Exploring Prehistoric Life

What are Therapsids?

Tuesday, June 20, 2017

Lystrosaurus: is an extinct genus of dicinodontos therapsid Triassic period

Therapsida is a group of synapsids that includes mammals and their ancestors. Many of the traits today seen as unique to mammals had their origin within early therapsids, including having their four limbs extend vertically beneath the body, as opposed to the sprawling posture of other reptiles. The earliest fossil attributed to Therapsida is Tetraceratops insignis from the Lower Permian.

Therapsids evolved from pelycosaurs (specifically sphenacodonts) 275 million years ago. They replaced the pelycosaurs as the dominant large land animals in the Middle Permian and were replaced, in turn, by the archosauromorphs in the Triassic, although one group of therapsids, the kannemeyeriiforms, remained diverse in the Late Triassic.

The therapsids included the cynodonts, the group that gave rise to mammals in the Late Triassic around 225 million years ago. Of the non-mammalian therapsids, only cynodonts and dicynodonts survived the Triassic–Jurassic extinction event. The last of the non-mammalian therapsids, the tritylodontid cynodonts, became extinct in the Early Cretaceous, approximately 100 million years ago.

Mounted skeleton of Inostrancevia alexandri, a gorgonopsian therapsid

Legs and feet

Therapsid legs were positioned more vertically beneath their bodies than were the sprawling legs of reptiles and pelycosaurs. Also compared to these groups, the feet were more symmetrical, with the first and last toes short and the middle toes long, an indication that the foot’s axis was placed parallel to that of the animal, not sprawling out sideways. This orientation would have given a more mammal-like gait than the lizard-like gait of the pelycosaurs.

Jaw and teeth

Therapsids’ temporal fenestrae were larger than those of the pelycosaurs. The jaws of some therapsids were more complex and powerful, and the teeth were differentiated into frontal incisors for nipping, great lateral canines for puncturing and tearing, and molars for shearing and chopping food.

Fur and endothermy

Several characteristics in therapsids have been noted as being consistent with the development of endothermy: the presence of turbinates, erect limbs, highly vascularized bones, limb and tail proportions conducive to the preservation of body heat, and the absence of growth rings in bones. Therefore, like modern mammals, non-mammalian therapsids were most likely warm-blooded.

Recent studies on Permian coprolites showcase that hair was present in at least some therapsids. Hair is by any means present in the docodont Castorocauda and haramiyidan Megaconus, and whiskers are inferred from therocephalians and cynodonts.

Source: NatGeo.com, wikipedia.org

Top 5 Worst Mass Extinctions

Tuesday, June 20, 2017

Information and Facts About Mass Extinctions -  National Geographic

Ordovician-Silurian extinctionglobal extinction event occurring during the Hirnantian Age (445.2 million to 443.8 million years ago) of the Ordovician Period and the subsequent Rhuddanian Age (443.8 million to 440.8 million years ago) of the Silurian Period that eliminated an estimated 85 percent of all Ordovician species. This extinction interval ranks second in severity to the one that occurred at the boundary between the Permian and Triassic periods about 251 million years ago in terms of the percentage of marine families affected. The Ordovician-Silurian extinction was almost twice as severe as the K–T extinction event that occurred at the end of the Cretaceous Period, about 66 million years ago, which is famous for bringing an end to the dinosaurs.

via Futurism.com

The Late Devonian extinction was one of five major extinction events in the history of the Earth’s biota. A major extinction, the Kellwasser event, occurred at the boundary that marks the beginning of the last phase of the Devonian period, the Famennian faunal stage (the Frasnian–Famennian boundary), about 375–360 million years ago. Overall, 19% of all families and 50% of all genera became extinct. A second, distinct mass extinction, the Hangenberg event, closed the Devonian period.

via Futurism.com

The Permian–Triassic (P–Tr or P–Textinction event, colloquially known as the Great Dying, the End-Permian Extinction or the Great Permian Extinction, occurred about 252 Ma (million years) ago, forming the boundary between the Permian and Triassic geologic periods, as well as the Paleozoic and Mesozoic eras. It is the Earth’s most severe known extinction event, with up to 96% of all marine species and 70% of terrestrial vertebrate species becoming extinct. It is the only known mass extinction of insects. Some 57% of all families and 83% of all genera became extinct. Because so much biodiversity was lost, the recovery of life on Earth took significantly longer than after any other extinction event, possibly up to 10 million years. Studies in Bear Lake County near Paris, Idaho showed a quick and dynamic rebound in a marine ecosystem, illustrating the remarkable resiliency of life.

via Futurism.com

The Triassic–Jurassic extinction event marks the boundary between the Triassic and Jurassic periods, 201.3 million years ago, and is one of the major extinction events of the Phanerozoic eon, profoundly affecting life on land and in the oceans. In the seas, a whole class (conodonts) and 34% of marine genera disappeared. On land, all archosaurs other than crocodylomorphs (Sphenosuchia and Crocodyliformes) and Avemetatarsalia (pterosaurs and dinosaurs), some remaining therapsids, and many of the large amphibians became extinct.

via Futurism.com

The Cretaceous–Paleogene (K–Pgextinction event, also known as the Cretaceous–Tertiary (K–Textinction, was a mass extinction of some three-quarters of the plant and animal species on Earth that occurred over a geologically short period of time approximately 66 million years ago. With the exception of some ectothermic species like the leatherback sea turtle and crocodiles, no tetrapods weighing more than 25 kilograms (55 lb) survived. It marked the end of the Cretaceous period and with it, the entire Mesozoic Era, opening the Cenozoic Era that continues today.

via Futurism.com


 Sources: Futurism.com, Wikipedia.org, NatGeo.com, BBC.co.uk, Britannica.com

Woolly Mammoth

Monday, June 19, 2017

Woolly Mammoth Model at the Royal BC Museum

The woolly mammoth (Mammuthus primigenius) is a species of mammoth that lived during the Pleistocene epoch, and was one of the last in a line of mammoth species, beginning with Mammuthus subplanifrons in the early Pliocene. The woolly mammoth diverged from the steppe mammoth about 400,000 years ago in East Asia. Its closest extant relative is the Asian elephant. The appearance and behaviour of this species are among the best studied of any prehistoric animal because of the discovery of frozen carcasses in Siberia and Alaska, as well as skeletons, teeth, stomach contents, dung, and depiction from life in prehistoric cave paintings. Mammoth remains had long been known in Asia before they became known to Europeans in the 17th century. The origin of these remains was long a matter of debate, and often explained as being remains of legendary creatures. The mammoth was identified as an extinct species of elephant by Georges Cuvier in 1796.

