THe Sherassic Park - A PaLeontologic adventure

[LeonardoBjj]

Swimming secrets of prehistoric reptiles unlocked by new study
Date: April 18, 2023
Source: University of Bristol

Summary: The diverse swimming techniques of the ancient reptiles that ruled the Mesozoic seas have been revealed.

Some of the most extraordinary body transformations in evolution have occurred in animals that adapted to life in water from land-living ancestors, such as modern whales, turtles and seals. During the Mesozoic, from 252 to 66 million years ago, while the dinosaurs stomped about on land, many groups of reptiles took to the seas, such as the iconic ichthyosaurs, plesiosaurs, crocodiles and mosasaurs.

In a new paper, published in the journal Palaeontology, a Bristol team of palaeobiologists used state-of-the-art statistical methods to perform a large-scale quantitative study, the first of its kind, on the locomotion of Mesozoic marine reptiles.

The researchers collected measurements from 125 fossilised skeletons, and used these to explore changes in swimming styles within lineages and through time, discovering that there was no explosive radiation at the beginning of the Mesozoic, but a gradual diversification of locomotory modes, which peaked in the Cretaceous period.

Lead author Dr Susana Gutarra of Bristol's School of Earth Sciences said: "Changes in anatomy in land-to-sea transitions are intimately linked to the evolution of swimming. For example, sea lions' flippers have relatively short forearm and large hands, very different from the walking legs of their ancestors. The rich fossil record of Mesozoic marine reptiles provided great opportunity to study these transitions at a large scale."

Co-author Beatrice Heighton, said: "We included measurements from living aquatic animals, such as otters, seals and turtles, of which we know their swimming behaviour. This is very important to provide a functional reference for the ancient species, with unknown swimming modes."

In the aftermath of the end-Permian extinction, about 250 million years ago, various groups of reptiles became aquatic hunters, populating the early Mesozoic seas.

Co-author Dr Tom Stubbs said: "After this devastating event, there was a gradual diversification of locomotory modes, which contrasts with the rapid radiation described previously for feeding strategies. This is fascinating because it suggests a 'head-first' pattern of evolution in certain lineages."

This paper sheds light into the swimming of specific groups. Dr Ben Moon explained: "Ichthyosaurs were highly specialised for aquatic locomotion from very early in their evolution. This includes their close relatives, the hupehsuchians, which had a morphology unlike any other known aquatic tetrapod. Further, we see overlap between mosasaurs and ichthyosaurs, which is indicative that mosasaurs evolved a swimming mode by oscillating flukes, different from the eel-like body undulation suggested in the past.

"In contrast, we don't find evidence of convergence between ichthyosaurs and metriorhynchids (the highly aquatic crocodyliform thalattosuchians). This group retained quite primitive-looking hindlimbs, which seems incompatible with swimming by fluke oscillation."

This study also delves into the evolution of size, a feature related to locomotion, animal physiology and ocean productivity. Professor Mike Benton said: "We know that transition to life in water is usually accompanied by an increase in body mass, as seen in cetaceans, and one of our previous studies shows that large sizes benefit aquatic animals in reducing the mass-specific costs of drag. Thus, it was essential to explore this trait in the wider ensemble of Mesozoic marine reptiles."

Dr Gutarra added: "Body size follows a similar trend to the diversification of locomotory modes, and the widest spread of body size also occurred in the Cretaceous, confirming a strong connection between the two. The rate of increase and the maximum limits to body size seems to vary a lot between groups. This is a fascinating observation. We need to explore further what factors influence and limit the increase in body mass in each group."

https://www.sciencedaily.com/releases/2023/04/230418101425.htm

 

[LeonardoBjj]

The Last of the Rhinoceros Titans

BY RILEY BLACK

In paleontology, size matters. The lifestyles of the large and charismatic often gain far more attention those of smaller, equally-strange creatures that thrived alongside the leviathans during prehistory. The most massive dinosaurs, of course, are the recipients of such scale-dependent adoration, and the same is true of the great extinct rhinoceros Paraceratherium (or “Indricotherium“, or “Baluchitherium“, or “Dzungariotherium“, but I’ll get to that in a moment.)

