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Siberian mammoth molars yield oldest DNA ever recovered – CBC.ca

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Scientists say they have recovered the oldest DNA on record, extracting it from the molars of mammoths that roamed northeastern Siberia up to 1.2 million years ago in research that broadens the horizons for understanding extinct species.
 
The researchers said on Wednesday they had recovered and sequenced DNA from the remains of three individual mammoths in Russia’s extreme north.

The animals — elephant cousins that were among the large mammals that dominated ice age landscapes — had been entombed in permafrost conditions that helped preserve the ancient genetic material. While the remains were first discovered in the 1970s, new scientific methods were needed to extract the DNA.

The oldest of the three mammoths, discovered near the Krestovka river, was approximately 1.2 million years old. Another, from near the Adycha river, was about 1 million to 1.2 million years old. The third, from near the Chukochya river, was roughly 700,000 years old.

‘Oldest DNA ever recovered’

“This is by a wide margin the oldest DNA ever recovered,” said evolutionary geneticist Love Dalén of the Centre for Palaeogenetics in Sweden, who led the research published in the journal Nature.
 
Until this most recent discovery, the oldest DNA came from a horse that lived in Canada’s Yukon territory about 700,000 years ago. In comparison, the human species, Homo sapiens, first appeared roughly 300,000 years ago.


 
“This DNA was extremely degraded into very small pieces, and so we had to sequence many billions of ultra-short DNA sequences in order to puzzle these genomes together,” Dalén said.

Most knowledge about prehistoric creatures comes from studying skeletal fossils, but there is a limit to what these can tell about an organism, particularly when it comes to genetic relationships and traits.

Ancient DNA can help fill in the blanks but it’s highly perishable. Sophisticated new research techniques are enabling scientists to recover ever-older DNA — a maximum of two to three million years old, Dalén said.

That could shed light on some bygone species, but it would leave many others unattainable — including the dinosaurs, which went extinct 66 million years ago.

According to Dalén, when DNA can be looked at on a million-year time scale, it allows scientists to study the process of speciation, or the formation of new species, in a much more detailed way.

“Morphological analysis on bones usually only allow researchers to study a handful of characteristics in the fossils, whereas with genomics we are analyzing many tens of thousands of characteristics,” he said.

Insights into evolution, migration

The researchers gained insights into mammoth evolution and migration by comparing the DNA to that of mammoths that lived more recently. The last mammoths disappeared roughly 4,000 years ago.

The oldest of the three specimens, the Krestovka mammoth, belonged to a previously unknown genetic lineage that diverged from the lineage leading to the well-known wooly mammoth more than two million years ago.

Geneticist Tom van der Valk of SciLifeLab in Sweden, the study’s first author, said it appears that members of the Krestovka lineage were the first mammoths to migrate from Siberia into North America over a now-disappeared land bridge about 1.5 million years ago, with wooly mammoths migrating about 400,000 to 500,000 years ago.

The Adycha mammoth’s lineage apparently was ancestral to the wooly mammoth, researchers found, and the Chukochya individual is one of the oldest-known wooly mammoth specimens.

DNA analysis showed that genetic variants associated with enduring frigid climes such as hair growth, thermoregulation, fat deposits, cold tolerance and circadian rhythms were present long before the origin of the wooly mammoth.

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Some Of This Year's Official Hurricane Names Are Inspired By Frozen Characters – 915thebeat.com

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The official start date of hurricane season is three months away as meteorologists expect a particularly active period this year when three of the anticipated massive storms will be named after Disney characters.  The World Meteorological Organization’s list of names for hurricanes in both the Atlantic and Pacific basins includes Olaf, Elsa, and Ana – three characters from Frozen.  The film was released in 2013, and the characters’ names were initially placed on the list of hurricane names by the WMO in 2015.  This year, the WMO and National Hurricane Center is recycling the list from 2015, as is custom every six years.  Names of hurricanes that are unusually destructive are retired and never to be used again.

For Hurricane name information, visit: NOAA (You will be redirected)

© 2021 Corus Radio, a division of Corus Entertainment Inc.

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This Tourism Ad for Mars Wraps With a Bleak Jolt of Reality – Muse by Clio

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Created by Fred & Farid Los Angeles, the ad begins with an aspirational voiceover: “After more than 5 million years of human existence on Earth, it’s time for a change. Mars: 56 million square miles of untouched land, breathtaking landscapes and incredible views.” You have to look at it from a certain angle—the opposite of Elon’s, really—to feel the irony in its premise. 

It ends with a forbidding statement: “And for the 99 percent who will stay on Earth … we’d better fix climate change.”

Ah, the catch: All these promises of adventure, and escape from our existential woes, will likely be reserved for the few who can afford it. (Unless you’re into the whole indentured servitude thing … and hey, if you’ve still got school loans, what’s a couple million more before you die?)

“We wanted to highlight pure nonsense,” said Fridays for Future. “Government-funded space programs and the world’s ultra-wealthy 1 percent are laser focused on Mars … and yet most humans will never get a chance to visit or live on Mars. This is not due to a lack of resources, but the fact that our global systems don’t care about us and refuse to take equitable action.”

