Pre-dinosaur carnivorous reptile discovery in Tanzania


This 2010 video says about itself:

Just testing out some software that records cursor movements. This is a Photoshop sketch of an extinct archosaur called a rauisuchian. They were related to crocodilians and distant cousins of the dinosaurs.

From Science, Space & Robots:

Partial Skel[e]ton of Ancient Croc-like Predator Species Discovered

Nundasuchus was a 9-foot long predator croc-like species that lived before the dinosaurs. It had steak knife-teeth and bony plates on its back. A partial skeleton of the species was discovered in 2007.

Nundasuchus songeaensis was named by Sterling Nesbitt, an assistant professor of geological sciences and member of the Virginia Tech paleontology team. Nesbitt says the name is “Swahili mixed with Greek.” Nunda means predator in Swahili and suchus refers to a crocodile in Greek. Songeaensis is named for the town of Songea where the creature’s bones were discovered.

Nesbitt says in a statement, “The reptile itself was heavy-bodied with limbs under its body like a dinosaur, or bird, but with bony plates on its back like a crocodilian.”

The fossil of Nundasuchus was found in southwestern Tanzania. The bones were in thousands of pieces and Nesbitt says over 1,000 hours were spent cleaning them and putting them together.

Nesbitt also says, “There’s such a huge gap in our understanding around the time when the common ancestor of birds and crocodilians was alive – there isn’t a lot out there in the fossil record from that part of the reptile family tree. This helps us fill in some gaps in the reptile family tree, but we’re still studying it and figuring out the implications.”

A research paper on the reptile can be found here in the Journal of Vertebrate Paleontology.

Posted on January 20, 2015

Triassic fossil reptile discovery in Dutch museum


This video says about itself:

21 March 2013

An overview of reptiles found in Triassic marine ecosystems.

Translated from daily De Gelderlander in the Netherlands:

Prehistoric marine reptile from Winterswijk ‘discovered’

January 9, 2015

ENSCHEDE WINTERSWIJK – Researchers from the Universities of Bonn and Zurich have recently ‘discovered’ a placodont in the collection of Museum TwentseWelle. The remains of the marine reptile were found in the late 1980’s in the quarry in Winterswijk by Gerben Diepenbroek from Varsseveld.

Diepenbroek gave his collection in 2008 to the museum in Enschede. Since then the collection is a subject of investigation by various universities in Europe.

According to Dennis Nieweg, nature department curator of TwentseWelle, it is a very special discovery. “Worldwide but a few placodonts are known.”

245 million years

The placodont is a marine reptile that lived some 245 million years ago in shallow waters, ”grazing’ seabeds looking for small animals such as sea urchins and crabs. According to Nieweg the discovery of this placodont improves our understanding of how the Netherlands was like 245 million years ago. The region around Winterswijk was under water then and was part of an inland sea covering the Netherlands.

The fossil remains of this sea reptile are again in Enschede after all investigations. Museum TwentseWelle shows them in a special showcase.

Triassic flying fish discovery in China


This video is called BBC Life – Flying Fish.

From Biology Letters:

A Middle Triassic thoracopterid from China highlights the evolutionary origin of overwater gliding in early ray-finned fishes

Guang-Hui Xu, Li-Jun Zhao, Chen-Chen Shen

January 2015

Abstract

Gliding adaptations in thoracopterid flying fishes represent a remarkable case of convergent evolution of overwater gliding strategy with modern exocoetid flying fishes, but the evolutionary origin of this strategy was poorly known in the thoracopterids because of lack of transitional forms.

Until recently, all thoracopterids, from the Late Triassic of Austria and Italy and the Middle Triassic of South China, were highly specialized ‘four-winged’ gliders in having wing-like paired fins and an asymmetrical caudal fin with the lower caudal lobe notably larger than the upper lobe.

Here, we show that the new genus Wushaichthys and the previously alleged ‘peltopleurid’ Peripeltopleurus, from the Middle Triassic (Ladinian, 235–242 Ma) of South China and near the Ladinian/Anisian boundary of southern Switzerland and northern Italy, respectively, represent the most primitive and oldest known thoracopterids.