Size (red) compared to a human and other mammoths

The woolly mammoth was roughly the same size as modern African elephants. Males reached shoulder heights between 2.7 and 3.4 m (8.9 and 11.2 ft) and weighed up to 6 tonnes (6.6 short tons). Females reached 2.6–2.9 m (8.5–9.5 ft) in shoulder heights and weighed up to 4 tonnes (4.4 short tons). A newborn calf weighed about 90 kilograms (200 lb). The woolly mammoth was well adapted to the cold environment during the last ice age. It was covered in fur, with an outer covering of long guard hairs and a shorter undercoat. The colour of the coat varied from dark to light. The ears and tail were short to minimise frostbite and heat loss. It had long, curved tusks and four molars, which were replaced six times during the lifetime of an individual. Its behaviour was similar to that of modern elephants, and it used its tusks and trunk for manipulating objects, fighting, and foraging. The diet of the woolly mammoth was mainly grass and sedges. Individuals could probably reach the age of 60. Its habitat was the mammoth steppe, which stretched across northern Eurasia and North America.

The woolly mammoth coexisted with early humans, who used its bones and tusks for making art, tools, and dwellings, and the species was also hunted for food. It disappeared from its mainland range at the end of the Pleistocene 10,000 years ago, most likely through climate change and consequent shrinkage of its habitat, hunting by humans, or a combination of the two. Isolated populations survived on St. Paul Island until 5,600 years ago and Wrangel Island until 4,000 years ago. After its extinction, humans continued using its ivory as a raw material, a tradition that continues today. It has been proposed the species could be recreated through cloning, but this method is as yet infeasible because of the degraded state of the remaining genetic material.

Like modern elephants, woolly mammoths were likely very social and lived in matriarchal (female-led) family groups. This is supported by fossil assemblages and cave paintings showing groups. It is therefore probable that most of their other social behaviour was similar to that of modern elephants. It is unknown how many mammoths lived at one location at a time, as fossil deposits are often accumulations of individuals that died over long periods of time. It is likely that the amounts varied by season and life-cycle events. Modern elephants can form large herds, sometimes consisting of multiple family groups, and these herds can include thousands of animals migrating together. Mammoths may have formed large herds more often, since animals that live in open areas are more likely to do this than those in forested areas. Trackways made by a woolly mammoth herd 11,300–11,000 years ago have been found in the St. Mary Reservoir in Canada, showing that there were in this case almost equal numbers of adults, sub-adults and juveniles. The adults had a stride of 2 m (6.6 ft), and the juveniles ran to keep up.


Source: NatGeo.com, Wikipedia.com


Sunday, June 18, 2017

Smilodon fatalis life-restoration

Smilodon is a genus of machairodont felid. It is one of the most famous prehistoric mammals, and the best known saber-toothed cat. Although commonly known as the saber-toothed tiger, it was not closely related to the tiger or other modern cats. Smilodon lived in the Americas during the Pleistocene epoch (2.5 mya–10,000 years ago). The genus was named in 1842, based on fossils from Brazil. Three species are recognized today: S. gracilisS. fatalis and S. populator. The two latter species were probably descended from S. gracilis, which itself probably evolved from Megantereon. The largest collection of Smilodon fossils has been obtained from the Rancho La Brea Tar Pits in Los Angeles, California.

S. populator (green), S. fatalis (purple), and S. gracilis (orange) shown to scale by Matthew Martyniuk

Smilodon was around the size of modern big cats, but was more robustly built. It had a reduced lumbar region, high scapula, short tail, and broad limbs with relatively short feet. Smilodon is most famous for its relatively long canine teeth, which are the longest found in the saber-toothed cats, at about 28 cm (11 in) long in the largest species, S. populator. The canines were slender and had fine serrations on the front and back side. The skull was robustly proportioned and the muzzle was short and broad. The cheek bones (zygomata) were deep and widely arched, the sagittal crest was prominent, and the frontal region was slightly convex. The mandible had a flange on each side of the front. The upper incisors were large, sharp, and slanted forwards.

S. populator skull and syntype canine from Lund’s collection, Zoological Museum, Copenhagen. Author: FunkMonk

Overall, Smilodon was more robustly built than any extant cat, with particularly well-developed forelimbs and exceptionally long upper canine teeth. Its jaw had a bigger gape than that of modern cats, and its upper canines were slender and fragile, being adapted for precision killing. S. gracilis was the smallest species at 55 to 100 kg (120 to 220 lb) in weight. S. fatalis had a weight of 160 to 280 kg (350 to 620 lb) and height of 100 cm (39 in). Both of these species are mainly known from North America, but remains from South America have also been attributed to them. S. populator from South America is perhaps the largest known felid at 220 to 400 kg (490 to 880 lb) in weight and 120 cm (47 in) in height. The coat pattern of Smilodon is unknown, but it has been artistically restored with plain or spotted patterns.

In North America, Smilodon hunted large herbivores such as bison and camels, and it remained successful even when encountering new prey species in South America. Smilodon is thought to have killed its prey by holding it still with its forelimbs and biting it, but it is unclear in what manner the bite itself was delivered. Scientists debate whether Smilodon had a social or a solitary lifestyle; analysis of modern predator behavior as well as of Smilodon‘s fossil remains could be construed to lend support to either view. Smilodon probably lived in closed habitats such as forests and bush, which would have provided cover for ambushing prey. Smilodon died out at the same time that most North and South American megafauna disappeared, about 10,000 years ago. Its reliance on large animals has been proposed as the cause of its extinction, along with climate change and competition with other species, but the exact cause is unknown.