Stretching over 26 feet long, and often said to weigh as much as five elephants, Paraceratherium has traditionally been heralded as the largest mammal ever to tromp over the Earth. The enormous rhino is practically required to make appearances in books, documentaries, and museum displays about fossil mammals. Yet, as paleontologist Donald Prothero demonstrates in his new book Rhinoceros Giants, old misconceptions about Paraceratherium cling to our imagination even as paleontologists are slowly piecing together a more complete picture of the superlative mammal.

For paleontology aficionados, the majesty of Paraceratherium is self-evident. The rhino was far larger than any alive today, and was an iconic member of mammal faunas that roamed Eurasia between about 35 and 20 million years ago. But Prothero spends no time trying to draw in those who are not already enamored with the titan. The first chapter of the relatively slim book – “Quicksand!” – jumps right into the romantic tales of fossil rhino discoveries in Mongolia during the American Museum of Natural History’s celebrated 1920s expeditions to the region. There is no introduction to what the giant rhinos were, or even why we should care at all that they existed.

https://www.nationalgeographic.com/science/article/the-last-of-the-rhinoceros-titans


http://www.prehistoric-wildlife.com/species/p/paraceratherium.html

 

[LeonardoBjj]

Male Woolly Mammoths Had Testosterone-Fueled Aggressive Episodes

By studying preserved tusks, scientists suggest the mammals experienced a yearly condition known as musth, like male elephants do today
Sarah Kuta
Daily Correspondent
May 4, 2023

Once a year, adult male Asian and African elephants go through musth, or a period when their reproductive hormone levels—including testosterone—surge, and they act more aggressive and unpredictable.

Paleontologists have long wondered if male woolly mammoths—modern elephants’ extinct relatives—also experienced this condition, which appears to have a breeding purpose. Now, thanks to a cleverly designed study, published Wednesday in the journal Nature, researchers at the University of Michigan have uncovered evidence that suggests mammoths also went through musth when they roamed the Earth during the Pleistocene and Holocene epochs.


Mammoth and elephant tusks are like tree trunks in that they grow in concentric rings and, in the process, capture information about an animal’s diet, lifestyle and condition throughout its lifetime. As Ashley Strickland writes for CNN, they’re like “time capsules.” This information is stored in layers of dentin—the material that’s in all teeth, as tusks are elongated upper incisors. Dentin can contain valuable endocrine data, or traces of hormones, and it doesn’t easily degrade, making it a prime contender for studying the lives of animals, even very old ones.

Armed with this knowledge, scientists suspected that mammoths’ tusks might hold the answer to the musth question. To that end, they took samples from various points along the tusks of an adult male African elephant killed by a hunter in 1963, a male woolly mammoth that lived between 33,291 to 38,866 years ago and a female wooly mammoth that lived between 5,597 to 5,885 years ago, according to a statement. Then, they analyzed the samples, isolated the hormone levels in each one and compared them across time and with one another.

As expected, the female wooly mammoth’s testosterone levels changed very little throughout her life. But both male animals experienced big fluctuations of the hormone: The analysis of the African elephant’s tusk showed its testosterone levels increased to 20 times higher than normal during musth. The male wooly mammoth, meanwhile, periodically experienced testosterone levels ten times higher than normal, which the researchers concluded meant the extinct animal also went through musth.

Full read at: https://www.smithsonianmag.com/smart-news/male-woolly-mammoths-had-testosterone-fueled-aggressive-episodes-180982125/

 

[AGGAMEMNON66]

Where is the sherbro that thought the T-Rex was the biggest dinosaur? It's like he never got a dinosaur book as a kid.

Pretty sure Godzilla is a T-Rex so his opinion checks out

 

[Thrawn33]

Deinonychus was always my favorite, long before Jurassic Park took them and called them Raptors.

