THe Sherassic Park - A PaLeontologic adventure

[LeonardoBjj]

I like to think there's a gigantic T-Rex waiting to be discovered by science.

- There's probably bigger T-rex. I will post about the 3 sugested divisions on the Rexes family when i get on a pc.

 

[Zookeeper Gabe]

I very much look forward to this thread and where it goes

 

[MLarson]

I very much look forward to this thread and where it goes

Any prehistoric animals you'd like see in a zoo?

 

[Zookeeper Gabe]

Any prehistoric animals you'd like see in a zoo?

I feel like there have been a few movies about why that’s a bad idea…




Jkjk
Literally any of them, so many cool animals even the non dinosaurs. Some really cool extinct crocodiles, weird mammals, giant inverts, insane fish.

 

[LeonardoBjj]

- Look like the theory didn't last vary long:

CNN — A provocative study published earlier this year proposed that the world’s best-known and perhaps best-loved dinosaur, Tyrannosaurus rex, was actually three separate species.

Not so fast, says new research published Monday, which argues that T. rex shouldn’t be reclassified. Any variations in fossils merely reflect the fact that dinosaurs, like humans, come in different shapes and sizes.

“Tyrannosaurus rex remains the one true king of the dinosaurs,” said paleontologist Steve Brusatte, study coauthor of the latest analysis and professor at The University of Edinburgh’s School of Geosciences in Scotland, in a news release.

“It is true that the fossils we have are somewhat variable in size and shape, but as we show in our new study, that variation is minor and cannot be used to neatly separate the fossils into easily defined clusters. Based on all the fossil evidence we currently have, T. rex stands alone as the single giant apex predator from the end of the Age of Dinosaurs in North America.”

The earlier controversial paper, which was published in March, had analyzed the bones and teeth of 37 T. rex specimens. This research suggested that T. rex should have two sibling species – a more slender Tyrannosaurus regina (tyrant lizard queen) and the stouter and toothier Tyrannosaurus imperator (tyrant lizard emperor).

Full read at: https://edition.cnn.com/2022/07/25/world/t-rex-true-king-of-dinosaurs-scn/index.html

The controversial study:
Tyrannosaurus rex is the most iconic dinosaur. Its skeletons hold pride of place in museums around the world, and sell for millions of dollars at auction — and a bounty of relatively complete specimens have made it the most thoroughly studied dinosaur in the world.

But in a new paper published Tuesday in Evolutionary Biology, three researchers argue that the animal we currently call Tyrannosaurus rex should actually be split into three separate species, with T. rex being joined by two cousins they name Tyrannosaurus imperator, or the emperor, and Tyrannosaurus regina, the queen.

“This paper is likely to rock the paleo community, and the public that is so used to good old T. rex,” said Gregory Paul, an independent paleontologist and paleoartist and author on the paper.

Tyrannosaur experts largely disagree. Thomas Carr, a paleontologist at Carthage College in Kenosha, Wis., calls the evidence for multiple species “vanishingly weak.” Another paleontologist removed himself as an author of the paper before it moved to publication. And curators at museums with Tyrannosaurus specimens that would be affected by these reclassifications say they aren’t going to rename anything based on the proposal.

https://www.nytimes.com/2022/02/28/science/tyrannosaurus-rex-species.html

- But i've read theorys that since dinosaurs lived ona world of inimaginable violence(Who wrote that didn't looked around at mankind), theres probably they didn't get grown to very old age, so very few got to supass the avarage size. Just like crocodilians in the wild today. The same aplies to the other dinosaurs.

 

[MLarson]

I feel like there have been a few movies about why that’s a bad idea…




Jkjk
Literally any of them, so many cool animals even the non dinosaurs. Some really cool extinct crocodiles, weird mammals, giant inverts, insane fish.

The pic of the Fossa that I posted in In your zoo thread also had a giant ancestor.

I'm trying to find a size comparison of it to post.

 

[LeonardoBjj]

I feel like there have been a few movies about why that’s a bad idea…




Jkjk
Literally any of them, so many cool animals even the non dinosaurs. Some really cool extinct crocodiles, weird mammals, giant inverts, insane fish.

- What your opinion on animals extinct by humans stupidy? If we could bring back the Barbary lion?

 

[MLarson]

 

[Zookeeper Gabe]

- What your opinion on animals extinct by humans stupidy? f we could bring back the Barbary lion?