Smilodon californicus fossil at the National Museum of Natural History, Washington, D.C. Author: Ryan Somma

Long the most completely known saber-toothed cat, Smilodon is still one of the best-known members of the group, to the point where the two concepts have been confused. The term “saber-tooth” refers to an ecomorph consisting of various groups of extinct predatory synapsids (mammals and close relatives), which convergently evolved extremely long maxillary canines, as well as adaptations to the skull and skeleton related to their use. This includes members of Gorgonopsia, Thylacosmilidae, Machaeroidinae, Nimravidae, Barbourofelidae, and Machairodontinae. Within the family Felidae (true cats), members of the subfamily Machairodontinae are referred to as saber-toothed cats, and this group is itself divided into three tribes: Metailurini (false saber-tooths); Homotherini (scimitar-toothed cats); and Smilodontini (dirk-toothed cats), to which Smilodon belongs. Members of Smilodontini are defined by their long slender canines with fine to no serrations, whereas Homotherini are typified by shorter, broad, and more flattened canines, with coarser serrations. Members of Metailurini were less specialized and had shorter, less flattened canines, and are not recognized as members of Machairodontinae by some researchers. 


The earliest felids are known from the Oligocene of Europe, such as Proailurus, and the earliest one with saber-tooth features is the Miocene genus Pseudaelurus. The skull and mandible morphology of the earliest saber-toothed cats was similar to that of the modern clouded leopards (Neofelis).

Along with most of the Pleistocene megafauna, Smilodon became extinct 10,000 years ago in the Quaternary extinction event. Its extinction has been linked to the decline and extinction of large herbivores, which were replaced by smaller and more agile ones like deer. Hence, Smilodon could have been too specialized at hunting large prey and may have been unable to adapt.  A 2012 study of Smilodon tooth wear found no evidence that they were limited by food resources. Other explanations include climate change and competition with humans (who entered the Americas around the time Smilodondisappeared), or a combination of several factors, all of which apply to the general Pleistocene extinction event, rather than specifically to the extinction of the saber-toothed cats.

Source: Wikipedia.com, NatGeo.com

Pleistocene Epoch

Wednesday, May 24, 2017

Pleistocene Epoch map

The Pleistocene Epoch is typically defined as the time period that began about 1.8 million years ago and lasted until about 11,700 years ago. The most recent Ice Age occurred then, as glaciers covered huge parts of the planet Earth.

There have been at least five documented major ice ages during the 4.6 billion years since the Earth was formed — and most likely many more before humans came on the scene about 2.3 million years ago.

The Pleistocene Epoch is the first in which Homo sapiens evolved, and by the end of the epoch humans could be found in nearly every part of the planet. The Pleistocene Epoch was the first epoch in the Quaternary Period and the sixth in the Cenozoic Era. It was followed by the current stage, called the Holocene Epoch.

Worldwide ice sheets

At the time of the Pleistocene, the continents had moved to their current positions. At one point during the Ice Age, sheets of ice covered all of Antarctica, large parts of Europe, North America, and South America, and small areas in Asia. In North America they stretched over Greenland and Canada and parts of the northern United States. The remains of glaciers of the Ice Age can still be seen in parts of the world, including Greenland and Antarctica.

But the glaciers did not just sit there. There was a lot of movement over time, and there were about 20 cycles when the glaciers would advance and retreat as they thawed and refroze. Scientists identified the Pleistocene Epoch’s four key stages, or ages — Gelasian, Calabrian, Ionian and Tarantian.

The name Pleistocene is the combination of two Greek words: pleistos (meaning “most”) and kainos (meaning “new” or “recent”). It was first used in 1839 by Sir Charles Lyell, a British geologist and lawyer.

As a result of Lyell’s work, the glacial theory gained acceptance between 1839 and 1846, and scientists came to recognize the existence of ice ages. During this period, British geologist Edward Forbes aligned the period with other known ice ages. In 2009, the International Union of Geological Sciences established the start of the Pleistocene Epoch at 1.806 million years before the present.

Defining an epoch

While scientists haven’t been able to determine the exact causes of an epoch, changes in ocean current, composition of the atmosphere, changes in the position of the Earth in relation to the sun are believed to be key contributors.

Overall, the climate was much colder and drier than it is today. Since most of the water on Earth’s surface was ice, there was little precipitation and rainfall was about half of what it is today. During peak periods with most of the water frozen, global average temperatures were 5 to 10 degrees C (9 to 18 degrees F) below today’s temperature norms.

There were winters and summers during that period. The variation in temperatures produced glacial advances, because the cooler summers didn’t completely melt the snow.

Life during the Ice Age

While Homo sapiens evolved, many vertebrates, especially large mammals, succumbed to the harsh climate conditions of this period.

One of the richest sources of information about life in the Pleistocene Epoch can be found in the La Brea Tar Pits in Los Angeles, where remains of everything from insects to plant life to animals were preserved, including a partial skeleton of a female human and a nearly complete woolly mammoth.

In addition to the woolly mammoth, mammals such as saber-toothed cats (Smilodon), giant ground sloths (Megatherium) and mastodons roamed the Earth during this period. Other mammals that thrived during this period include moonrats, tenrecs (hedgehog-like creatures) and macrauchenia (similar to a llamas and camels).

Although many vertebrates became extinct during this period, mammals that are familiar to us today — including apes, cattle, deer, rabbits, kangaroos, wallabies, bears, and members of the canine and feline families — could be found during this time.

Other than a few birds that were classified as dinosaurs, most notably the Titanis, there were no dinosaurs during the Pleistocene Epoch. They had become extinct at the end of the Cretaceous Period, more than 60 million years before the Pleistocene Epoch began.

Birds flourished during this period, including members of the duck, geese, hawk and eagle families. There were also some flightless birds such as ostriches, rheas and moas. The flightless birds did not fare as well, as they had to compete with mammals and other creatures for limited supplies of food and water, as a good portion of the water was frozen.

Crocodiles, lizards, turtles, pythons and other reptiles also thrived during this period.

As for vegetation, it was fairly limited in many areas. There were some scattered conifers, including pines, cypress and yews, along with some broadleaf trees such as beeches and oaks. On the ground, there were prairie grasses as well as members of the lilly, orchid and rose families.

Mass extinction

About 13,000 years ago, more than three-fourths of the large Ice Age animals, including woolly mammoths, mastodons, saber-toothed tigers and giant bears, died out.  Scientists have debated for years over the cause of the extinction, with both of the major hypotheses — human overhunting and climate change — insufficient to account for the mega die-off.

Recent research suggests that an extraterrestrial object, possibly a comet, about 3 miles wide, may have exploded over southern Canada, nearly wiping out an ancient Stone Age culture as well as megafauna like mastodons and mammoths.