Wushaichthys, the most basal thoracopterid, shows certain derived features of this group in the skull. Peripeltopleurus shows a condition intermediate between Wushaichthys and Thoracopterus in having a slightly asymmetrical caudal fin but still lacking wing-like paired fins. Phylogenetic studies suggest that the evolution of overwater gliding of thoracopterids was gradual in nature; a four-stage adaption following the ‘cranial specialization–asymmetrical caudal fin–enlarged paired fins–scale reduction’ sequence has been recognized in thoracopterid evolution. Moreover, Wushaichthys and Peripeltopleurus bear hooklets on the anal fin of supposed males, resembling those of modern viviparious teleosts. Early thoracopterids probably had evolved a live-bearing reproductive strategy.

South African Triassic carnivorous reptile Garjainia


This video says about itself:

Palaeodigs part 2 Giant amphibians and Early archosaurs

1 November 2013

Part 2/2 of a two part special recorded at excavations in Krasiejów, SW Poland. In this video I interview special guest Mateusz Tałanda about the amazing fossils found at Krasiejów. Sound and camera are a little poor, sorry.

From Laelaps blog today:

Big-Headed Carnivore a Sign of Triassic Recovery

by Brian Switek

I’ve spent much of my weekend writing about Jurassic World. I won’t rehash the details here – you can read those over at VICE – but it struck me how easy it is to talk about paleontology when everyone knows the animals you’re discussing. I don’t have to explain who Tyrannosaurus or Velociraptor were, and, from museums and movies, most everyone has some idea of what a dinosaur is.

But if Colin Trevorrow were directing Triassic World, my job would be a lot more difficult. With the exception of the first dinosaurs, and maybe the “armadillodiles“, most of the strange creatures that thrived between 252 and 200 million years ago don’t have common names or much presence at all in the public consciousness. So you’re going to have to bear with me for a second while I introduce you to Garjainia madiba.

Discovered in the 247 million year old rock of South Africa, and described by Natural History Museum, London paleontologist David Gower and colleagues in PLoS One, Garjainia madiba belonged to a group of carnivores called erythrosuchid archosauriforms. Let’s unpack that.

You know birds and crocodiles? They’re the two living lineages of a group of animals called archosaurs – the “ruling reptiles” – that, in turn, were part of a larger radiation of critters called archosauriforms. So lower down on the tree, close to the roots, there was a lineage of predatory archosauriforms called erythrosuchids to which Garjainia belonged. To give it a little more context, Garjainia madiba was archaic enough that, in hindsight, we can say it’s equally-closely-related to birds and crocodiles. Garjainia and its carnivorous kin evolved before that great split in the archosauriform family tree.

The animal that Gower and coauthors describe is not the first of its kind. The first species of Garjainia was described in 1958 from fossils uncovered in Russia. What makes the new species special is that it’s a little older and living in a different region, and, as long as you’re looking at the skull, it’s easy to tell the two species apart. The South African species, Garjainia madiba, has bulbous bosses of bone behind its eye and on its cheek that are lacking in the other species. Why this animal had these bumps isn’t yet clear – perhaps they were sign of maturity, differences between the sexes, or something else – but they’re among the traits that mark Garjainia madiba as a new species.

And in terms of size, Garjainia madiba was large enough to take on a variety of prey. Gower and colleagues estimate that the animal grew to over eight feet long, with a significant portion of that being a big, narrow-snouted skull. But what makes Garjainia madiba remarkable is not its fearsome appearance. The real story is in its bones.

Gower and colleagues examined thin sections of seven Garjainia madiba limb bones from individuals of different sizes. Inside, they found signs of rapid growth – relatively messy organization riddled with vascular canals and newly-made bone structures called primary osteons. Even in Garjainia that had periodic stopping points in their growth, likely in response to dry seasons or other times of stress, the bone in between those lines show quick growth spurts.

These starts and stops might explain why the archosauriforms, and not the surviving protomammals, came to rule the Triassic. Garjainia madiba and its relatives may have outpaced our own ancestors and cousins in terms of their life cycle, growing faster and reaching sexual maturity earlier. Simply put, the archosauriforms may have simply out-reproduced the protomammals, letting them evolve more quickly and limiting niches the protomammals could then create.

This archosauriform takeover happened quickly. Garjainia madiba lived a scant five million years after the worst mass extinction of all time – the end-Permian catastrophe that eliminated over 90% of species in the seas and over 75% of species on land. It’s a sign of a rapid burst of evolutionary novelty that paleontologists are truly just beginning to track. In the earliest days of the Triassic, life was bouncing back, with the archosauriforms leading the way.

[For more, read Mark Witton’s account of illustrating Garjainia.]

