Friday, 15 November 2013
5 Of The Most Amazing Extinct Animals
1. Tyrannosaurus Rex (extinct 65 million years ago) [Wiki]
Tyrannosaurus rex was one of the largest land carnivores of all time,
measuring up to 43.3 feet long, and 16.6 ft tall, with an estimated mass
that goes up to 7 tons. Like other tyrannosaurids, Tyrannosaurus was a
bipedal carnivore with a massive skull balanced by a long, heavy tail.
Relative to the large and powerful hindlimbs, Tyrannosaurus forelimbs
were small and they retained only two digits.
Fossils of T. rex have been found in North American rock formations dating to the last three million years of the Cretaceous Period at the end of the Maastrichtian stage, approximately 68.5 to 65.5 million years ago; it was among the last dinosaurs to exist prior to the Cretaceous-Tertiary extinction event. More than 30 specimens of T. rex have been identified, some of which are nearly complete skeletons. Some researchers have discovered soft tissue as well. The abundance of fossil material has allowed significant research into many aspects of its biology, including life history and biomechanics.
Fossils of T. rex have been found in North American rock formations dating to the last three million years of the Cretaceous Period at the end of the Maastrichtian stage, approximately 68.5 to 65.5 million years ago; it was among the last dinosaurs to exist prior to the Cretaceous-Tertiary extinction event. More than 30 specimens of T. rex have been identified, some of which are nearly complete skeletons. Some researchers have discovered soft tissue as well. The abundance of fossil material has allowed significant research into many aspects of its biology, including life history and biomechanics.
2. Quagga: half zebra, half horse (extinct since 1883) [Wiki]
One of Africa's most famous extinct animals, the quagga was a subspecies
of the plains zebra, which was once found in great numbers in South
Africa's Cape Province and the southern part of the Orange Free State.
It was distinguished from other zebras by having the usual vivid marks
on the front part of the body only. In the mid-section, the stripes
faded and the dark, inter-stripe spaces became wider, and the
hindquarters were a plain brown. The name comes from a Khoikhoi word for
zebra and is onomatopoeic, being said to resemble the quagga's call.
The quagga was originally classified as an individual species, Equus quagga, in 1788. Over the next fifty years or so, many other zebras were described by naturalists and explorers. Because of the great variation in coat patterns (no two zebras are alike), taxonomists were left with a great number of described "species", and no easy way to tell which of these were true species, which were subspecies, and which were simply natural variants. Long before this confusion was sorted out, the quagga had been hunted to extinction for meat, hides, and to preserve feed for domesticated stock. The last wild quagga was probably shot in the late 1870s, and the last specimen in captivity died on August 12, 1883 at the Artis Magistra zoo in Amsterdam.
Because of the great confusion between different zebra species, particularly among the general public, the quagga had become extinct before it was realized that it appeared to be a separate species. The quagga was the first extinct creature to have its DNA studied. Recent genetic research at the Smithsonian Institution has demonstrated that the quagga was in fact not a separate species at all, but diverged from the extremely variable plains zebra.
The quagga was originally classified as an individual species, Equus quagga, in 1788. Over the next fifty years or so, many other zebras were described by naturalists and explorers. Because of the great variation in coat patterns (no two zebras are alike), taxonomists were left with a great number of described "species", and no easy way to tell which of these were true species, which were subspecies, and which were simply natural variants. Long before this confusion was sorted out, the quagga had been hunted to extinction for meat, hides, and to preserve feed for domesticated stock. The last wild quagga was probably shot in the late 1870s, and the last specimen in captivity died on August 12, 1883 at the Artis Magistra zoo in Amsterdam.
Because of the great confusion between different zebra species, particularly among the general public, the quagga had become extinct before it was realized that it appeared to be a separate species. The quagga was the first extinct creature to have its DNA studied. Recent genetic research at the Smithsonian Institution has demonstrated that the quagga was in fact not a separate species at all, but diverged from the extremely variable plains zebra.
