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7 billion-year-old stardust inside meteorite oldest solid material ever found on Earth – Daily Sabah

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Researchers said Monday that new techniques have allowed them to identify the oldest solid material ever found on earth.

The stardust, formed 5 to 7 billion years ago, came from a meteorite that fell to Earth 50 years ago in Australia, they said in a paper published in the journal PNAS.

It came down in 1969 in Murchison, Victoria state, and scientists from Chicago’s Field Museum have possessed a piece of it for five decades.

Philipp Heck, curator of meteorites at the museum, examined pre-solar grains, which are bits of stardust that become trapped in meteorites, making them time capsules of the period before the sun was born.

“They’re solid samples of stars, real stardust,” Heck said in a statement.

When the first stars died after 2 billion years of life, they left behind the stardust, which formed into the block which fell to earth as the meteorite in Australia.

Although researchers first identified the grains in 1987, their age could not be determined.

But Heck and other colleagues recently used a new method to date these grains, which are microscopic in size. They are from silicon carbide, the first mineral formed when a star cools.

To separate the ancient grains from the relatively younger ones, scientists crushed fragments of the meteorite into a powder. Then they dissolved it in acid, which left only the pre-solar particles.

“It’s like burning down the haystack to find the needle,” Heck said.

When dust is in space, it is exposed to cosmic rays which slowly change its composition. This allows researchers to date it.

A decade ago, only 20 grains from the meteorite were dated by a different method. Now, researchers have been able to determine the age of 40 grains, most of which are between 4.6 billion and 4.9 billion years old.

These ages correspond to the moment when the first stars began to break up, and since that type of star lived for 2 to 2.5 billion years, the stardust can be as old as 7 billion years.

“These are the oldest solid materials ever found, and they tell us about how stars formed in our galaxy,” Heck said.

The new dating by this team confirms an astronomical theory which predicted a baby boom of stars before the formation of our sun, instead of a constant rhythm of star formation.

“We basically came to the conclusion that there must have been a time in our galaxy when more stars formed than normal, and at the end of their lives they become dust producing,” Heck told AFP.

The task now is to apply the same method on other meteorites.

But according to Heck, there are fewer than five known to be in collections and big enough to give up such secrets.

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Ice age bird found frozen in Siberia dates back 46,000 years – The Loop

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Scientists studying the remarkably well-preserved remains of an Ice Age bird have identified the specimen as a horned lark.

Buried and frozen in permafrost near the village of Belaya Gora in north-eastern Siberia, the bird was discovered by local fossil ivory hunters, who passed it on to a team of experts, including Nicolas Dussex and Love Dalén from the Swedish Museum of Natural History, for testing.

Radiocarbon dating revealed the bird lived around 46,000 years ago, and genetic analysis identified it as a horned lark (Eremophila alpestris), according to a paper published Friday in the journal Communications Biology.

Dalén told CNN that research showed the bird may be an ancestor to two subspecies of lark alive today, one in northern Russia and the other on the Mongolian steppe.

“This finding implies that the climatic changes that took place at the end of the last Ice Age led to formation of new subspecies,” he said.

The preservation of the bird is explained in large part by the cold of the permafrost, explained Dussex, but this specimen is in extraordinarily good condition.

“The fact that such a small and fragile specimen was near intact also suggests that dirt/mud must have been deposited gradually, or at least that the ground was relatively stable so that the bird’s carcass was preserved in a state very close to its time of death,” said Dussex.

The next stage of research involves sequencing the bird’s entire genome, said Dalén, which will reveal more about its relationship to present day subspecies and estimate the rate of evolutionary change in larks.

Scientists working in the area have also found carcasses and body parts from other animals such as wolves, mammoths and wooly rhinos.

Dussex described such findings as “priceless” as they allow researchers to retrieve DNA and sometimes RNA, a nucleic acid present in all living cells.

“This in turn will open new opportunities to study the evolution of ice age fauna and understand their responses to climate change over the past 50-10 thousands of years ago,” added Dussex.

The horned lark was discovered at the same site as an 18,000-year-old frozen puppy, which Dalén and Dussex are also studying.

Using carbon dating on the creature’s rib bone, experts were able to confirm that the specimen had been frozen for around 18,000 years, but extensive DNA tests have so far been unable to show whether the animal was a dog or a wolf.

Scientists can normally tell the difference relatively easy, and researchers hope that further tests on the remains will provide more insight into exactly when dogs were domesticated.

More on this story from CTVNews.ca

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Frozen bird turns out to be 46000-year-old horned lark – EurekAlert

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IMAGE: This is the 46,000-year-old horned lark found in Siberia.
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Credit: Love Dalén

Scientists have recovered DNA from a well-preserved horned lark found in Siberian permafrost. The results can contribute to explaining the evolution of sub species, as well as how the mammoth steppe transformed into tundra, forest and steppe biomes at the end of the last Ice Age.