That’s a tough question, my immediate answer is yes. But there are so many variables, we are running out of wild places for the animals we have now. So to bring an animal back from extinction there would need to be a lot of factors in play.

 

[Tyrannosaurus rex]

- I've got something bigger here:

Carcharodontosaurus, the "Great White Shark" Dinosaur
By
Bob Strauss
Updated on February 07, 2019
Carcharodontosaurus, the "Great White Shark lizard," certainly has a fearsome name, but that doesn't mean it springs as readily to mind as other plus-sized meat-eaters like Tyrannosaurus Rex and Giganotosaurus. On the following slides, you'll discover fascinating facts about this little-known Cretaceous carnivore. fascinating facts about this little-known Cretaceous carnivore.

Around 1930, the famous German paleontologist Ernst Stromer von Reichenbach discovered the partial skeleton of a meat-eating dinosaur in Egypt―on which he bestowed the name Carcharodontosaurus, "Great White Shark lizard," after its long, shark-like teeth. However, von Reichenbach couldn't claim Carcharodontosaurus as "his" dinosaur, since virtually identical teeth had been discovered a dozen or so years before.

Because of its limited fossil remains, Carcharodontosaurus is one of those dinosaurs whose length and weight is especially difficult to estimate. A generation ago, paleontologists flirted with the idea that this theropod was as big, or bigger than, Tyrannosaurus Rex, measuring up to 40 feet from head to tail and weighing as much as 10 tons. Today, more modest estimates put the "Great White Shark lizard" at 30 or so feet long and five tons, a couple of tons less than the biggest T. Rex specimens.

https://www.thoughtco.com/things-to-know-carcharodontosaurus-1093777

Carcharodontosaurus saharicus
This huge meat eater was 45 feet long (5 feet longer than T-rex) and weighed 8 tons, making it one of the largest carnivores that ever walked the earth. This African carnosaur had a gigantic 5’4" long skull and enormous jaws with 8" long serrated teeth. It walked on two legs, had a massive tail, bulky body and short arms ending in three-fingered hands with sharp claws. Carcharodontosaurus is one of the longest and heaviest known carnivorous dinosaurs, with various scientists proposing length estimates ranging between 12 and 13 m (39-43.5 ft) and weight estimates between 6 and 15 metric tons. Its long, muscular legs, and fossilized trackways indicate that it could run about 20 miles per hour, though there is some controversy as to whether it actually did, a forward fall would have been deadly to Carcharodontosaurus, due to the inability of its small arms to brace the animal when it landed. Carcharodontosaurus was a carnivore, with enormous jaws and long, serrated teeth up to eight inches long.

https://carnivora.net/carcharodontosaurus-saharicus-v-tyrannosaurus-rex-t117.html

8 Prehistoric Predators Bigger than T-Rex
Amphora17 Dec 2016Prehistoric Animals


T-Rex has held its title in the public eye as the biggest meat-eater for too long. Here come 8 prehistoric menaces which will make you wish you stuck with Rex.

1.Titanoboa. This was a monstrous snake that lived during the Palaeocene and grew up to 15 metres long. It lived in the relatively warm and forested epoch, which fuelled the growth of this massive predator. With teeth like modern python’s that curved backwards, Titanoboa would hold onto its prey with its curved teeth whilst crushing its body with its immense bulk.

2. Giganotosaurus. Growing over 13 metres long, this Cretaceous dinosaur lived in what would be modern-day South America. It made headlines over the world when it was discovered as a dinosaur that was bigger than T-Rex. It is thought to have hunted the giant South American titanosaurs, such as Argentinosaurus, by slicing through their flesh with its razor-sharp teeth and waiting for blood loss and infection to finish off the mammoth creature. Another species related to Giganotosaurus (also bigger than T-Rex) called Mapusaurus, was thought to have hunted in packs to bring down its titanosaur prey.

3. Mosasaurus. This is the first discovered of a Cretaceous group of marine reptiles, the mosasaurs, and this species grew up to 18 metres long. Although not as long as some other mosasaurs, it was very heavily built with powerful muscles and a killer bite. It didn’t have a very good sense of smell, so probably hung around near the surface, catching prey when it went to the surface to breathe – remember these are marine reptiles and have to breathe as much as any other reptile. It probably fed on marine reptiles, fish (including sharks), sea birds, pterosaurs and the occasional dinosaur.