Source: wikipedia.org


Tuesday, May 23, 2017

Mounted skeleton cast of M. hoffmannii, Maastricht Natural History Museum

Mosasaurus (“lizard of the Meuse River”) is a genus of mosasaurs, carnivorous aquatic lizards. It existed during the Maastrichtian age of the late Cretaceous period, between about 70 and 66 million years ago, in western Europe and North America. The name means “Meuse lizard”, as the first specimen was found near the Meuse River (Latin Mosa + Greek sauroslizard).

Skeleton of M. beaugei by Ghedoghedo. Fossil – Took the picture at Musee des Confluences, Lyon

Mosasaurus was among the last of the mosasaurids, and among the largest. As with most mosasaurids, the legs and feet of Mosasaurus were modified into flippers, and the front flippers were larger than the hind flippers. The largest known species, M. hoffmannii reached lengths up to 17 m (56 ft), slightly longer than its relatives Tylosaurus and HainosaurusMosasauruswas also more robust than related mosasaurids. The skull was more robust than in other mosasaurids, and the lower jaws (mandibles) attached very tightly to the skull. They had deep, barrel-shaped bodies, and with their fairly large eyes, poor binocular vision, and poorly developed olfactory bulbs, experts believe that Mosasaurus lived near the ocean surface, where they preyed on fish, turtles, ammonites, smaller mosasaurs, birds, pterosaurs, and plesiosaurs. Although they were able to dive, they evidently did not venture into deeper waters.

The skull of Mosasaurus tapered off into a short, conical tip. The jaws were armed with massive conical teeth. Their paddle-like limbs had five digits in front and four in back. The body ended in a strong tail, which other mosasaurid fossils suggest had a fluke similar to those of sharks and some ichthyosaurs. The body probably remained stiff to reduce drag through the water, while the end of the tail provided strong propulsion.

Mosasaurus was the first genus of mosasaurs to be named. The first remains known to science were a fragmentary skull from a chalk quarry in the St Pietersberg, a hill near Maastricht, the Netherlands, found in 1764 and collected by lieutenant Jean Baptiste Drouin in 1766. It was procured for the Teylers Museum at Haarlem in 1784 by Martinus van Marum, the first director of the museum, who published its description only in 1790. He considered it to be a species of “big breathing fish” (Pisces cetacei, in other words: a whale). It is still part of the collection as TM 7424.

Mosasaurus hoffmani, Late cretaceous of Europe. Artwork by Nobu Tamura

The family Mosasauridae is split into several subfamilies, with Mosasaurus being placed within Mosasaurinae. This subfamily, in turn, is further split into smaller tribes, with Mosasaurus being grouped with ClidastesMoanasaurus, and Liodon in the tribe Mosasaurini.

Since the genus was first named in the early 19th century, numerous species have been assigned to Mosasaurus, both from North America and Europe. Many researchers have suggested that certain European species are actually synonyms of their American counterparts, though because many of the specimens involved are incomplete, scientists have gone back and forth regarding which species are synonyms and which are not. For example, the giant American species M. maximus is regarded by most researchers as a junior synonym of the European M. hoffmannii, though a few scientists maintain that the two can be distinguished by features of their skull bones.

Five species are generally recognized as valid today: M. hoffmannii Mantell, 1829 (the type species), M. conodon Cope, 1881,M. lemonnieri Dollo, 1889, M. beaugei Arambourg, 1952, and M. missouriensis (Harlan, 1834).

Source: Wiki.org, NatGeo.com

12 Terrifying Prehistoric Monsters

Sunday, May 7, 2017


Who hasn’t heard of a Tyrannosaurus rex or a velociraptor thanks to movies like Jurassic Park? When we think of dinosaurs, we almost all think of a very small subset of these giant creatures from history. But perhaps more interesting are those which are far less familiar to us all. This list is just a small selection of monstrous or weird-looking creatures from ancient times, most of which are little known to the public.

12 – Estemmenosuchus

Estemmenosuchus uralensis by Dinoraul

They don’t make animals like this anymore. Estemmenosuchus is one of the most bizarre-looking prehistoric monsters; it belonged to the group of the dinocephalians, and despite their dinosaur-like appearance, they were actually more closely related to mammals… including us! Estemmenosuchus was the size of a rhinoceros, and it too had a horn on its nose, but it also had antler-like horns on the top of its head, and strange, bony protrusions coming out of its cheeks; no one knows what they were used for. It also had a set of monstrous, sharp teeth, but scientists aren’t sure about its food preferences. Personally, I believe this thing was big and scary enough to eat anything it wanted. Fossil remains of Estemmenosuchus have been found in Russia; it lived in the Permian period, long before the appearance of dinosaurs.

11 – Acrophyseter

Acrophyseter deinodon by Bran Artworks

This was an ancient relative of today’s sperm whale, which as we all know (or should know) is huge, eats lots of squid and has never been known to attack humans without provocation. Acrophyseter was the complete opposite; it was moderately sized, and didn’t feed on squid but rather on other marine mammals and even on sharks! Its horrible-looking teeth were deadly weapons and have given Acrophyseter and its ancient relatives the nickname of “killer sperm whales”. Acrophyseter’s fossil remains have been found in Peru; it lived in the Miocene period, which seems to have been the best epoch for scary marine monsters including giant dolphins, colossal sharks and even monster penguins and seals.

10 – Epicyon

Epicyon vs Canis lupus by Mauricio Anton

Epicyon could well be described as a giant pitbull on steroids. It was a member of the Canidae or dog family, but whereas modern day canids are built for speed and endurance, Epicyon was built for brute strength, and had jaws so powerful that they could crush bone as if they were crackers! This beast ruled the plains of North America for fifteen million years, before it was replaced by big cats (including sabertooths).

9 – Edestus

Edestus by Prehistoric Wildlife

Today’s great white shark probably has some of the most nightmarish set of teeth in Nature, but its distant prehistoric relative Edestus was so scary that it would make the great white look almost cute. Edestus was about seven meters long and was one of the top predators of the Carboniferous seas. However, scientists still don’t know how it used its extraordinary teeth; instead of constantly losing the worn out teeth and replacing them with the new ones growing in rows behind, as modern day sharks do, Edestus didn’t lose its teeth at all; instead, the new teeth pushed the old teeth out of the mouth and, eventually, the gums and teeth would protrude out of the mouth like a pair of monstrous scissors. Regardless of how it did it, it seems obvious that Edestus could possibly cut any other creature in two with ease. But we still have trouble to imagine how a very old Edestus would “function”, or even how would it look!