Also they will never have feathers in my minds eye.

 

[LeonardoBjj]

Deinonychus was always my favorite, long before Jurassic Park took them and called them Raptors.

Also they will never have feathers in my minds eye.

- The same with me. Would ruin my childhood memories.

 

[NoSmilez]

Pretty sure Godzilla is a T-Rex so his opinion checks out

Ewww what kinda Godzilla fan are you? He is a Godzillasaurus.

 

[LeonardoBjj]

New dinosaur with blade-like spikes for armor discovered on UK’s Isle of Wight

By Jack Guy, CNN
Published 7:52 AM EDT, Fri June 16, 2023

CNN — A new species of dinosaur with blade-like spikes for armor has been discovered on the Isle of Wight, off the south coast of England.

Named Vectipelta barretti, it is the first armored dinosaur, or ankylosaur, to have been found on the island in 142 years, according to a statement from London’s Natural History Museum, where several of the researchers who discovered the dinosaur work.

The dinosaur would have lived during the Early Cretaceous period, 145-100.5 million years ago, the museum said.

There are few fossils dating from the period worldwide, which some believe suggests there was a mass extinction at the end of the Jurassic period, which preceded it.

Given the lack of fossil record from the Early Cretaceous period in other parts of the world, the Isle of Wight is vitally important for our understanding of what happened, the museum said.

“This is an important specimen because it sheds light on ankylosaur diversity within the Wessex formation and Early Cretaceous England,” said study lead author Stuart Pond, a researcher at the Natural History Museum.

“For virtually 142 years, all ankylosaur remains from the Isle of Wight have been assigned to Polacanthus foxii, a famous dinosaur from the island, now all of those finds need to be revisited because we’ve described this new species.”

“For virtually 142 years, all ankylosaur remains from the Isle of Wight have been assigned to Polacanthus foxii, a famous dinosaur from the island, now all of those finds need to be revisited because we’ve described this new species.”

The new species has several differences to Polacanthus foxii, which was previously the only ankylosaur known to have lived on the island, with variations in neck and back vertebrae, as well as the pelvis and the spiked armor.

The team’s analysis showed that Vectipelta barretti is most closely related to Chinese ankylosaurs, suggesting dinosaurs were able to move between Asia and Europe in the Early Cretaceous.

The new species has several differences to Polacanthus foxii, which was previously the only ankylosaur known to have lived on the island, with variations in neck and back vertebrae, as well as the pelvis and the spiked armor.

The team’s analysis showed that Vectipelta barretti is most closely related to Chinese ankylosaurs, suggesting dinosaurs were able to move between Asia and Europe in the Early Cretaceous.

It would have measured more than 10 meters (about 33 feet) in length and weighed several tons, making it one of Europe’s biggest land-based hunters.

https://edition.cnn.com/2023/06/16/uk/new-dinosaur-vectipelta-barretti-scli-intl-scn-gbr/index.html

 

[MLarson]

https://prehistoric-fauna.com/Whollydooleya-tomnpatrichorum

A newfound extinct marsupial "hypercarnivore" from Australia — one that researchers say looked like a cross between a Tasmanian devil and a hyena — was about twice as big as Australia's largest living flesh-eating marsupials, a new study finds.

 

[MLarson]

Armadillosuchus arrudai • An armadillo-like sphagesaurid crocodyliform from the Late Cretaceous of Brazil
https://novataxa.blogspot.com/2012/02/2009-armadillosuchus-arrudai.html?m=1

 

[MLarson]

Several million years ago, the smallest mammoths in the history lived on the island Crete, being even in the adulthood comparable in size to modern baby elephants. This is very surprising and interesting.

The adult «Mammuthus creticus» weighted less than 300 kilograms and his height at the withers was about one meter.

