FOSSILS/DINOS
BY ARISTOS GEORGIOU
ON 6/13/23
Agiant ancient lizard covered in thick armor and spikes has been discovered by scientists in Australia.
The turtle-like creature is "one of the most bizarre lizards found in recent times," said the authors of a study published in the journal Proceedings of the Royal Society B.
The now-extinct species, which forms part of the skink family, lived in the Pleistocene, the geological epoch that lasted from around 2.58 million to 11,700 years ago.
Skinks, a group of lizards that are found all over the world, are commonly recognized for their shiny, overlapping scales. There are more than 1,700 known species of skink today.
Agiant ancient lizard covered in thick armor and spikes has been discovered by scientists in Australia.
The turtle-like creature is "one of the most bizarre lizards found in recent times," said the authors of a study published in the journal Proceedings of the Royal Society B.
The now-extinct species, which forms part of the skink family, lived in the Pleistocene, the geological epoch that lasted from around 2.58 million to 11,700 years ago.
Skinks, a group of lizards that are found all over the world, are commonly recognized for their shiny, overlapping scales. There are more than 1,700 known species of skink today.
An artist's reconstruction shows a pair of Tiliqua frangens, with a small garden skink measuring 4 inches long in the corner for scale. The new species is by far the largest skink recorded to date.
KATRINA KENNY
Most skinks weigh less than 2 grams (0.07 ounces) and measure less than 10 centimeters (3.9 inches) in length.
But the newly discovered species is by far the largest skink recorded to date. In fact, it would have been more than a thousand times heavier than a typical skink, weighing roughly 2.4 kilograms, or 5.2 pounds, the researchers said.
The "gigantic" skink was at least 60 centimeters (2 feet) in length, whereas the longest living skinks today reach only around 35 centimeters (1.1 feet) when measuring between the nose and the vent at the start of the tail.
Most skinks weigh less than 2 grams (0.07 ounces) and measure less than 10 centimeters (3.9 inches) in length.
But the newly discovered species is by far the largest skink recorded to date. In fact, it would have been more than a thousand times heavier than a typical skink, weighing roughly 2.4 kilograms, or 5.2 pounds, the researchers said.
The "gigantic" skink was at least 60 centimeters (2 feet) in length, whereas the longest living skinks today reach only around 35 centimeters (1.1 feet) when measuring between the nose and the vent at the start of the tail.
The new species, named Tiliqua frangens, most closely resembles Australia's shingleback lizards, a species of blue-tongued skink. But T. frangens was more than twice as long and heavy as any of the largest living skinks today.
"The body size is huge compared to any other skink that we've ever known," Kailah Thorn, an author of the study who is affiliated with the Western Australian Museum, told Newsweek.
The fossils documented in the study show that the wide, heavy-set body of this creature was completely covered in "extremely thick, spikey armor," the authors said.
"The fossils preserve bones from within [the animal's] scales that acted as an external armor plating, and these bones have spikes on them," Thorn said.
She continued: "With the heavy armor plating, it's most likely that they foraged for plants out in the open during the day, much like living shingleback lizards in Australia and terrestrial tortoises in Africa and North America now. We can tell from the short and stocky limb bones that they moved slowly and had less maneuverability."
Compared with other groups, the fossil record of lizards and snakes has been poorly documented, even though there are more species of these animals than any other order of land vertebrates.
The identification of T. frangens as a new species, by contrast, was based on the fossils of many individuals, spanning babies to adults. As a result, the study's authors have been able to learn a lot about the creature's growth and development, ecology and evolutionary relationships.
The species had been described on two separate previous occasions as two different species. Each of those descriptions was based on a single bone, and the scientists involved could not match them to the one animal. So it was named twice—Aethesia frangens and Tiliqua laticephala.
But beginning in 2016, excavations conducted by the study's authors at the Wellington Caves in New South Wales, Australia—as well as investigations of museum collections—unearthed new fossil materials that enabled the team to re-describe T. frangens as a single new species.