8 – Gorgonopsid

Two dinogorgons — described as reptile-like mammals — squabble over a meal. By atrox1

This creature has earned some popularity recently thanks to the British sci fi show “Primeval”, where it was the very first monster to appear. Although real life gorgonopsids where a tad smaller than the TV version (the largest species, such as Inostrancevia and Leontocephalus, could grow up to six meters long), they were just as terrifying; as a matter of fact, they were the dominant predators during the late Permian, before dinosaurs and their relatives took over. Gorgonopsids had a set of deadly saber-teeth (some species had two sets of them) which came handy when hunting some of the largest Permian herbivores, often the size of rhinos or bigger.
They were quite agile and could probably run quite fast, unlike the predators that came before them. Despite their reptilian appearance, gorgonopsids were actually closely related to mammals, and it is even possible that they were covered in fur!

7 – Terror birds

Two big South American Terror Birds (Phorusrhacidae) by Roberto Díaz Sibaja

Terror birds, formally known as Phorusrhacids, were the top predators in South America and parts of North America during the Miocene, Pliocene and Early Pleistocene periods, before they were replaced by big cats and other carnivorous mammals. They were unable to fly, but could run very fast (as fast as a cheetah, according to some scientists!) and were very large; the largest species could grow up to three meters tall and weigh up to half a ton. Their main weapon was their head, which could be up to one meter long, allowing them to swallow prey as large as a dog in one single gulp! However, thanks to the hooked tip of the bill, similar to that of eagles and hawks, the terrors birds could kill and devour prey much larger than a dog, including horses, camels, etc.

6 – Madtsoia

Madtsoia by James Gurney

Madtsoia would be the worst nightmare of anyone with a phobia of snakes. Although only fragmentary remains are known, it is claimed to have reached the immense length of 15-20 meters! This creature appeared in the Cretaceous period and possibly dined on dinosaurs. It was similar to today’s boas and pythons in that it was not venomous, but rather squeezed its victims to death using its immense muscular strength. Madtsoia was such a successful predator, that it managed to survive the extinction that wiped out dinosaurs and other animals, but it finally went extinct about 45 million years ago. Other giant snakes are known to have existed, including one that was said to reach 29 meters in length.

5 – Purussaurus

Tick Tock by randomdinos

Purussaurus was a gigantic caiman (a relative to alligators) that lived in what is today known as the Amazonian rainforest. Back in Purussaurus’ days, 8 million years ago, that region was actually a vast inland sea teaming with crocodiles, gharials, fresh water whales, giant rodents and enormous turtles. Purussaurus was the top predator in that sea, and with good reason; at 12-15 meters long, maybe more, it was one of the largest crocodilians ever to have existed. The remains of other animals missing limbs or bitten in half are a macabre proof of this giant caiman’s appetite.

4 – Entelodon

Entelodons intimidating Hyaenodon by Petr Modlitba

Although pigs, wild boars and warthogs today are known to eat meat on occasion, they are basically vegetarian. On the other hand, the Entelodon, a prehistoric pig relative, was a full time carnivore and possibly one of the most monstrous-looking mammals ever. Standing on all fours, this beast was as tall as a man, and had an immense head armed with powerful jaws and sharp teeth. Scientists believe that it was able to hunt live prey, but that it also scared other predators away from their kills (which should have been very easy). Its bite marks also suggest that it fought viciously with its own kind, and it is even possible that Entelodonts were cannibalistic. Entelodons were quite successful beasts, existing for about 9 million years.

3 – Pulmonoscorpius

Pulmonoscorpius by Prehistoric Wildlife

This is by far the smallest creature of the list, but it would still cause hysteria, and perhaps even some heart attacks, if it showed up today. It was very similar to today’s scorpions but could grow up to one meter long, perhaps more, and was armed with sharp chelae (claws) and a venomous stinger. Of course, we don’t know how toxic its venom was, but considering the considerable amount it injected with each attack, it was most likely a very deadly critter indeed. A predator, Pulmonoscorpius roamed the swampy forests of the Carboniferous in what is today Scotland. Just so you know, during the Carboniferous there were also giant roaches the size of house cats, dragonflies the size of hawks, and centipede-relatives up to three meters long. No kidding.

2 – Xenosmilus

Pleistocene big cats of North America comparison by Prehistoric Wildlife 1 – Smilodon (large), 2 – Miracinonyx (American cheetah), 3 – Xenosmilus, 4 – Panthera leo atrox (American lion), 5 – Homotherium.

Since the formidable Smilodon (better known as saber-toothed tiger) is too well known, we have decided to go for a refreshing change. Enter Xenosmilus, possibly the nastiest feline ever to have existed. The remains of this very large cat (the size of a lion or tiger, but more robust) were recently found in Florida along with the remains of many unlucky giant peccaries (similar to wild pigs) that fell prey to it. Instead of strangling prey or breaking their neck as lions do, or stabbing them as the sabertoothed tiger did, Xenosmilus acted more like a shark or a carnivorous dinosaur, biting off a huge chunk of flesh and causing massive blood loss and shock in a matter of seconds. Compared to modern day felids, a Xenosmilus’ kill would probably be extremely bloody; so much in fact that it would probably not be shown in Animal Planet! Since we don’t know when exactly Xenosmilus became extinct, we can’t tell if humans ever met this cat, or fell prey to it.

1 – Megalodon 

Carcharocles Megalodon by SameerPrehistorica

This is a fairly well known prehistoric monster, but it is just so big and scary that it deserves to be in this list. Megalodon (technically called a Carcharocles megalodon) was a gigantic shark, closely related to today’s makos and great whites. It could grow up to 20 meters long and weigh up to 60 tons, being almost two times larger than Tyrannosaurus rex! Obviously, the only thing in the sea big enough to feed Megalodon where whales, and indeed, the giant shark’s bite marks have been found in the fossil remains of whales all around the world. Although many people like to imagine encounters between Megalodon and T-Rex, or dinosaur-like marine reptiles, the truth is Megalodon appeared long after the extinction of such creatures, and it wasn’t seen alive by any humans either, although it was still roaming the oceans when our australopithecine relatives took their first steps out of the jungle.

