.
HOMO ERECTUS is known to have consumed mammoth meat as early as 1.8 million years ago.
INFORMATION ABOUT OZONE LAYER, GLOBAL WARMING, THE RAIN FOREST AND EARTHQUAKE WILL FOLLOW THE SUBJECT OF EXTINCT MAMMOTH.
Thank you for reading!!