To drive that point home, the organization points out that NASA’s Perseverance Rover cost $2.7 billion for development, launch, operations and analysis. While we’re hard-pressed to begrudge NASA a budget at the worst of times, it’s hard to look at that figure and think about the fact that we still haven’t figured out recycling.

The ad went live on Feb. 18, the day Perseverance landed on Mars. Contrast this date with another one, just a smidge down the road: Elon Musk is “highly confident” that SpaceX will get people there by 2026. (Though if that projection is anything like his Tesla ones, feel free to add 5-10 years to that with confidence.)

This marks Fred & Farid LA’s third collaboration with Fridays For Future. It follows “House on Fire” and “If You Don’t Believe in Global Warming, How About Local Warming?” The hope, in this case, is that some bleak sci-fi will finally be what motivates people to action.

Tell that to Greta Thunberg.

On the other hand, if you’d like some actual sci-fi with a spin on what happens to everybody on Earth when all the Well-Heeled People leave, we recommend N.K. Jemisin’s Emergency Skin. (Bonus points: Buy it at a Black-owned bookstore. Thanks to Oprah, you can find one by state.) It’s short and surprisingly optimistic—so optimistic that we actually worry the most exploitative wealthyfolk will instead choose to stay, which in our minds seems increasingly likely. 

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More images of Mars, Perseverance rover's exciting work to happen in coming weeks: NASA's Indo-American engineer – EdexLive

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Vishnu Sridhar, a 27-year-old Indian-American lead system engineer with NASA’s Perseverance rover, has said that the most exciting work on the awe-inspiring Mars mission will happen in the coming weeks.

Sridhar, who is from Queens, New York, is a lead system engineer at NASA’s Jet Propulsion Laboratory (JPL) in Pasadena, California for SuperCam on the Mars 2020 Perseverance rover, which is on a mission to search for signs of past life on the Red Planet.

He said some of the rover’s most exciting work will be done in the coming weeks.

“We’re going to be taking more images of Mars, we’re going to be shooting lasers with the SuperCam instrument, we’re going to be recording audio with our microphone, and eventually, soon in near future, we are going to deploy our helicopter, and do the first powered flight on Mars,” Sridhar told ABC7 channel.

SuperCam is a remote-sensing instrument that will use laser spectroscopy to analyse the chemical composition of rocks on the Martian surface.

It analyses terrain that the rover cannot reach. It is an instrument designed to scan rocks and minerals—from up to 20 feet away—to determine their chemical makeup. The Perseverance rover was launched on July 30 last year and successfully landed on Mars on February 18 this year.

The rover, the SuperCam, and its other devices together will help scientists search for clues of past life on Mars. Its predecessor Curiosity is still functioning eight years after landing on Mars.

The two-year Perseverance mission is NASA’s latest and most advanced mission to find evidence of past life on Mars.

Sridhar said it was important that the mission was happening despite the ongoing COVID-19 pandemic.

“NASA missions are clearly trying to explore and answer the basic question.

Perseverance is also trying to seek that, and eventually answer the question that was there life on Mars, was there life outside Earth, and it was definitely a tough period for us during COVID-19 and for everyone else around the globe,” he said.

“And that’s why I love the name of Perseverance because we persevered through the pandemic and there was a paradigm shift, we learned a lot about how to do engineering remotely.

And we went through all that we learned and now we are successful on Mars and it’s a great achievement for humankind,” he said.

Sridhar’s time at JPL over the past five years has been dedicated to Mars and is currently the instrument engineer for SuperCam on the Mars 2020 Rover.

“Summer 2019 was when instruments came in from France and Los Alamos and when we physically integrated SuperCam with the Perseverance rover.

That’s something I will cherish for the rest of my life, to have touched and worked on a piece of hardware that’s on its way to Mars,” he reminisced.

The US space agency on Monday released the first audio from Mars, a faint recording of a gust of wind captured by the Perseverance rover.

Perseverance will attempt to collect 30 rock and soil samples in sealed tubes to be sent back to Earth sometime in the 2030s for lab analysis.

The rover is only the fifth to set its wheels down on Mars.

The feat was first accomplished in 1997, and all of them have been American.

The US is aiming for an eventual human mission to the planet, though planning remains preliminary.

Sridhar attended Aviation High School in Queens and grew up in Rego Park.

He graduated in Aerospace Engineering from Georgia Tech and has always been fascinated by flight and space exploration.

“One of the key events that sparked my interest in space and exploration was watching National Geographic.

The Carl Sagan TV show Cosmos,” he said.

According to his NASA profile page, while in elementary school he wanted to become a National Geographic photographer and travel the world.

Indian-American woman scientist Swati Mohan had also played a key role in NASA Mars rover landing.

Mohan, who leads the guidance, navigation, and control operations of NASA’s Mars 2020 mission, was the first to confirm that the rover had successfully touched down on the Martian surface.

“Touchdown confirmed! Perseverance safely on the surface of Mars, ready to begin seeking signs of past life,” Mohan announced, prompting her colleagues at NASA to fist-bump and break into celebrations.

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