EXTINCT SPECIES

Dire Wolf (Canis Dirus)

‘Canis Dirus’ means ‘terrible wolf’ in Latin, and this species certainly lived up to its name. It is one of the prehistoric animals which lived in North America, along with its extinct competitor, the Smilodon. The dire Wolf lived in the Americas and eastern Asia during the Late Pleistocene and Early Holocene epochs. The first dire Wolf fossils were found in 1854 from the Ohio River in Indiana. These animals always hunted in packs like modern wolves. When hunting, the wolf pack separated out and surrounded the pret. They usually bit the shoulders and flanks. While some pack members approached the prey from the rear, other wolves seized the prey by the nose. The dire wolf was the largest of the Late Pleistocene canids of North America. The skull could reach up to 12 inches in length and it's teeth were larger and more robust than today’s grey wolves.

Plesiosaur (Plesiosauria)

Maybe this looks like a dinosaur with flippers instead of legs, kind of like a dino-whale hybrid. So, don’t be surprised when I say this was not a dinosaur. The Plesiosauria or Plesiosauria are an order or clade of extinct Mesozoic marine reptiles, not dinosaurs. They belong to the Sauropterygia. Plesiosaurs first appeared in the latest Triassic Period, possibly in the Rhaetian stage, about 203 million years ago. They lived in a wide range of environments from near-shore estuaries to the open ocean, and some even lived in freshwater habitats. Plesiosaurs came in all shapes and sizes, ranging from as big as a whale to smaller than an average porpoise, and had equally diverse diets. One of the largest is known as the Australian giant Kronosaurus, which measured in at 10-11 metres (33-36 feet) long. The new Norwegian find, named “The Monster” by team members, is estimated to be about 15 meters (50 feet) long, making it one of the longest and most massive plesiosaurs yet found. There are other marine reptiles, such as ichthyosaurs, pliosaurs and mosasaurs, and they are not dinosaurs. Nor is Dimetrodon or other reptiles in the same group (previously called ‘mammal-like reptiles’ and now called synapsids). None of these other extinct groups shared the characteristic upright stance of dinosaurs, yet they are still one of the most terrifying creatures which are extinct.

Megalodon (Otodus Megalodon)

Megalodon, meaning “big tooth”, is an extinct species of mackerel shark that lived approximately 23 to 3.6 million years ago, from the Early Miocene to the Pliocene epochs. It was formerly thought to be a member of the family Lamnidae and a close relative of the Great White Shark (Carcharodon carcharias). However, it is now classified into the extinct family Otodontidae, which diverged from the Great White Shark during the Early Cretaceous. While regarded as one of the largest and most powerful predators to have ever lived, the Megalodon is only known from fragmentary remains, and it's appearance and maximum size are uncertain. Scientist differs on whether it would have more closely resembled as a stockier version of the Great White Shark, the Whale Shark, the Basking Shark or the Sand Tiger Shark. The most recent estimate suggests a maximum length estimate up to 20.3 meters (67 ft), although the modal lengths are estimated at 10.5 meters (34 ft). The Megalodon probably had a major impact on the structure of marine communities. The fossil record indicated that it had a cosmopolitan distribution. It probably targeted large prey, such as whales, seals and sea turtles. Unlike the Great White Shark, which attacks prey from the soft underside, Megalodon probably used it's strong jaws to break through the chest cavity and puncture the heart and lungs of its prey.

Aurochs (Bos Primigenius)

The aurochs (Bos primigenius) is an extinct cattle species, considered to be the wild ancestor of modern domestic cattle. With a shoulder height of up to 180 cm (71 in) in bulls and 155 cm (61 in) in cows, it was one of the largest herbivores in the Holocene; it had massive elongated and broad horns that reached 80 cm (31 in) in length. The aurochs was part of the Pleistocene megafauna. It probably evolved in Asia and migrated west and north during warm interglacial periods. The oldest known aurochs fossils found in India and North Africa date to the Middle Pleistocene and in Europe to the Holstein interglacial. As indicated by fossil remains in Northern Europe, it reached Denmark and southern Sweden during the Holocene. The aurochs declined during the late Holocene due to habitat loss and hunting, and became extinct when the last individual died in 1627 in Jaktorów forest in Poland. 

Thylacoleo (Thylacoleo carnifex)

Thylacoleo (pronounced thy-lack-OH-leo) is also called the “pouch lion” is an extinct genus of carnivorous marsupials that lived in Australia from the late Pliocene to the late Pleistocene (2 million to 46 thousand years ago). Some of these marsupial lions were the largest mammalian predators in Australia of their time, with Thylacoleo carnifex approaching the weight of a lioness. The first Thylacoleo fossil findings, discovered by Thomas Mitchell were found in the 1830s in the Wellington Valley of New South Wales, though not recognised as such at the time. The generic holotype, consisting of broken teeth, jaws, and a skull was discovered by a pastoralist, William Avery, near Lake Colungolac from which the species Thylacoleo carnifex was described by Richard Owen. It was not until 1966 that the first nearly-complete skeleton was found. The only pieces missing were a foot and the tail. Currently, the Nullarbor Plain of West Australia remains to be the greatest finding site. These fossils now reside at the Australian Museum.

Thylacine (Thylacinus cynocephalus)

The thylacine, also commonly known as the Tasmanian tiger or Tasmanian wolf, is an extinct carnivorous marsupial that was native to the Australian mainland and the islands of Tasmania and New Guinea. They had almost died out out on the Australian mainland from around 2,000 years ago, most likely because of the introduction of dingoes or due to climate change. Prior to European settlement around 5,000 remained in the wild on Tasmania. Beginning in the nineteenth century they were perceived as a threat to the livestock of farmers and bounty hunting was introduced. The last known of its species died in 1936 at Hobart Zoo in Tasmania. The thylacine is widespread in popular culture and is a cultural icon in Australia. Its closest living relatives are now dasyurid marsupials such as quolls and the Tasmanian Devil. Some sources suggest that there are ideas for genetic startups to bring back the species of thylacines.

Basilosaurus (Basilosaurus)

Now, last but not at all least, the Basilosaurus is one of the Top Ten Most Nightmarish Extinct Species on the list. The name Basilosaurus means “king lizard” (wow, even the name is impressive) and it is a genus of large, predatory, prehistoric archaeocete whale from the late Eocene, approximately 41.3 to 33.9 million years ago. First described in 1834, it was the first archaeocete and prehistoric whale known to science. Basilosaurus is thought to have been common in the Tethys Ocean. It was one of the largest, if not the largest, animals of the Paleogene. It was the top predator of its environment, preying on sharks, large fish and other marine mammals, namely the dolphin-like Dorudon, which seems to have been their predominant food source. Basilosaurus, unlike modern cetaceans, had various types of teeth– such as canines and molars– in its mouth (heterodonty) and it probably was able to chew its food in contrast to modern cetaceans which shallow their food whole. Abrupt global cooling of the Earth’s climate at the end of the Eocene coincided with the changing ocean circulation. This led to the extinction of Basilosaurus and most archaic whales around 34 million years ago.

Picture credits: Google