The first fossils of the Cretan mammoth were found back in 1904 by Dorothea Bate, known at the time as fossil hunter. However, initially they were incorrectly identified as belonging to “Palaeoloxodon creticus”, allegedly a relative of the dwarf elephant from Crete, having straights tusks and already known. Although the found teeth were very similar to those of a mammoth, scientists of the early 20th century just could not believe that exactly two types of dwarf Proboscidea could live together on the one island.
https://thenewgreece.com/en/nature/the-worlds-smallest-mammoth-lived-in-crete/

 

[MLarson]

One look at Platybelodon and you know why the beast has been called a shovel-tusker. The publication describing one of the most abundant species, Platybelodon grangeri, even went so far as to illustrate the lower jaw of one of these fossil elephants next to a shovel in case the resemblance wasn't immediately clear. But appearances can deceive. As it turns out, Platybelodon wasn't a shovel-tusker. It may have been more of a saw-tusker.
Shovel-Tusker Was Actually a Saw-Tusker - Scientific American Blog Network

 

[MLarson]

A tiny pterosaur fossil was discovered in the western part of China's Liaoning Province. It is currently the smallest of the species of flying pterosaurs ever found in the world.

t pterosaur fossil found in China -- china.org.cn

 

[MLarson]

Giant Panda's Ancient 'Cousin,' Agriarctos Beatrix, Discovered In Spain | HuffPost Impact
"This kind of bear was small, even smaller than the Malayan sun bear, the smallest found today," paleobiologist Juan Abella of the Museo Nacional de Ciencias Naturales, who was part of the research team behind this discovery, said in a written statement.

 

[LeonardoBjj]

Paleontologists identify two new species of sabertooth cat

Date: July 20, 2023
Source: Cell Press
Summary: Sabertooth cats make up a diverse group of long-toothed predators that roamed Africa around 6-7 million years ago, around the time that hominins -- the group that includes modern humans -- began to evolve. By examining one of the largest global Pliocene collections of fossils in Langebaanweg, north of Cape Town in South Africa, researchers present two new sabertooth species and the first family tree of the region's ancient sabertooths. Their results suggest that the distribution of sabertooths throughout ancient Africa might have been different than previously assumed, and the study provides important information about Africa's paleoenvironment.

"The known material of sabertooths from Langebaanweg was relatively poor, and the importance of these sabertoothed cats has not been properly recognized," says senior author Alberto Valenciano, a paleontologist at Complutense University. "Our phylogenetic analysis is the first one to take Langebaanweg species into consideration."

The study described a total of four species. Two of these species, Dinofelis werdelini and Lokotunjailurus chimsamyae, were previously unknown. Dinofelis sabertooths are globally distributed, and their fossils have been found in Africa, China, Europe, and North America. The researchers were expecting to identify a new Dinofelis species from Langebaanweg based on prior research. However, Lokotunjailurus has only ever been identified in Kenya and Chad before this analysis. This suggests that they may have been distributed all throughout Africa between 5-7 million years ago.

Valenciano was a postdoctoral fellow at the Iziko Museums of South Africa, which houses all the sabertooth fossils that were analyzed in this study. A team of colleagues from China, South Africa, and Spain put the final project together. To construct a family tree, the researchers classified the physical traits of each sabertooth species -- such as presence or absence of teeth, jaw and skull shape, and tooth structure -- and coded this information into a matrix that could determine how closely related each sabertooth was to its evolutionary cousins.

The resulting population composition of Langebaanweg sabertooths (Machairodontini, Metailurini, and Feline) reflects the increasing global temperatures and environmental changes of the Pliocene epoch. For instance, the presence of Machairodontini cats, which are larger in size and more adapted to running at high speeds, suggests that there were open grassland environments at Langebaanweg. However, the presence of the Metailurini cats suggests that there were also more covered environments, such as forests. While the fact that researchers found both Metailurine and Machairodonti species suggests that Langebaanweg contained a mixture of forest and grassland 5.2 million years ago, the high proportion of Machairodonti species compared with other fossil localities from Eurasia and Africa confirm that southern Africa was transitioning toward more open grasslands during this period.

