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Rare ancient baby turtle identified inside fossil egg – CBC.ca

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A fossil egg found by a Chinese farmer has turned out to have a rare surprise inside: A baby turtle nearly ready to hatch. And that’s allowed scientists to make a unique and important connection, a new study reports.

“This is actually the first time that [fossil] turtle eggs or a nest really could be attributed to a particular turtle,” said Darla Zelenitsky, a co-author of the study and an associate professor of paleontology at the University of Calgary.

The egg belonged to a nanhsiungchelyid turtle, an ancient, huge, land-dwelling creature that lived in Asia and North America and was related to modern softshell turtles, according to the study published Wednesday in the journal Proceedings of the Royal Society B.

The turtle lived among dinosaurs — such as long-necked, plant-eating sauropods, duck-billed hadrosaurs and large meat eaters, similar to tyrannosaurs — during the Cretaceous period. It went extinct with them.

“It was a giant turtle for the time,” said Zelenitsky. 

She estimates the female that laid the egg was more than 1.6 metres long — roughly as long as an average woman is tall, and longer than a giant Galapagos tortoise, although it had a flatter, less domed shell.

A baby nanhsiungchelyid turtle, which lived during the age of dinosaurs, hatches from its egg in this artist’s impression. (Masato Hattori)

Like the Galapagos tortoise, it lived entirely on land. Nanhsiungchelyids lived in arid desert environments, but the egg was found near the shores of an ancient river.

“During the rainy season, these river systems may have overflowed and buried the eggs that were on the floodplain, potentially preserving them as fossils,” said Zelenitsky. 

The Henan region of China where it was found is also known for fossil dinosaur eggs, she said.

The fossil egg was found in 2018 by a farmer in China’s Henan province. (Yuzheng Ke)

The estimated size of the embryo’s mother is based on the known relationship between the size of a turtle’s body and its eggs. The fossil is roughly the size and shape of a tennis ball — perfectly spherical — with a shell as thick as that of a much bigger ostrich egg.

“I was thinking, ‘How did this little turtle hatch out of this egg, with it being so thick?'” Zelenitsky recalled. “They must have been doing a lot of flexing and extending … to work their way out.” 

The embryo was extremely well preserved, allowing researchers to X-ray it with a CT scanner and reconstruct its skeleton in 3D. They concluded it was a nanhsiungchelyid after comparing it to other ancient and modern turtles.

Egg helps identify nests

By identifying that egg, which was found by itself, the researchers were also able to identify entire nests of identical turtle eggs found elsewhere. It showed that nanhsiungchelyids normally laid 15 to 30 eggs at a time.

This artist’s impression shows baby nanhsiungchelyid turtles hatching from their eggs. The fossil with the embryo allowed researchers to identify identical eggs in other nests, showing that they typically were laid in clutches of 15 to 30. (Masato Hattori)

The farmer who originally found the egg in 2018 donated it to a museum.

The lead author of the study, Yuzheng Ke, a graduate student at the China University of Geosciences in Wuhan, contacted Zelenitsky and asked her to participate because she previously had done research on dinosaur eggs and even a pregnant turtle.

Zelenitsky said she jumped at the chance: “I was excited about it the entire time.”

The study was funded by the National Natural Science Foundation of China and the Natural Sciences and Engineering Research Council of Canada.

Daniel Lawver, a researcher at Stony Brook University’s School of Medicine in New York who was not involved in the study, has been doing similar, not-yet-published research on a different turtle egg and embryo.

He was pleasantly surprised by the study, he said, as a turtle with an identifiable embryo inside is a “very, very rare” find and this one is a “really cool specimen.”

That’s because most turtles have thin eggshells composed of a mineral called aragonite that’s unstable on the Earth’s surface. During fossilization, it’s converted to another mineral that makes them hard to identify, Lawver said. And often, they’re fossilized before the embryo has developed, resulting in a fossil eggshell filled with rock. 

This is the fossil of an adult nanhsiungchelyid turtle from Alberta. Adult nanhsiungchelyid were very large. The one that laid the egg was estimated to be 1.6 metres long. (Royal Tyrell Museum)

Jordan Mallon, a paleontologist at the Canadian Museum of Nature in Ottawa who has studied nanhsiungchelyid fossils from North America, including Alberta, agrees with the identification of the embryo. He was also not involved with this research.

The thick, water-retaining eggshells add to evidence that the turtles were fully land-dwelling, he said, something that has been debated.

The techniques used in the study could later be used to examine older turtle embryos and uncover long-standing puzzles about turtle evolution, like how their shells evolved, said Mallon.

“I think the authors of this paper are sort of leading the way.”

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This Canadian 'Dark Sky Highway' is a stargazer dream – The Weather Network

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E.C. Manning Provincial Park is one of the most popular provincial parks in British Columbia.

Located in the heart of the Cascade Mountains, its climate and geography have combined to make this park a go-to destination for stargazers across the country.

The park is within a three-hour drive from either the Lower Mainland or the Okanagan, with the closest city being about 45 minutes away. Road trippers can get there using BC Highway 3, also known as the Crowsnest Highway, located along what has become known as the Dark Sky Highway, due to the limited light pollution.


Photo of the night sky captured along B.C.’s Dark Sky Highway. The five bright stars stretched out through the right-hand side of the image are part of the constellation Ursa Major, aka the Big Dipper. (Mia Gordon)

Every year, photographers from around the country come out here to get a good glimpse of the Milky Way and other incredible constellations, and now the Manning Resort and the park are working towards becoming a dark sky designation.

