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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.





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.




Thylacine: the Tasmanian Tiger (extinct since 1936) [Wiki]
The
Thylacine was the largest known carnivorous marsupial of modern times.
Native to Australia and New Guinea, it is thought to have become extinct
in the 20th century. It is commonly known as the Tasmanian Tiger (due
to its striped back), and also known as the Tasmanian Wolf, and
colloquially the Tassie (or Tazzy) Tiger or simply the Tiger. It was the
last extant member of its genus, Thylacinus, although a number of
related species have been found in the fossil record dating back to the
early Miocene.

The Thylacine became extinct on the Australian
mainland thousands of years before European settlement of the continent,
but survived on the island of Tasmania along with a number of other
endemic species such as the Tasmanian Devil. Intensive hunting
encouraged by bounties is generally blamed for its extinction, but other
contributory factors may have been disease, the introduction of dogs,
and human encroachment into its habitat. Despite being officially
classified as extinct, sightings are still reported.