"The continuous aridification throughout the Mio-Pliocene, with the spread of open environments, could be an important trigger on the bipedalism of hominids," the authors write. "The sabertooth guild in Langebaanweg and its environmental and paleobiogeographic implications provide background for future discussion on hominid origination and evolution."

Interestingly, the researchers also note that the composition of sabertooths in Langebaanweg closely mirrors that of Yuanmou, China. Yuanmou's Longchuansmilus sabertooths might even have a close evolutionary relationship with Africa's Lokotunjailurus species.

"This suggests that the ancient environment of the two regions was similar or that there was a potential migration route between the Langebaanweg and Yuanmou," says first author Qigao Jiangzuo, a paleontologist at Peking University.

More fossil evidence could help paleontologists understand exactly how these two sites are related. "The two new sabertooths are only an example of the numerous unpublished fossils from Langebaanweg housed at Iziko in the Cenozoic Collections," says Romala Govender, a curator and paleontologist at the Iziko Museums in South Africa. "This brings to the fore the need for new and detailed studies of Langebaanweg fauna."

https://www.sciencedaily.com/releases/2023/07/230720124855.htm

 

[blaseblase]

Imagine living with these things walking around.

10 feet tall, 300 lbs, massive beak, and runs as fast as a horse.

 

[LeonardoBjj]

New dinosaur species discovered in Thailand

by Bob Yirka

A multi-institutional team of paleontologists has identified a new dinosaur species dug up in Thailand in 2012. In their paper published in the journal Diversity, the group describes where the fossil was found, its characteristics and its condition.

The fossil was uncovered at a dig site in Phu Noi, in Northern Thailand. The geological area is known as the Phu Kradung Formation. The dig site has yielded a large number of fossils over the years. In this new effort, the research team focused their effort on a fossil embedded in stone that was in good condition. It is a previously unknown species, now named Minimocursor phunoiensis.

The research team describes the fossil as an "exceptionally articulate skeleton," and suggest it is one the most well-preserved dinosaurs ever discovered in Southeast Asia. They found it to be of the neornithischian clade, which were plant-eating dinosaurs.

The researchers also found that the dinosaur was not yet mature when it died. It had four limbs but walked on two legs. It also had a long body and long tail, and a beak-like snout with a bony lump on its jaw known as a jugal boss. It also had a ridge along its pelvis. It has been dated to 145 to 163 million years ago. The team estimates that when full grown, the dinosaur would have been approximately 2 meters long.

Overall, its physical characteristics suggest it ate vegetation and was able to run quite fast to avoid being eaten by predators. The researchers note that other fossils of the same type of dinosaur have been found in the same general area, suggesting that they were very common.

The team concludes by noting that study of the fossil is still underway; some of its bones still need processing, including its skull. Once that is complete, they add, much more will be learned about the dinosaur and its place among others of its time.

https://phys.org/news/2023-07-dinosaur-species-thailand.html

 

[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.

Newly discovered whale species could have been heaviest animal ever

Fossils found in Peru from extinct species show it may have had body mass of 85-340 tonnes – heavier than blue whales

Reconstruction of Perucetus colossus in its coastal habitat, with an estimated body length of 20 metres. Photograph: Alberto Gennari

The fossilised bones of an ancient creature that patrolled coastal waters 40m years ago belong to a newly discovered species that is a contender for the heaviest animal ever to have existed on Earth.

Fossil hunters discovered remnants of the enormous and long-extinct whale in a rock formation in the Ica desert of southern Peru. Fully grown adults might have weighed hundreds of tonnes, researchers believe.

“It was very unlike anything I had seen before,” said Alberto Collareta, a palaeontologist at the University of Pisa who worked on the fossils. It is “the heaviest skeleton as far as mammals are concerned, possibly the heaviest vertebrate ever”, he said.

