Irish Deer: the largest deer that ever lived (extinct about 7,700 years ago)
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 presence.
Caspian Tiger: the third largest (extinct since 1970)
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.
Aurochs: a very large type of cattle (extinct since 1627)
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
Great Auk: largest of all auks (extinct since 1844)
The Great Auk was the only species in the genus Pinguinus, flightless giant auks from the Atlantic, to survive until recent times, but is extinct today. It was also known as garefowl, or penguin.Standing about 75 centimetres or 30-34 inches high and weighing around 5 kg, the flightless Great Auk was the largest of the auks. It had white and glossy black feathers. In the past, the Great Auk was found in great numbers on islands off eastern Canada, Greenland, Iceland, Norway, Ireland and Great Britain, but it was eventually hunted to extinction. Remains found in Floridan middens suggest that at least occasionally, birds ventured that far south in winter as recently as in the 14th century.