4. C.megalodon.With larger estimates of size reaching 20 metres long, this shark was truly colossal, and died out fairly recently, in the Pleistocene (in fact, some people reckon it’s still around today!). C.megalodon is only known from its teeth and vertebra, as shark skeletons are made of cartilage, which doesn’t fossilise. In fact, c.megalodon teeth used to be thought to be the tips of dragon tongues, hence the many arrowhead tongued dragons of medieval folklore.It is thought to have hunted in the murky depths and attacked on small whales near the surface by swimming up really quickly and slamming into the whale from underneath, stunning it and causing immense damage to its body.

5. Carcharodontosaurus. Another dinosaur bigger than T-Rex, Carcharodontosaurus lived in Cretaceous Africa. Carcharodontosaurus comes from the Carcharodon genus of sharks that includes the great white shark. The name basically means ‘shark tooth reptile’, because of Carcharodontosaurus’ sharp shark-like teeth. Carcharodontosaurus has often been called the ‘African T-Rex’, which is false because it wasn’t a tyrannosaur, it was actually closer related to Giganotosaurus of South America.

6. Basilosaurus. The one mammal on this list, Basilosaurus was a giant meat-eating whale from the Eocene. Growing up to 18 metres long, this whale had a serpentine shape with massive powerful jaws. It evolved from early land mammals and hunted on early whales. Occasionally it ventured inland to snack on water-dwelling creatures of the shallow inland Eocene seas. One of the most confusing things about this animal is its name, which means ‘King Lizard’. This is because when out was discovered, it was thought to be a mosasaur. When realised to be a whale, it was renamed Zeuglodon (yoked tooth) but the name was shortly reversed to Basilosaurus

7. P.funkei a.k.a Predator X. This recently discovered Jurassic pliosaur grew to almost fifteen metres long. For a while, it was simply called Predator X, before the proper species name, P.funkei, was created. With jaws making up a large proportion of its body, this hunted on plesiosaurs, sharks and other marine reptiles. Large adults would even be able to take down giant fish like Leedsichthys. This monster ruled the Jurassic seas.

8. Spinosaurus. This Cretaceous Egyptian dinosaur is the largest meat-eating dinosaur of all time. Growing up to 18 metres long, it bested T-rex in a long way. It lived in the same African ecosystem as Carcharodontosaurus, but while the latter hunted on land, Spinosaurus is thought to be an aquatic predator, the first known dinosaur specialised for hunting in water. Since the 1990s Spinosaurus had been depicted as a bipedal (two-legged) predator but in 2014 more accurate research showed that it actually walked on four legs, a controversial discovery nearly all predatory dinosaurs before walked on two legs. Spinosaurus hunted large fish in rivers in Africa and was the biggest predatory dinosaur ever

https://tyrannosauruniversity.wordpress.com/2016/12/17/8-prehistoric-predators-bigger-than-t-rex/

To be fair, I think the size of some of the big theropods are exaggerated a bit. Especially Giganotosaurus, Carcharodontosaurus and Spinosaurus. Most of that is the result of early size estimates getting mentioned before the fossils are properly studied and the media just running with it. Giganotosaurus and Carcharodontosaurus were barely any longer or taller than T.rex, and they certainly weren't any heavier. They were far slimmer and less muscular than T.rex. Tyrannosaurus was a tank compared to those two. I think there's just kind of a "want" for something bigger and scarier than T.rex.

Spinosaurus is a bit of an odd one, paleontologists' interpretations change every few years when new material is discovered. The problem is the the remains are very fragmented and they're not sure if they belong to the same individual or even the same genus or species at all.

 

[LeonardoBjj]

That’s a tough question, my immediate answer is yes. But there are so many variables, we are running out of wild places for the animals we have now. So to bring an animal back from extinction there would need to be a lot of factors in play.

- The one that always come to my mind is the Tasmanian wolf. That footage of the poor creature in a jail just breaks my heart.

 

[LeonardoBjj]

To be fair, I think the size of some of the big theropods are exaggerated a bit. Especially Giganotosaurus, Carcharodontosaurus and Spinosaurus. Most of that is the result of early size estimates getting mentioned before the fossils are properly studied and the media just running with it. Giganotosaurus and Carcharodontosaurus were barely any longer or taller than T.rex, and they certainly weren't any heavier. They were far slimmer and less muscular than T.rex. Tyrannosaurus was a tank compared to those two. I think there's just kind of a "want" for something bigger and scarier than T.rex.