3. Irish Deer: the largest deer that ever lived (extinct about 7,700 years ago) [Wiki - Photo: (c) The Field Museum, CK1T]
The Irish Elk or Giant Deer, was the largest deer that ever lived. It
lived in Eurasia, from Ireland to east of Lake Baikal, during the Late
Pleistocene and early Holocene. The latest known remains of the species
have been carbon dated to about 5,700 BC, or about 7,700 years ago. The
Giant Deer is famous for its formidable size (about 2.1 meters or 7 feet
tall at the shoulders), and in particular for having the largest
antlers of any known cervid (a maximum of 3.65 meters/12 feet from tip
to tip and weighing up to 90 pounds).
Discussion of the cause of their extinction has still focused on the antlers (rather than on their overall body size), which may be due more to their impact on the observer than any actual property. Some have suggested hunting by man was a contributing factor in the demise of the Irish Elk as it was with many prehistoric megafauna, even assuming that the large antler size restricted the movement of males through forested regions or that it was by some other means a "maladaptation". But evidence for overhunting is equivocal, and as a continental species, it would have co-evolved with humans throughout its existence and presumably have adapted to their
Discussion of the cause of their extinction has still focused on the antlers (rather than on their overall body size), which may be due more to their impact on the observer than any actual property. Some have suggested hunting by man was a contributing factor in the demise of the Irish Elk as it was with many prehistoric megafauna, even assuming that the large antler size restricted the movement of males through forested regions or that it was by some other means a "maladaptation". But evidence for overhunting is equivocal, and as a continental species, it would have co-evolved with humans throughout its existence and presumably have adapted to their
4. Caspian Tiger: the third largest (extinct since 1970) [Wiki]
The Caspian tiger or Persian tiger was the westernmost subspecies of
tiger, found in Iran, Iraq, Afghanistan, Turkey, Mongolia, Kazakhstan,
Caucasus, Tajikistan, Turkmenistan and Uzbekistan until it apparently
became extinct in the 1970s. Of all the tigers known to the world, the
Caspian tiger was the third largest.
The body of this subspecies was quite stocky and elongated with strong legs, big wide paws and unusually large claws. The ears were short and small, and gave the appearance of being without hair on the tips. Around the cheeks the Caspian tiger was generously furred and the rest of its fur was long and thick. The colouration resembled that of the Bengal tiger. Male Caspian tigers were very large and weighed 169-240 kg. Females were not as large, weighing 85-135 kg. There are still occasional claims of the Caspian tiger being sighted.
The body of this subspecies was quite stocky and elongated with strong legs, big wide paws and unusually large claws. The ears were short and small, and gave the appearance of being without hair on the tips. Around the cheeks the Caspian tiger was generously furred and the rest of its fur was long and thick. The colouration resembled that of the Bengal tiger. Male Caspian tigers were very large and weighed 169-240 kg. Females were not as large, weighing 85-135 kg. There are still occasional claims of the Caspian tiger being sighted.
5. Aurochs: a very large type of cattle (extinct since 1627) [Wiki]
One of Europe's most famous extinct animals, the aurochs or urus (Bos
primigenius) were a very large type of cattle. Aurochs evolved in India
some two million years ago, migrated into the Middle East and further
into Asia, and reached Europe about 250,000 years ago.
By the 13th century A.D., the aurochs' range was restricted to Poland,
Lithuania, Moldavia, Transylvania and East Prussia. The right to hunt
large animals on any land was restricted to nobles and gradually to the
royal household. As the population of aurochs declined, hunting ceased
but the royal court still required gamekeepers to provide open fields
for the aurochs to graze in. The gamekeepers were exempted from local
taxes in exchange for their service and a decree made poaching an
aurochs punishable by death. In 1564, the gamekeepers knew of only 38
animals, according to the royal survey. The last recorded live aurochs, a
female, died in 1627 in the Jaktorów Forest, Poland. The skull was
later taken by the Swedish Army and is now the property of
Livrustkammaren in Stockholm.
In the 1920s two German zookeepers, the brothers Heinz and Lutz Heck,
attempted to breed the aurochs back into existence (see breeding back)
from the domestic cattle that were their descendants. Their plan was
based on the conception that a species is not extinct as long as all its
genes are still present in a living population. The result is the breed
called Heck Cattle, 'Recreated Aurochs', or 'Heck Aurochs', which bears
an incomplete resemblance to what is known about the physiology of the
wild aurochs
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