Source: listverse.com

Prehistoric Creatures Worse Than Your Nightmares

Thursday, April 6, 2017


Prehistory had no shortage of terrifying monsters, with everything from the more well-known Raptors and Rexes to super rats and three-eyed shrimp.

A Carnivorous Monster With a 40-Foot Wingspan.

The concept of a flying, carnivorous lizard is plenty terrifying on its own. Even in movies, pterodactyls and such are pretty small, because you simply don’t need to up the fear quotient by depicting the things as 40 feet across or like 400 pounds. But that didn’t stop nature from being the unholy little achiever that it is and doing just that.

The Azhdarchidae family were a group of gigantic pterosaurs that plied the skies of the late Cretaceous. Members of the group included Quetzalcoatlus (named after the Aztec sun god Quetzalcoatl, a giant feathered serpent), Azhdarcho (named after a type of Uzbek dragon) and Titanopteryx (whose name means “really big opteryx”). Now, let’s not get carried away and start picturing leathery-winged reptilian bird-things hunting you down from the skies and carrying you off to feed their younglings. Evidence shows that they were simply too large to have effectively grabbed prey and flown off with it.

Oh, is that not comforting? That the bird monster’s only problem was being too fucking gargantuan to fly away with your corpse after it killed you? Sorry. Does this scale diagram help?

The Azhdarchidae didn’t fly away with its prey like modern-day hawks, but only because that’s nowhere near terrifying enough. No, the Azhdarchidae would spot you from the air, slam down into the ground next to you and creepily hobble-wing-charge your ass, scooping you up into its huge, jagged beak. We’re not exaggerating that disturbing, high-speed death-waddle — scientists believe that Azhdarchidae had a “particularly efficient terrestrial locomotion,” which they were able to discern from preserved tracks that showed it placing its feet in front of its wing-claws as it moved.

The T. rex … Dog?

No, that’s not real, is it? That looks like the end boss of a Resident Evil game. It looks like one of the slags from Borderlands. It looks like the terrifying gritty reboot of Dino for the new Flintstones movie.

Sadly, that beast is not the fever dream of a horror game designer, but rather a real, once-living predator called a gorgonopsid, which was essentially a bear-sized saber-toothed dog-lizard with a 3-foot-long skull. Gorgonopsids of the genus Inostrancevia were even larger — about the size of a rhino — with canines roughly 4 inches long. Gorgonopsids were the dominant predator on land for the bulk of the Permian period, only being wiped out by the Permian-Triassic extinction event, which rebooted 90 percent of all life on Earth.

The Giant Alligator-Shark That Ate Sea Monsters

The Cretaceous period was basically the Earth’s goth phase, when all it cared about was finding something evil and monstrous enough to freak out its conservative parents. And it finally found that in the Hainosaurus and Tylosaurus, two types of prehistoric sea lizard that mama sharks used to scare their little shark babies into finishing their mackerel. Oh, and hey: You don’t need to imagine what those freaky shark nightmares looked like; National Geographic has done that for you.

But don’t worry; it’s not what it looks like. Tylosaurus didn’t really use that row of vicious teeth, nor even the two additional rows behind it. They were just there to make sure anything it swallowed whole didn’t wriggle free.

Oh, right: They swallowed sharks whole.

They mostly only used those three rows of giant razor-sharp fangs as a barb-wire fence to keep their prey from escaping being digested alive. It was like a sarlacc the size of a school bus, except this one could actually chase you down and force you into its belly.

They ate literally anything they could catch, including plesiosaurs, which is basically the Loch Ness Monster. Isn’t that comforting? Even monsters have monsters they’re scared of.

The Terrible Pigs

Funny. Who slipped concept art from the first Ghostbusters into our article research?

Wait, what? That’s not Zuul? That’s Daeodon, the granddaddy of modern pigs? That’s what bacon used to look like?!

Daeodon was about the size of a rhino, and while modern boars are just angry pigs with fur, this thing was also equal parts Cape buffalo and leopard.

The name literally means “hostile destructive teeth,” but the creature was for a time known simply as Dinohyus, or “terrible pig.” They were “massive opportunistic omnivores,” meaning that they pretty much ate whatever they could get their considerable jaws around. Which, uh … would be most things, by the look of it. Here, have a screenshot from the BBC’s Walking With Beasts.

The Sea Monsters That Ate the Other Sea Monsters That Ate Sea Monsters

If there is one thing you take away from your time on Cracked, let it be this: No matter how terrified you are of the sea, you aren’t terrified enough. Kronosaurus and Liopleurodon embody everything that could possibly be frightening about the ocean (well, except for maybe tentacles, but that’s likely only because they thought tentacles were delicious).

Liopleurodon looked like a rough draft of a crocodile rejected by God with a note to “Tone it way, way down, man.” It regularly reached 33 feet long, with one specimen discovered that had a jawbone 10 feet long. Given the proportions of some of the more complete remains found, some scientists speculate that Liopleurodon actually grew up to 50 feet long. Much like the Tylosaurus, the only prey big enough to quell the mighty hunger of Liopleurodon was other crazy, huge monsters, seen here in BBC’s insane artistic rendering:

Liopleurodon reconstructed by the BBC. “Walking With Dinosaurs”. © BBC 2000

Speaking of the living avatars of fear on Earth, let’s talk about the Kronosaurus, which was likely even bigger than Liopleurodon. Kronosaurus was named after the Titan Kronos, who was such a grand, evil bastard that he ate his own children (who were already pretty giant and terrifying themselves).

Kronosaurs had large “banana-shaped” teeth and thick jaws designed to crush the shells of ammonites, which were ancient shelled squids from back before nature decided that armoring the Kraken was “perhaps a bit overkill.”

 T. rex: The Xtreme Editions

Coming face-to-face with a T. rex would be a bad day for anyone. The only thing worse would be somehow surviving that encounter only to find out he’s got a pissed-off big brother waiting around the corner. But don’t freak out, the T. rex doesn’t have a more terrifying rivalry.

It has two: Giganotosaurus and Carcharodontosaurus.