Spinosaurus is a bit of an odd one, paleontologists' interpretations change every few years when new material is discovered. The problem is the the remains are very fragmented and they're not sure if they belong to the same individual or even the same genus or species at all.

- I do agree with you. The spino is belivied to be longer. But lighter than the rex. The carchadonto and the giga is that some could match or surpass the rex. And some rexes could surpass those. Like some black caimans here in Brasil can match or surpass bigger crocodilians.

They found a new Carcharodontosaurus that is bellievied to pass the 10 ton mark.

C. saharicus (the type species) was the largest of the genus Carcharodontosaurus, with various sources suggesting length estimates ranging between 12 and 13 meters (39-43.5 ft), a height of 3.6 meters (12 ft) at the hip, and weight estimates between 6 and 15 metric tons. The restored skull of the neotype measures in at roughly 1.5 meters or about 4.9 feet. If these measurements are correct, then Carcharodontosaurus is one of the heaviest and longest of the known carnivores. Paleontologists believe that the massive size of Carcharodontosaurus is attributed to their need to outcompete other large carnivores and take down sauropods that reached lengths of 32 meters (108 feet).

With their massive physical size comes the need for a large feeding territory, estimated near 310 square miles per dinosaur. Because of this huge range, it is believed that Carcharodontosaurus was highly territorial, often skirmishing with other Carcharodontosaurus and other theropods, such as Bahariasaurus, and the giant crocodilian, Sarcosuchus, over food. A common trend found on large theropod skulls is to exhibit antemortem bite marks that suggest these carnivores were often involved in territorial battles over prey, mates, or scavenging rights.

https://www.fossilera.com/pages/about-carcharodontosaurus

- I would love if they found a bigger Stegosaurus or triceratops.

 

[Tyrannosaurus rex]

- I do agree with you. The spino is belivied to be longer. But lighter than the rex. The carchadonto and the giga is that some could match or surpass the rex. And some rexes could surpass those. Like some black caimans here in Brasil can match or surpass bigger crocodilians.

They found a new Carcharodontosaurus that is bellievied to pass the 10 ton mark.

C. saharicus (the type species) was the largest of the genus Carcharodontosaurus, with various sources suggesting length estimates ranging between 12 and 13 meters (39-43.5 ft), a height of 3.6 meters (12 ft) at the hip, and weight estimates between 6 and 15 metric tons. The restored skull of the neotype measures in at roughly 1.5 meters or about 4.9 feet. If these measurements are correct, then Carcharodontosaurus is one of the heaviest and longest of the known carnivores. Paleontologists believe that the massive size of Carcharodontosaurus is attributed to their need to outcompete other large carnivores and take down sauropods that reached lengths of 32 meters (108 feet).

With their massive physical size comes the need for a large feeding territory, estimated near 310 square miles per dinosaur. Because of this huge range, it is believed that Carcharodontosaurus was highly territorial, often skirmishing with other Carcharodontosaurus and other theropods, such as Bahariasaurus, and the giant crocodilian, Sarcosuchus, over food. A common trend found on large theropod skulls is to exhibit antemortem bite marks that suggest these carnivores were often involved in territorial battles over prey, mates, or scavenging rights.

https://www.fossilera.com/pages/about-carcharodontosaurus

- I would love if they found a bigger Stegosaurus or triceratops.

I'd be interested to read more about that particular Carcharodontosaurus. I always take these new claims with a big grain or salt until the material is properly studied and published.
That said, I wouldn't be surprised if there were some absolutely gigantic individuals in all of the big theropods. I just hope some get found lol. That said, I think there seems to be a soft upper limit of about rougly 12.5-13 meters for most theropods. That's roughly where all of the big ones seems to top out at, give or take a bit. Some individuals would undoubtedly have surpassed that, but probably not as a species. Barring Spinosaurus possibly since it has a completely different body plan.