“That means it is a continued commitment to preserve and protect the night and the environment but more specifically the organisms that live in the park that rely on the night to hunt and navigate,” explained Manning Park Communications Manager Emma Schram.

Every year, the resort partners with the Royal Astronomical Society of Canada for an Astronomy Weekend, where visitors can speak with experts, learn how to use a telescope, and even participate in yoga under the stars. This year’s event is taking place October 15-17, and while it is sold out, any time of year is the perfect time to go stargazing in the park.

Learn more about this stargazer’s dream destination in the video above.


Thumbnail image courtesy: Getty Images

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Faces of 3 Egyptian mummies revealed for the first time – Editorials 99

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New DNA sequencing technology is giving us a first glimpse at what ancient men looked like — before they were mummies.

Genetic researchers have revealed highly detailed three-dimensional renderings of the faces of three Egyptian men who lived more than 2,000 years ago, using DNA pulled from their mummified remains.

The digital reconstructions show the men at age 25, who were unearthed in the vicinity of the ancient Egyptian city of Abusir el-Meleq, in the south of Cairo. Scientists estimate the men were each buried sometime between 1380 B.C. and A.D. 425, Live Science has reported. Their DNA was previously sequenced in 2017 at the Max Planck institute in Germany — at the time, the first successful reconstruction of an Egyptian mummy’s genome in history.

Since then, researchers at Parabon NanoLabs in Reston, Virginia have used forensic DNA phenotyping to create 3D models of the men’s faces, a process by which genetic data is used to predict facial features and other physical characteristics of the sampled mummy.

“This is the first time comprehensive DNA phenotyping has been performed on human DNA of this age,” Parabon said in a statement

The technology is already being used to solve modern cold cases involving unidentified victims.
Parabon NanoLabs

The lab used a combination of efforts to reconstruct the faces. Some features, including skin and eye color, can be predicted via genetic markers in the individual’s genome, while others are measured through what’s left of their physical remains.

Parabon’s methods revealed that the men had light brown skin with dark eyes and hair, and that the men were more genetically similar to modern-day Mediterranean populations than that of Egypt today.

Their process had to account for the fact that human DNA degrades over time, and is likely to be contaminated by bacterial DNA. In this case, researchers use genetic commonalities between human populations to fill in the gaps of their mummy genome.

Researchers see that this process could eventually be used in contemporary forensics, in order to identify more recent remains of unknown individuals.

Parabon’s work in genetics has already been used to crack 175 cold cases, including nine solved using the methods described in the current study, they told Live Science.

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Some animal species can survive successfully without sexual reproduction: study – CTV News

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TORONTO —
An international team of researchers have found that some animals can survive over very long periods of time — possibly millions of years — without sexual reproduction.

By studying a tiny beetle mite species, just one-fifth of a millimetre in size, scientists found that asexual reproduction can be successful in the long term.

The study authors note that until now, the survival of an animal species over a geologically long period of time without sexual reproduction was considered very unlikely, if not impossible.

Asexual reproduction involves one parent and produces offspring that are genetically identical to each other and the parent, while sexual reproduction involves two parents and produces offspring that are genetically unique.

Using the Oppiella nova beetle mite, an all-female species, researchers from the Universities of Cologne and Göttingen, the University in Lausanne in Switzerland and the University of Montpellier in France, demonstrated for the first time the so-called Meselson effect in animals.

According to the study, the Meselson effect is a characteristic trace in the genome of an organism that suggests “purely asexual reproduction.”

In the study, researchers looked at different populations of the Oppiella nova and the closely related, but sexually reproducing species, Oppiella subpectinata in Germany and sequenced their genomes. The study found that the sequencing of the Oppiella nova genomes showed the Meselson effect.

The findings were published Tuesday in peer-reviewed scientific journal PNAS.

Scientists had previously considered the Oppiella nova species an “ancient asexual scandal” as they couldn’t determine how the beetles were managing to reproduce without having sexual intercourse.

Initially, the study notes that biologists thought these beetles were hiding their acts of reproduction.

“There could be, for example, some kind of ‘cryptic’ sexual exchange that is not known. Or not yet known,” first author of the study Alexander Brandt of the University of Lausanne said in a press release.

“For example, very rarely a reproductive male could be produced after all — possibly even ‘by accident’,” he added.

However, the Oppiella nova beetle mite clones itself rather than reproducing, according to the study.

Researchers say the existence of ancient asexual animal species can be difficult to explain as asexual reproduction can seem “very disadvantageous” in the long term due to a lack of genetic diversity.

Biologists say there is typically an “evolutionary advantage” to having two different genomes that only a pair of parents can supply. Through sexual reproduction, this ensures a “constant ‘mixing’ of the two copies” of the genome in each of their cells.

This means that the two sets of genetic information remain very similar, but there are differences that allow organisms on earth to adapt over time, evolving characteristics that best suit the changing environment.

Researchers also found that it is possible for asexually reproducing species to introduce genetic variance into their genomes and thus adapt to their environment during evolution, despite producing genetic clones of themselves.

Scientists say that lack of “genome mixing” compared to sexual species causes the two genome copies of asexual animals to accumulate separate mutations and evolve independently over time.

While the survival rate of a species without sexual reproduction is quite rare, scientists conclude that it is not impossible.

“Our results clearly show that O. nova reproduces exclusively asexually. When it comes to understanding how evolution works without sex, these beetle mites could still provide a surprise or two,” Jens Bast, junior research group leader at the University of Cologne, said in the press release.

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