Carcharodontosaurus skull cast, Science Museum of Minnesota. Photo by Matthew Deery

Both lived about 100 million years ago, were roughly 45 feet long and made the T. rex look like the neurotic, asthmatic nerd of the Rex family. The Carcharodontosaurus is pictured above, and is considered to be the second largest land predator in history (that’s called foreshadowing, friends). While Gigonotosaurus lived in South America and looked like this:

Giganotosaurus carolinii by durbed

2 – The Gargantuan Buck-Toothed Fang Fish

There’s a unique subgenre of terror that’s actually augmented by a bit of goofiness. It’s like spotting a clown holding a carving knife: Somehow the big floppy shoes make him so much worse than a normal knife-wielding maniac. So it is with the Dunkleosteus, a 30-foot murder-fish bred with a tank and armed with giant, buck-toothed blades all up in its face.

We’re not embellishing a harmless thing because it looks scary: The Dunkleosteus is estimated to have possessed the strongest bite out of anything. Ever. For some perspective, one of the strongest bites on Earth today comes from the hyena, at 2,000 Newtons (about 500 pounds of force). They easily crack bones with their mouths. The T. rex is estimated to have had a bite around 13,000 Newtons (3,000 pounds of force), which, once you realize bones crack at 1/6 that force, just seems like spite.

The Dunkleosteus had around 150 million Pascals of bite force, roughly 22,000 pounds of force per square inch. That is so powerful they changed units of measurement just to calculate it. If you came across a Dunkleosteus while exploring the ocean in the world’s most well-armored time-traveling submarine, Dunkleosteus would not only still eat you, but complain that, if anything, you were a bit soggy.

Dunkleosteus could also open its mouth in a 50th of a second, meaning that it vacuumed in animals that would normally be fast enough to swim away from it. Usually, fish either have a fast bite or a powerful one, because you can get plenty of food with only one of the two. But Dunkleosteus had both, because evolution is a spiteful bitch that hates life like they used to date and life banged its sister the night before the wedding.

The Largest Land Predator Ever

Hey, remember that foreshadowing from earlier? Here’s the thing casting that unusually large, spiky, quickly approaching shadow.

That’s a Spinosaurus, and it grew up to 60 feet long. Its “crocodile-like” jaws easily reached 5 feet in length alone, and it sported a jaunty sail on its back, because who was going to say anything about it?

Spinosaurus, an important dinosaur of Africa. Photo Credit: Wikimedia Commons

Believed to be the largest predator ever to walk the Earth, Spinosaurus is, at least for now, the King Scary Bastard in an entire epoch of the scariest bastards in history. Here’s the mouth of one of Spinosaurus’ smaller, gentler cousins, Suchomimus:

"Dino Suchomimus Eating Crowd", photo by Mike Hettwer

Jesus, is that a skull or industrial logging equipment? That’s it: We’re starting a collection to distribute cyanide pills to toddlers, females and Internet comedians. Because if Jurassic Park ever comes to life and gets a hold of any of these things, humanity’s best option is to just get the hell out of this whole “nature” thing altogether, and brother, we’re calling it now — it is women, children and Cracked writers first.

Source: cracked.com


Monday, May 1, 2017

Daeodon by Pablo Lara

Daeodon (from Greek, δαίος, daios “hostile” or “dreadful”, and οδον, odon “teeth”) is a genus of entelodont artiodactyl that inhabited North America between 29 and 19 million years ago during the late Oligocene and early Miocene epochs. The type species is Daeodon shoshonensis, the last and largest of the entelodonts; known adults of this species possessed skulls about 90 cm (3 ft) in length. It had a broad distribution across the United States, but it was never abundant.

Daeodon by Prehistoric Wildlife

Although not specified in Cope’s original description, the name Daeodon comes from the Greek words daios, meaning “hostile” or “dreadful” and odon, meaning “teeth”.

The genus Daeodon was erected by the American anatomist and paleontologist Edward Drinker Cope in 1878. He classified it as a perissodactyl and thought that it was closely related to “Menodus”. This classification persisted until the description of “Elotherium” calkinsi in 1905, a very similar and much more complete animal from the same rocks, which was promptly assigned as a species of Daeodon by Peterson (1909). This led to Daeodon’s reclassification as a member of the family Entelodontidae. The exact relationships between Daeodon and other entelodonts are not well understood, some authors (Lucas et al., 1998) consider the greater morphological similarity of Daeodon to Paraentelodon rather than to earlier North American entelodonts, like Archaeotherium, as evidence for Daeodon being a descendent from a Late Oligocene immigration of large Asian entelodonts to North America. However, the existence of distinct specimens of Archoetherium showing characters reminiscent of those present in both Paraentelodon and Daeodon raises the possibility of both genera actually descending from a North American common ancestor.

Entelodons intimidating Hyaenodon by Petr Modlitba

The type species of Daeodon is D. shohonensis, which is based on a fragment of a lower jaw from the John Day Formation of Oregon. Several other species were assigned to the genus in the subsequent decades, like D. calkinsiD. mento and D. minor. Since 1945, it had been suggested that two other taxa were actually junior synonyms of Daeodon, but the formalization of this referral didn’t take place until the work of Lucas et al. (1998). Ammodon leidyanum, named by Cope’s rival, O. C. Marsh, and Dinohyus hollandi, a complete skeleton from the Agate Springs quarry of Nebraska, were found to be indistinguishable from each other and in turn both were indistinguishable from D. shoshonensis. With the exception of D. calkinsi, which was tentatively excluded from Daeodon, the other previously recognized species of Daeodon were also synonymized to D. shoshonensis. That same year, an obscure entelodont, Boochoerus humerosum, was also synonymized to Daeodon by Foss and Fremd (1998) and, albeit its status as a distinct species was retained, they note that the differences could still be attributed to individual or population variation or sexual dimorphism.

Daeodon shoshonensis is the largest known entelodont; known adult individuals had skulls about 90 cm (3 ft) long and were around 1.8 m (5.9 ft) tall at the shoulders. It’s differentiated from other entelodonts by a suite of unique dental characters, the shape and relatively small size of the cheekbone flanges of its skull compared to those of Archaeotherium, the small size of its chin tubercle, as well as features of its carpus and tarsus and the fusion of the bones of the lower leg. Like other entelodonts, its limbs were long and slender with the bones of the foreleg fused together and with only two toes on each foot. It also had a relatively lightly constructed neck for the size of its head, whose weight was mostly supported by muscles and tendons attached to the tall spines of the thoracic vertebrae, similar to those of modern-day bison and white rhinoceros.