 

[LeonardoBjj]

New Dinosaur Species Is Oldest Ever Found in Africa

A small, speedy, omnivorous dinosaur was a forerunner of Brachiosaurus and other giant plant-eaters
By Riley Black on August 31, 2022

Sauropods were dinosaurs that truly lived large. This group of long-necked, four-legged herbivores, such as the celebrated species Apatosaurus and Brachiosaurus, included the largest creatures to ever walk the planet. Some grew to more than 100 feet long and weighed more than 80 tons. Now paleontologists have uncovered one of the earliest members of this storied lineage of lumbering giants: a svelte, much smaller omnivore that once darted across the floodplains of prehistoric Zimbabwe.

The new dinosaur, described on Wednesday in Nature, is named Mbiresaurus raathi. The moniker references Mbire, the district of Zimbabwe where the fossil was found, and pays tribute to paleontologist Michael Raath, who first published on fossils from the area. The creature is the oldest dinosaur yet found in Africa, Yale University paleontologist Christopher Griffin and his colleagues report—and it represents the early days of a lineage that would come to include classic dinosaurs such as Diplodocus.

The dinosaur’s discovery came from an effort to understand how plants and animals were affected by climate change during the Triassic period, between 252 million and 201 million years ago. “Dinosaurs began to disperse across the globe during this time,” Griffin says, with the earliest dinosaur remains generally found at localities that would have been at the same latitude in Triassic South America and India. After Raath reported fossils of a similarly early age in Zimbabwe, paleontologists went looking for more—and got more than they anticipated. During one such expedition, Griffin recalls, he uncovered what turned out to be the left femur of a Mbiresaurus. “The femur is one of those distinctive bones that you can tell right away is from a dinosaur,” he says, “so once I dug that out, I knew I was holding the oldest definitive dinosaur ever found in Africa.”

The newly found specimen, which was surprisingly complete for a very early dinosaur, belonged to a group called sauropodomorphs. This roughly 230-million-year-old Mbiresaurus is represented by a nearly complete skeleton, containing parts of the skull and spinal column and elements of both the front and hind legs. “We’re really only missing parts of the hands, an ankle bone and a few of the skull elements,” Griffin says

Full read at: https://www.scientificamerican.com/article/new-dinosaur-species-is-oldest-ever-found-in-africa/

 

[LeonardoBjj]

I'd be interested to read more about that particular Carcharodontosaurus. I always take these new claims with a big grain or salt until the material is properly studied and published.
That said, I wouldn't be surprised if there were some absolutely gigantic individuals in all of the big theropods. I just hope some get found lol. That said, I think there seems to be a soft upper limit of about rougly 12.5-13 meters for most theropods. That's roughly where all of the big ones seems to top out at, give or take a bit. Some individuals would undoubtedly have surpassed that, but probably not as a species. Barring Spinosaurus possibly since it has a completely different body plan.

- Yeah. I think we are only now found some of the bigger specimen. Even the old uderated Allossaurus had bigger cousins.

But this one will make you happy:

Billions of T. rex likely roamed the Earth, paleontologists report
The iconic predator’s estimated abundance means the T. rex fossils we have today are exceedingly rare.

BYMICHAEL GRESHKO

If you traveled back in time 67 million years ago to ancient Montana, you’d be entering the realm of a tyrant: the iconic predator Tyrannosaurus rex. Before you venture into that lost world, though, you might want to know: On average, how close is the nearest T. rex to you?

That might sound like an impossible thing to know—but after crunching through two decades’ worth of T. rex research, a new study provides estimates of the animal’s population density. In all likelihood, a T. rex would be within 15 miles of you, if not much closer.

The new study, published last Thursday in Science, also translates these population densities into estimates for how many T. rex ever lived. On average, researchers estimate that some 20,000 T. rex lived at any one time and that about 127,000 generations of the dinosaurs lived and died. Those averages imply that a total of 2.5 billion T. rex lived in the species’ native North America, possibly as far north as Alaska and as far south as Mexico, over a two- to three-million-year timespan.

https://www.nationalgeographic.com/science/article/billions-of-t-rex-likely-roamed-the-earth

 

[MLarson]

We like to like to think Dinosaurs were all huge animals but there's small ones as well.
North America's tiniest dinosaur, Fruitadens (sfgate.com)
A new dinosaur species, Fruitadens haagarorum, is the smallest dinosaur ever discovered from North America. The tiny Fruitadens weighed less than a kilogram (two pounds) and was just 70 cm (28 inches) in length. The remarkable fossils of Fruitadens, housed at the Natural History Museum of Los Angeles County were discovered in Colorado in the late 1970s. The species was recently identified and named by an international team of scientists, led by Dr. Richard Butler of the Bavarian State Collection for Paleontology, Munich, Germany, and including Natural History Museum Dinosaur Institute Director Dr. Luis Chiappe. Their findings appear today in the British science journal Proceedings of the Royal Society B.Courtesy Museum of L.A. County/Dinosaur Institute

A giant vampire bat
Desmodus draculae was the largest-known vampire bat to have ever lived. It fed on megafauna, such as the ground sloths. : BatFacts (reddit.com)

 

[LeonardoBjj]

- That's Man-Bat!