Until now, the blue whale was widely regarded to hold the record for the animal with the largest body size. The giant skeleton of Hope, the blue whale that looms over visitors to the Natural History Museum in London, is more than 25 metres long and weighs 4.5 tonnes.

But the new species, named Perucetus colossus after the country of origin and its gigantic size, could have grown larger and heavier than the blue whale, the scientists said. Despite being a mere 20 metres long, the skeleton of P. colossus would have been two to three times heavier than that of a 25-metre blue whale because of its denser bones. Its body mass would have come in at 85 to 340 tonnes, they estimated.

The researchers reached the conclusion after comparing 13 vertebrae, four ribs and a single hip bone from P. colossus with bones from close whale relatives. Beyond its vast size, P. colossus appears to have had forelimbs for walking on the seabed and little, vestigial hind limbs.

“If we look at the most conservative estimate of 85 tonnes [for the newly discovered animal], we are definitely in the ballpark of the blue whale, which is the largest animal known to date,” said Eli Amson, a specialist in mammal fossils at the State Museum of Natural History in Stuttgart. “Maybe there’s some single individuals of blue whales that were much larger, but maybe from this new species there are also much larger individuals.”

Writing in the journal Nature, Collareta and colleagues described how the fossils were discovered 13 years ago but took many years to prepare for study. Unlike most whales, which have relatively light skeletons and can prey on fast-moving fish and other marine creatures, P. colossus had heavier bones and was more likely a slow-swimming scavenger.

Amson said the find offered important insights about gigantism in early cetaceans – animals that include dolphins, whales and porpoises – adding that while blue whales and their ancestors are usually found in open-sea environments, the newly discovered animal evolved in shallow coastal waters.

Travis Park, a postdoctoral researcher and fellow at the Natural History Museum in London, who was not involved in the work, said the discovery suggested cetaceans achieved extreme body masses about 30m years earlier than previously thought. Other large basilosaurids, or ancient whales, that lived alongside P. colossus were probably more slender, serpentine, and flexible, making the animal very different from any cetacean previously known from the middle Eocene.

“It shows us that we still have lots to learn about what cetaceans were capable of doing prior to the evolution of the modern groups,” Park said.

https://www.theguardian.com/science...-species-could-have-been-heaviest-animal-ever

 

[MLarson]

New dinosaur species discovered in Thailand

by Bob Yirka

A multi-institutional team of paleontologists has identified a new dinosaur species dug up in Thailand in 2012. In their paper published in the journal Diversity, the group describes where the fossil was found, its characteristics and its condition.

The fossil was uncovered at a dig site in Phu Noi, in Northern Thailand. The geological area is known as the Phu Kradung Formation. The dig site has yielded a large number of fossils over the years. In this new effort, the research team focused their effort on a fossil embedded in stone that was in good condition. It is a previously unknown species, now named Minimocursor phunoiensis.

The research team describes the fossil as an "exceptionally articulate skeleton," and suggest it is one the most well-preserved dinosaurs ever discovered in Southeast Asia. They found it to be of the neornithischian clade, which were plant-eating dinosaurs.

The researchers also found that the dinosaur was not yet mature when it died. It had four limbs but walked on two legs. It also had a long body and long tail, and a beak-like snout with a bony lump on its jaw known as a jugal boss. It also had a ridge along its pelvis. It has been dated to 145 to 163 million years ago. The team estimates that when full grown, the dinosaur would have been approximately 2 meters long.

Overall, its physical characteristics suggest it ate vegetation and was able to run quite fast to avoid being eaten by predators. The researchers note that other fossils of the same type of dinosaur have been found in the same general area, suggesting that they were very common.

The team concludes by noting that study of the fossil is still underway; some of its bones still need processing, including its skull. Once that is complete, they add, much more will be learned about the dinosaur and its place among others of its time.

https://phys.org/news/2023-07-dinosaur-species-thailand.html

From Thailand? Is it called Ladyboysoreass?

 

[FyrFytr998]

From Thailand? Is called Ladyboysoreass?