Reference: Gower, D., Hancox, P., Botha-Brink, J., Sennikov, A., Burlet, R. 2014. A new species of Garjainia Ochev, 1958 (Diapsida: Archosauriformes: Erythrosuchidae) from the Early Triassic of South Africa. PLoS One. 9, 11: e111154. doi: 10.1371/journal.pone.0111154

Ancient mammals discovery in China


This video is called Ancient Mammals. Mammal evolution from the Triassic to now.

From Science News:

Fossils push back origins of modern mammals

Common ancestor evolved over 200 million years ago

by Meghan Rosen

2:39pm, September 10, 2014

Modern mammals’ ancestors may have emerged millions of years earlier than scientists suspected — around the time the first dinosaurs roamed the Earth.

The fossilized remains of six little tree-dwelling animals push the lineage of today’s mammals back to the Late Triassic, more than 200 million years ago, researchers report September 10 in Nature.

“That’s really, really old,” says paleontologist Robert Asher of the University of Cambridge, who was not involved with the work. Scientists had thought that the common ancestor of those animals originated sometime in the Jurassic, he says. “This is very exciting stuff.”

Xianshou songae is the name of the newly discovered dinosaur age mammal.

Oldest reptile live birth fossil discovery


This video is called The history of paleoillustrations: Ichthyosauria.

From LiveScience:

Oldest Fossil of Reptile Live Birth Found

By Becky Oskin, Staff Writer | February 12, 2014 05:04pm ET

A new fossil that captures both birth and death reveals the earliest ancestors of the giant prehistoric sea predators called ichthyosaurs birthed their babies headfirst, according to a new study.

The fossil of an ancient Chaohusaurus mother that likely died while in labor also suggests that reptilian live birth only evolved on land, researchers report today (Feb. 12) in the journal PLOS ONE.

Ichthyosaurs were top ocean predators during the age of the dinosaurs. Sleek, streamlined swimmers that grew as long as a bus, they had teeth-filled snouts and enormous eyes for snatching prey. These air-breathing carnivores arose from land reptiles that moved into the water from land during the early Triassic period, between 251 million and 247 million years ago. (The Triassic period follows one of the biggest mass extinctions on Earth, which killed 96 percent of marine species and 70 percent of land species.) [Image Gallery: Ancient Monsters of the Sea]

Previously found fossils of pregnant ichthyosaurs had already revealed the reptiles carried live embryos, not eggs. And one spectacular fossil of a Stenopterygius ichthyosaur in “childbirth,” from the Jurassic period, between 201 million and 145 million years ago, showed at least one species had newborns come out tail-first.

However, researchers didn’t know whether the earliest ichthyosaurs also gave birth headfirst or tail-first. Most air-breathing marine creatures that bear live young, such as whales and dolphins, birth their babies tail-first, so the newborns don’t suffocate during labor. But on land, babies tend to come out headfirst. And the earliest whales, which also evolved from land mammals, birthed their newborns headfirst.

The new fossil confirms that the first ichthyosaur babies came out headfirst, the study reports. The ichthyosaur mother died with three young: one outside the mother, one half-emerged headfirst from her pelvis and one still inside, waiting to be born. Because of the burial positions, it’s unlikely the babies were expelled from the mother after death, the researchers said.

“The reason for this animal dying is likely difficulty in labor,” said Ryosuke Motani, lead study author and a paleobiologist at the University of California, Davis. Motani believes the first baby was born dead, and the mother may have died of a labor complication from the second, which is stuck half-in, half-out of her body. “Obviously, the mother had some complications,” he said.

The skeleton was a lucky find. It was hidden in a rock slab with a Saurichthys fish fossil, and was only discovered when the fish fossil was prepared in the team’s lab in China. (The two fossils aren’t from the same time period, the researchers said.)

The Chaohusaurus fossil, from one of the oldest ichthyosaur species, is about 10 million years older than other fossil embryos from reptiles found so far.

The specimen is now at the Anhui Geological Museum in Hefei, China. The team recovered more than 80 new ichthyosaur skeletons during a recent field expedition to a fossil quarry in south Majiashan, China.

Earliest newborns

Live birth evolved independently in more than 140 different species, including about 100 reptiles. Other extinct aquatic reptiles that gave birth to live young include the plesiosaur and the mosasaur; in 2011, scientists discovered a pregnant plesiosaur, a marine reptile, which lived some 78 million years ago.

The new ichthyosaur fossil pushes back the known records of live birth to the earliest appearance of marine reptiles 248 million years ago, during the beginning of the Mesozoic era.