"Now that we have so many more pieces, we know that they all fit together and represent one very unique animal," Thorn said.
The researchers found multiple pieces of this giant skink during the cave excavations. They also uncovered fossils belonging to the same species that were already stored in various museum collections but had not been described until now.
"The fossils are different pieces of the lizard's skeleton," Thorn said. "A lizard skull naturally breaks into multiple pieces, which makes them very difficult to reconstruct. All the material recovered from the new dig, as well as what I managed to find from the Queensland Museum, Australian Museum and Melbourne Museum paleontology collections, together represent most of the skull and some of the limbs and body of this species."
Given the number of different bones that the researchers found, the study's authors said that T. frangens is now the most completely known Australian fossil lizard.
"We can now recognize more parts of this animal than any other Australian fossil lizard," Thorn said.
The researchers have most of the head, the humerus (upper arm), the tibia (lower leg) and a few important back bones (from the neck and between the hips), she said, as well as chunks of the armor plating preserved.
"We also have bones from young individuals, so we can see how big these animals were when they were born—blue-tongues give birth to live young, they don't lay eggs—and how they changed shape as they grew," Thorn said.
The oldest T. frangens fossils that the researchers documented could be up to 2 million years old, she said. The youngest ones, meanwhile, have been dated to around 47,000 years before the present.
"This animal went extinct at the same time, and possibly for similar reasons, as the other Australian Pleistocene megafauna," Thorn said.
Looking at the palaeoclimate record, as well as examining other well-known fossil species from the same excavations, can yield information about the area in which these animals were living, according to Thorn.
"These lizards most likely lived in a temperate open woodland with patches of bluebush and saltbush plants—similar to modern shingleback habitat," she said.
The new findings highlight the fascinating ancient megafauna that once called this part of southeastern Australia home.
"Wellington Caves was the first site that Europeans uncovered megafauna fossils over 100 years ago, and we are still finding new giant fossil species there now," Thorn said. "There are other giant skink fossils in Australia, but we know very little about them because very few people work on fossil lizards here."
Small-Headed, Long-Necked Dinosaur That Weighs Same as Humans Discovered
ON 6/13/23 AT 7:01 PM EDT
A new species of long-necked dinosaur has been discovered, and researchers say it is among the smallest known members of a family of giants.
When scientists analyzed a fossil limb bone found in South Africa, they determined that it represented a mature, previously unknown sauropod that lived around 200 million years ago.
The sauropod group of dinosaurs includes the largest land-dwelling animals ever to walk the Earth, with some species estimated to have weighed more than 90 metric tons. But in contrast to these giants, the new sauropod described in the study is thought to have had a body mass of only around 75 kilograms (165 pounds)—about the same as some humans—according to a study published Tuesday in the journal Royal Society Open Science.
A new species of long-necked dinosaur has been discovered, and researchers say it is among the smallest known members of a family of giants.
When scientists analyzed a fossil limb bone found in South Africa, they determined that it represented a mature, previously unknown sauropod that lived around 200 million years ago.
The sauropod group of dinosaurs includes the largest land-dwelling animals ever to walk the Earth, with some species estimated to have weighed more than 90 metric tons. But in contrast to these giants, the new sauropod described in the study is thought to have had a body mass of only around 75 kilograms (165 pounds)—about the same as some humans—according to a study published Tuesday in the journal Royal Society Open Science.
The new sauropod's limb bone is shown, along with a cross section as seen under a microscope. The dinosaur is the smallest known sauropod from the Jurassic Period, according to researchers.
CHAPELLE ET AL./ROYAL SOCIETY OPEN SCIENCE
This places it among the smallest known sauropodomorphs—the group that contains sauropods and their ancestors—ever to roam our planet. It is also the smallest sauropod ever reported from the Jurassic—the geologic period extending from around 201 million to 145 million years ago.
"Up until now, we knew that sauropodomorphs appeared in the Triassic, some 233 million years ago. At that time, they were very small, about 10 kilograms [22 pounds]," Kimberley Chapelle, an author of the study, told Newsweek. "But as soon as we get to the Jurassic, they already weigh several hundred kilograms and keep increasing in size until they reached multiple [metric tons].