A skull of Daeodon shoshonensis at the Carnegie Museum of Natural History. Author: Matt Celeskey

10 Facts About Sarcosuchus

Monday, April 24, 2017

10 Facts About Sarcosuchus

Meet Sarcosuchus, the 10-Ton Prehistoric Crocodile

Sarcosuchus (meaning “flesh crocodile”) is a genus of crocodyliform and distant relative of living crocodylians that lived 112 million years ago. It dates from the early Cretaceous Period of what is now Africa and South America and is one of the largest crocodile-like reptiles that ever lived. It was almost twice as long as the modern saltwater crocodile and weighed up to 8 tonnes.

Sarcosuchus – SuperCroc

Sarcosuchus Is Also Known as the SuperCroc

Sarcosuchus vs Carcharodontosaurus

The name Sarcosuchus is Greek for “flesh crocodile,” but that apparently wasn’t impressive enough for the producers at National Geographic. In 2001, this cable channel bestowed the title “SuperCroc” on its hour-long documentary about Sarcosuchus, a name that has since stuck in the popular imagination. (By the way, there are other “-crocs” in the prehistoric bestiary, none of which are quite as popular as SuperCroc: for example, have you ever heard of the BoarCroc or the DuckCroc?)

Sarcosuchus Kept Growing Throughout its Life Span

Sarcosuchus by Sameer Prehistorica

Unlike modern crocodiles, which attain their full adult size in about ten years, Sarcosuchus seems to hve kept growing and growing at a steady rate throughout its lifetime (paleontologists can determine this by examining bone cross-sections from various fossilized specimens). As a result, the largest, most superannuated SuperCrocs reached lengths of up to 40 feet from head to tail, compared to about 25 feet max for the biggest croc alive today, the Saltwater Crocodile.

Sarcosuchus Adults May Have Weighed More than 10 Tons

Wikimedia Commons

What made Sarcosuchus truly impressive was its dinosaur-worthy weight: more than ten tons for those 40-foot-long senior citizens described in the previous slide, and perhaps seven or eight tons for the average adult. If the SuperCroc had lived after the dinosaurs had gone extinct, rather than right alongside them during the middle Cretaceous period (about 100 million years ago), it would have counted as one of the largest land-dwelling animals on the face of the earth!

Sarcosuchus May Have Tangled With Spinosaurus

Sarcosuchus vs Spinosaurus by sameerprehistorica

Although it’s unlikely that Sarcosuchus deliberately hunted dinosaurs for lunch, there’s no reason it had to tolerate other predators that competed with it for limited food resources. A full-grown SuperCroc would have been more than capable of breaking the neck of a large theropod, such as, say, the contemporary, fish-eating Spinosaurus, the largest meat-eating dinosaur that ever lived.

The Eyes of Sarcosuchus Rolled Up and Down, not Left and Right

Sarcosuchus by Nobu Tamura

You can tell a lot about an animal”s accustomed behavior by observing the shape, structure, and placement of its eyes. The eyes of Sarcosuchus didn’t move left and right, like those of a cow or panther, but rather up and down, indicating that the SuperCroc spent much of its time submerged partway below the surface of freshwater rivers (like modern crocodiles), scanning the banks for interlopers and occasionally breaching the surface to snap at encroaching dinosaurs and drag them into the water.

Sarcosuchus Lived in What (Today) Is the Sahara Desert

The SuperCroc fossils were found in sub-Saharan Africa, in what is now Niger. The map above shows the Earth as it may have looked about 110 million years ago, when Sarcosuchus imperator lived. Map by Ron Blakey

One hundred million years ago, northern Africa was a lush, tropical region crisscrossed by numerous rivers; it has only been relatively recently (geologically speaking) that this area dried out and became overspread by the Sahara, the largest desert in the world. Sarcosuchus was only one of a wide variety of plus-sized reptiles that took advantage of this region’s natural abundance during the later Mesozoic Era, basking in its year-round heat and humidity; there were also plenty of dinosaurs to keep this croc company!

The Snout of Sarcosuchus Ended in a “Bulla”

Wikimedia Commons

The bulbous depression, or “bulla,” at the end of Sarcosuchus’ long, narrow snout continues to be a mystery to paleontologists. This may have been a sexually selected characteristic (that is, males with larger bullas were more attractive to females during mating season, and thus managed to perpetuate the trait), an enhanced olfactory (smelling) organ, a blunt weapon deployed in intra-species combat, or even a sounding chamber that allowed Sarcosuchus individuals to communicate with each other over long distances.

Sarcosuchus Mostly Subsisted on Fish

Sarcosuchus by Renata Cunha

You’d think a crocodile as big and heavy as Sarcosuchus would have feasted exclusively on the plus-sized dinosaurs of its habitat–say, half-ton hadrosaurs that wandered too close to the river for a drink. Judging by the length and shape of its snout, though, it’s likely that the SuperCroc ate fish pretty much exclusively (gigantic theropods equipped with similar snouts, like Spinosaurus, also enjoyed piscivorous diets), only feasting on dinosaurs when the opportunity was too good to pass up.

Sarcosuchus Was Technically a “Pholidosaur”

A typical pholidosaur (Nobu Tamura).

Its catchy nickname aside, the SuperCroc wasn’t a direct descendant of modern crocodiles, but rather an obscure type of prehistoric reptile known as a “pholidosaur.” (By contrast, the almost-as-big Deinosuchus was a genuine member of the crocodile family, though it has technically been classified as an alligator!) The crocodile-like pholidosaurs went extinct millions of years ago, for reasons that are still uncertain, and haven’t left any direct living descendants.

Sarcosuchus Was Covered Head to Tail in Osteoderms

Wikimedia Commons

The osteoderms, or armored plates, of modern crocodiles aren’t continuous–you can detect a break (if you dare to venture close enough) between their necks and the rest of their bodies. Not so with Sarcosuchus, the entire body of which was covered with these plates, except for the end of its tail and the front of its head. Tellingly, this arrangement is similar to that of another crocodile-like pholidosaur of the middle Cretaceous period, Araripesuchus, and may have had a deleterious effect on Sarcosuchus’ overall flexibility.

Source: thoughtco.com