Until now, researchers thought live birth first appeared in marine reptiles after they took to the seas, Motani said. The ichthyosaur fossil counters this assumption, by providing an evolutionary link to the headfirst, terrestrial style of childbirth.

“This land-style of giving birth is only possible if they inherited it from their land ancestors,” Motani told Live Science. “They wouldn’t do it if live birth evolved in water.”

And because ichthyosaurs evolved from land reptiles, the discovery suggests that land reptiles also bore live young in the earliest Mesozoic, Motani said. The oldest fossil evidence for live birth in land reptiles is no more than 125 million years old, more than 100 million years younger than the new fossil discovery.

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Big Triassic reptiles discovery in Texas


This video says about itself:

Texas Tech University Scientists Discover Prehistoric Crocodile Species

28 Jan 2014

Texas Tech scientists recently discovered a new species of phytosaur, which is like a modern-day crocodile. The skull was found near Post, Texas, and is believed to be 210 million years old.

Though phytosaurs look like crocodiles, there is doubt how closely related to them they were.

Today, not only news from China about the discovery of a gigantic dinosaur from the Cretaceous age.

Also news from Texas in the USA about the discovery of another reptile species; much older; smaller, but still big.

From Texas Tech University today:

Paleontologists discover new Triassic swamp monster (w/ Video)

18 hours ago by John Davis

In the dangerous waters of an ancient oxbow lake created by a flooded and unnamed meandering river, the female phytosaur died and sank to the bottom 205 million years ago. About 40 yards away the remains of a larger male also came to rest, and both disappeared in a tomb of soil and sediment.

Evidence for the cause of their deaths and the rest of their bodies have vanished with time, but their skulls remained. After careful research, a Texas Tech paleontologist says he and others have discovered a new species of the Triassic-age monster in the wilds of West Texas.

Their findings were published in the peer-reviewed journal, Earth and Environmental Science Transactions of the Royal Society of Edinburgh.

Bill Mueller, assistant curator of Paleontology at the Museum of Texas Tech University, said the team named their find Machaeroprosopus lottorum after the Lott family who own the ranch on which the animal was discovered.

“We found them in an area we’d been excavating in,” Mueller said. “I think we’ve gotten four skulls out of that area already. Doug Cunningham found this specimen, and then we dug it up. When he found it, just the very back end of the skull was sticking out of the ground. The rest was buried. We excavated it and brought it into the museum to finish preparation.”

Cunningham, currently a field research assistant at the museum and a retired firefighter, remembered finding the unusual female skull on June 27, 2001. After removing it from the mudstone, he recalls looking it over carefully with others and wondering if his discovery would add a new animal to science.

“It was really well preserved with the teeth and everything,” Cunningham said. “Finding one with teeth is pretty rare. It was so odd, but when they come out of the ground, you have a long way to go to actually see what you have because they’re still covered in matrix. We were all kind of in awe of it. It had this long, skinny snout. It was quite a bit different. It took me years to get it prepped and ready. At the time, I was working full-time and I did that on my days off.”

By looking an opening on the skull called the supratemporal fenestra, the snout and the shape of the bones at the back of the head, the team compared it to other phytosaurs and determined they’d discovered a separate species.

While West Texas is dry and dusty today, Mueller said the landscape looked more like a swampy, tropical rainforest during the Triassic period. Our planet’s landmasses had converged to form the supercontinent of Pangaea. In the forest undergrowth covered by tall conifers and choked with ferns, phytosaurs lurked beneath the water and waited for prey.

“A phytosaur resembles a crocodile,” Mueller said. “They had basically the same lifestyle as the modern crocodile by living in and around the water, eating fish, and whatever animals came to the margins of the rivers and lakes. But one of the big differences is the external nares, the nose, is back up next to its eyes instead of at the end of its snout.”

Mueller said scientists can tell the sexes of the animals by a distinctive feature on males. A bony crest stretched from the nostrils by the eyes to the tip of the animal’s beak – a feature lady phytosaurs probably found sexy.

Judging by the female’s skull size, which is more than three feet in length, Mueller guessed she would have measured 16 to 17 feet in length from nose to tail tip. The male would have measured about 17 to 18 feet. Their thin jaws suggested they hunted mainly fish as opposed to big prey.

Mueller said phytosaurs lived throughout the Triassic period from 230 to 203 million years ago, but died out during a mysterious mass extinction. Highly successful animals, they are commonly found because these animals liked to live in swampy areas and were more likely to become covered in sediment and fossilized.

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