"That's what sauropods are known for, being the largest land animals to ever roam the Earth," said Chapelle, who is affiliated with the American Museum of Natural History. "But now we know that there were still some small ones in the Jurassic. This is the first sauropodomorph under 100 kilograms in the entire Jurassic."
The latest discovery helps scientists to better understand the ecosystems at the time, as well as the evolution of this group of dinosaurs, according to Chapelle.
This places it among the smallest known sauropodomorphs—the group that contains sauropods and their ancestors—ever to roam our planet. It is also the smallest sauropod ever reported from the Jurassic—the geologic period extending from around 201 million to 145 million years ago.
"Up until now, we knew that sauropodomorphs appeared in the Triassic, some 233 million years ago. At that time, they were very small, about 10 kilograms [22 pounds]," Kimberley Chapelle, an author of the study, told Newsweek. "But as soon as we get to the Jurassic, they already weigh several hundred kilograms and keep increasing in size until they reached multiple [metric tons].
"That's what sauropods are known for, being the largest land animals to ever roam the Earth," said Chapelle, who is affiliated with the American Museum of Natural History. "But now we know that there were still some small ones in the Jurassic. This is the first sauropodomorph under 100 kilograms in the entire Jurassic."
The latest discovery helps scientists to better understand the ecosystems at the time, as well as the evolution of this group of dinosaurs, according to Chapelle.
The new dinosaur was a plant eater that walked on two legs. It also had a long neck and a small head.
"The most surprising thing about the dinosaur is that it is really small—approximately 75 kilograms [165 pounds], which is about as heavy as an impala," Chapelle said. "We also know for a fact that it is an adult and wouldn't grow much bigger."
To place the new dinosaur's size into context, the Jurassic sauropodomorph that is the next step up in size is already 50 percent bigger. And most of the sauropodomorph dinosaurs from the time had a body mass of several hundred pounds.
The area in which the dinosaur once lived would have been a warmer environment than today, with fewer plants and braided rivers running through the landscape, according to Chapelle.
A diagram shows the smallest adult Jurassic sauropodomorph in orange, compared with other relatives in the group and a human. The orange sauropod is thought to have weighed around 165 pounds.
MODIFIED FROM SCOTT HARTMAN AND ANDREW KNIGHT UNDER CC BY 3.0 LICENSE
The fossil limb bone that the study is based on was originally found by James Kitching in 1978 in the eastern part of South Africa's Free State province. Since then, the fossil has been kept at the Evolutionary Studies Institute at Johannesburg's Wits University.
Initially, the fossil was thought to represent Massospondylus—Southern Africa's most abundant dinosaur. But it was never really examined on its own until the latest study, which found that it represented a new species—an early ancestor of well-known giants like Diplodocus.
Because the study's authors were able to examine only this one fossil bone for their research, they have not yet named the new species.
"There may be a more complete fossil of it in a museum somewhere or in the field that will allow us to learn more about it and name it," Chapelle said.
"Now that we know it exists, we can go back and look at collections in museums, and there may be another one hiding in there. We also still excavate dinosaurs every year, so we may find one," she said.
The fossil limb bone that the study is based on was originally found by James Kitching in 1978 in the eastern part of South Africa's Free State province. Since then, the fossil has been kept at the Evolutionary Studies Institute at Johannesburg's Wits University.
Initially, the fossil was thought to represent Massospondylus—Southern Africa's most abundant dinosaur. But it was never really examined on its own until the latest study, which found that it represented a new species—an early ancestor of well-known giants like Diplodocus.
Because the study's authors were able to examine only this one fossil bone for their research, they have not yet named the new species.
"There may be a more complete fossil of it in a museum somewhere or in the field that will allow us to learn more about it and name it," Chapelle said.
"Now that we know it exists, we can go back and look at collections in museums, and there may be another one hiding in there. We also still excavate dinosaurs every year, so we may find one," she said.
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