In 2018, a well-preserved frozen bird was found in the ground in the Belaya Gora area of north-eastern Siberia. Researchers at the Centre for Palaeogenetics, a new research center at Stockholm University and the Swedish Museum of Natural History, haves studied the bird and the results are now published in the scientific journal Communications Biology. The analyses reveals that the bird is a 46 000-year-old female horned lark.

“Not only can we identify the bird as a horned lark. The genetic analysis also suggests that the bird belonged to a population that was a joint ancestor of two sub species of horned lark living today, one in Siberia, and one in the steppe in Mongolia. This helps us understand how the diversity of sub species evolves,” says Nicolas Dussex, researcher at the Department of Zoology at Stockholm University.

The result has significance on another level as well. During the last Ice Age, the mammoth steppe spread out over northern Europe and Asia. The steppe was home to now extinct species such as the woolly mammoth and the woolly rhinoceros. According to one theory, this ecosystem was a mosaic of habitats such as steppe, tundra and coniferous forest. At the end of the last Ice Age, the mammoth steppe was divided into the biotopes we know today – tundra in the north, taiga in the middle and steppe in the south.

“Our results support this theory since the diversification of the horned lark into these sub species seems to have happened about at the same time as the mammoth steppe disappeared,” says Love Dalén, Professor at the Swedish Museum of Natural History and research leader at the Centre for Palaeogenetics.

In the slightly longer term the researchers´ ambition is to map the complete genome of the 46 000-year-old lark and compare it with the genomes from all sub species of horned larks.

“The new laboratory facilities and the intellectual environment at the Centre for Palaeogenetics will definitely be helpful in these analyses,” says Love Dalén.

The researchers at the Centre for Palaeogenetics have access to plenty of samples from similar findings from the same site in Siberia, including the 18 000-year-old puppy called “Dogor” which the researchers are are studying to determine if it is a wolf or a dog. Other findings include the 50 000-year-old cave lion cub “Spartak” and a partially preserved woolly mammoth.

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Read the article in Communications Biology “Biomolecular analyses reveal the age, sex and species identity of a near-intact Pleistocene bird carcass” DOI 10.1038/s42003-020-0806-7

Visit the web site of the Centre for Palaeogenetics: palaeogenetics.com

Read more on the research at the new centre: Old genes in new centre https://www.su.se/english/research/research-news/old-genes-in-new-centre-1.484839

Contact

Love Dalén, Professor at the Swedish Museum of Natural History and research leader at the Centre for Palaeogenetics, love.dalen@nrm.se, phone: +46 (0)70 777 27 94

Nicolas Dussex, Researcher at the Department of Zoology, Stockholm University, and at the Centre for Palaeogenetics, nicolas.dussex@gmail.com, phone: +46 (0)70 031 70 26

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.

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Well-preserved frozen bird found in Siberia is 46,000 years old – Tech Explorist

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In 2018, a well-preserved frozen bird was found in the ground in the Belaya Gora area of north-eastern Siberia. Researchers at the Centre for Palaeogenetics, a new research center at Stockholm University and the Swedish Museum of Natural History, have studied the bird and found that the bird is a 46,000-year-old female horned lark.

Scientists recovered the DNA from the bird. The genetic analysis also suggests that the bird belonged to a population that was a joint ancestor of two sub species of horned lark living today, one in Siberia, and one in the steppe in Mongolia.

Nicolas Sussex, scientist at the Department of Zoology at Stockholm University, said, “The results can contribute to explaining the evolution of subspecies, as well as how the mammoth steppe transformed into the tundra, forest and steppe biomes at the end of the last Ice Age.”

“The study helps us understand how the diversity of subspecies evolves.”

The outcome has significance on another level too. During the last Ice Age, the mammoth steppe spread out over northern Europe and Asia. The steppe was home to now-extinct species, for example, the wooly mammoth and the wooly rhinoceros. As indicated by one hypothesis, this ecosystem was a mosaic of habitats, for example, steppe, tundra, and coniferous forest. Toward the finish of the last Ice Age, the mammoth steppe was divided into the biotopes we know today – tundra in the north, taiga in the middle, and steppe in the south.

Love Dalén, Professor at the Swedish Museum of Natural History, said, “Our results support this theory since the diversification of the horned lark into these sub species seems to have happened about at the same time as the mammoth steppe disappeared.”

In the future, scientists aim to map the complete genome of the 46,000-year-old lark and compare it with the genomes from all sub species of horned larks.

Love Dalén said, “The new laboratory facilities and the intellectual environment at the Centre for Palaeogenetics will be helpful in these analyses.”

The study is published in the journal Communications Biology.

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