 

[LeonardoBjj]

These 7 New Dinosaur Species Were Unearthed In 2022

From carnivores to herbivores, experts find around 50 new species of dinosaurs each year. Here are seven of those finds for 2022.
By Sean MowbrayOct 13, 2022 10:00 AM

1. Guemesia ochoai

Paelontologists in Argentina unearthed a partially complete skull belonging to a stubby-armed abelisaurid. Many of these “armless” dinosaurs possessed even smaller forelimbs than the infamously short-handed Tyrannosaurus rex. It would have roamed during the Late Cretaceous.

Researchers found the skull in the Los Blaquitos Formation in the Northwest of Argentina, though most of the country’s existing abelisaurids have been uncovered in the South, in Patagonia. The new species of carnivore is also smaller than others of its kind, such as the Carnotaurus, according to the paleontologists who made the discovery. In fact, it’s one of the smallest abelisaurids discovered so far.

2. Jakapil kaniukara

The bipedal Jakapil kaniukara is a newly described small, armored dinosaur also discovered in Argentina. Dating from the Cretaceous, the approximately 5-foot-long Jakapil sported bony armor on its neck and back; its discovery makes it the first armored dinosaur from this period to be discovered in South America. The species belongs to the thyreophoran group, which includes other, more famous, juggernauts such as stegosaurus and ankylosaurus.

3. Mbiresaurus raathi

This year, researchers discovered an early ancestor of the towering and lumbering sauropods — a group that includes giants such as the brachiosaurus — in Zimbabwe. Mbiresaurus raathi, however, was a smaller and quicker omnivore. Measuring at around five meters long, it belongs to the sauropodomorph family that gave rise to giant and better-known dinosaurs such as Diplodocus.

Scientists described the nearly complete fossil (lacking only parts of its hands, its ankle bone and skull fragments) in the journal Nature. It takes the title of earliest known dinosaur found in Africa so far, dating back around 230 million years to the late Triassic

4. Perijasaurus lapaz

In August, paleontologists announced the unearthing of a new, nearly 40-foot-long sauropod in Colombia, based on a well-preserved fossilized vertebra. This medium-sized dino would have roamed tropical lowland forested areas during the early- to mid-Jurassic, about 175 million years ago, according to the researchers' description.

Perijasaurus lapaz takes its name fromSerranía del Perijá — where the bone was found — and the Spanish word for peace, as the scientists attribute its discovery to the 2016 peace accord that allowed them to carry out fieldwork in the region.

5. Thanatosdrakon amaru

With an awesome wingspan stretching up to 30 feet, Thanatosdrakon amaru is now the largest pterosaur discovered in South America. Pterosaurs are not actually dinosaurs, but rather flying reptiles. Paleontologists based their newest finding on two specimens found in Argentina, dating from the Cretaceous period, around 86 million years ago.

6. Tuebingosaurus maierfritzorum
Sometimes a new dinosaur is right under your nose … or in the case of paleontologists in Germany, it is stocked in a university collection. Reexamining fossils held by the University of Tübingen, researchers announced the discovery of the herbivorous Tuebingosaurus maierfritzorum.

Previously, its fossils were thought to belong to the bipedal Plateosaurus. But deeper analysis uncovered that T. maierfritzorum almost certainly walked on four legs and is likely related to sauropods, such as Brachiosaurus and Diplodocus. Scientists were tipped off by the specimen’s “broader and more strongly-built hips,” which suggest a life on four legs rather than two.


“Thanatosdrakon is the oldest taxon of the clade Quetzalcoatlinae so far,” the study authors noted. “[F]rom a paleoecological point of view, Thanatosdrakon was found in floodplain deposits of ephemeral meandering systems indicating that this large flying species inhabited continental environments.” Though Thanatosdrakon was freakishly large, it is not the largest of its kind; the enormous Quetzalcoatlus northropi claims that honor.

The 7 Meraxes Giga was already posted here

https://www.discovermagazine.com/planet-earth/these-7-new-dinosaur-species-were-unearthed-in-2022

 

[RoastBeast]

 

[LeonardoBjj]

Andrewsarchus

In popular culture,‭ ‬especially at the turn of the twentieth and twenty-first centuries,‭ ‬Andrewsarchus has been presented as a huge predator,‭ ‬similar in form to other quadrupedal meat eating mammals,‭ ‬but powerfully built like a big cat or even a bear.‭ ‬However despite this reconstruction becoming very familiar in the public consciousness,‭ ‬palaeontologists are far more cautious as so far only the skull of this animal is known.

The popular reconstruction is based upon the concept that for a long time Andrewsarchus was envisioned as a larger relative of Mesonyx,‭ ‬a meat eating predator that is often described as wolf-like,‭ ‬although it actually appeared long before the emergence of true wolves.‭ ‬Later interpretations of Andrewsarchus however‭ (‬one of best known being a‭ ‬2009‭ ‬study by Michelle Spaulding,‭ ‬Maureen A.‭ ‬O’Leary and John Gatesy‭) ‬have since concluded that Andrewsarchus probably isn’t that closely related to Mesonyx.‭ ‬In fact today Andrewsarchus has been widely considered to be closer to primitive hippos or even enteledonts due to the long jaws with wide cheek bones.

The exact diet of Andrewsarchus has also been questioned as the previous older apex predator theories don’t carry as much weight as they used to.‭ ‬Although the jaws would have had tremendously powerful muscles‭ (‬as indicated by the size of the cheek bones‭)‬,‭ ‬most of the teeth in the mouth are not particularly well adapted for any one purpose.‭ ‬The forward canines are the largest and are most useful for getting a grip on things,‭ ‬or perhaps in the case of a carnivore to deliver a killing bite such as puncturing the cranium of a prey animal.‭

‬Because the type specimen skull was found in what would have been a coastal environment during the Eocene,‭ ‬Andrewsarchus has been presented as a beach comber.‭ ‬Here Andrewsarchus may have had a durophagus diet that means it ate shellfish that it dug out with its forward teeth,‭ ‬although it may have included animals like turtles as well as washed up carrion.‭ ‬However while this skull proves that Andrewsarchus was active in coastal areas,‭ ‬it would be a mistake‭ ‬to assume that it was limited to them without the evidence of further remains.

Aside from the skull being similar in form this has also led to some claiming that the behaviour of Andrewsarchus was similar to what has been proposed for enteledonts.‭ ‬This would see Andrewsarchus living the life of an opportunistic omnivore,‭ ‬as while Andrewsarchus is on paper capable of killing its own prey,‭ ‬it may have scavenged carcasses as well as driven off other predators from their kills.‭ ‬The forward teeth could also have been capable of digging up plant tubers that Andrewsarchus could have then eaten.

Since Andrewsarchus had a large skull it would need strong neck muscles to provide ample support.‭ ‬Although we still do‭ ‬not know for certain,‭ ‬it‭’‬s possible that the anterior dorsal vertebrae had enlarged neural spines‭ (‬bony projections that rise upwards from the individual‭ ‬vertebra‭) ‬that provided increased areas for muscle attachment.

‭ ‬This is similar to how some other creatures with large skulls such as enteledonts supported their heads.‭ ‬If true then Andrewsarchus would in life have powerful powerfully built fore quarters which may have given rise to a small hump above its shoulders from the increased muscle mass from this area.

When Andrewsarchus was first compared to Mesonyx its missing body was estimated by scaling up the skull of Mesonyx to that of Andrewsarchus.‭ ‬This led to early size estimates of up to six meters long,‭ ‬something that saw Andrewsarchus being treated as possibly the largest meat eating mammal to ever walk the earth.‭

‬However there are a number of problems with this estimate,‭ ‬the most obvious being the general consensus that Andrewsarchus was not like Mesonyx at all which automatically makes this size comparison flawed.‭ ‬Second is that it is impossible to say how heavily built Andrewsarchus‭ ‬was‭ ‬without seeing how things like muscles could attach to the skeleton.‭

http://www.prehistoric-wildlife.com/species/a/andrewsarchus.html