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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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Russian actor, director arrive back on earth from ISS – Euronews

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A Soyuz space capsule carrying a cosmonaut and two Russian filmmakers has returned to Earth after leaving the International Space Station (ISS) earlier on Sunday.

The capsule landed on the steppes of Kazakhstan carrying Russian actor Yulia Peresild and film director Klim Shipenko, who returned to Earth after filming scenes for the world’s first movie in orbit – a project the Kremlin said would help burnish the nation’s space glory.

Peresild and Shipenko rocketed into orbit in a Russian Soyuz spacecraft on October 5 for a 12-day stint on the station to film segments of the movie titled “Challenge,” in which a surgeon played by Peresild rushes to the space station to save a crew member who needs an urgent operation in orbit.

The pair returned to Earth on Sunday with another Russian cosmonaut, Oleg Novitskiy, who also stars as the ailing cosmonaut in the movie.

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VIDEO: NASA’s asteroid hunter Lucy soars into sky with diamonds – Abbotsford News

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A NASA spacecraft named Lucy rocketed into the sky with diamonds Saturday morning on a 12-year quest to explore eight asteroids.

Seven of the mysterious space rocks are among swarms of asteroids sharing Jupiter’s orbit, thought to be the pristine leftovers of planetary formation.

An Atlas V rocket blasted off before dawn, sending Lucy on a roundabout journey spanning nearly 4 billion miles (6.3 billion kilometers). Researchers grew emotional describing the successful launch — lead scientist Hal Levison said it was like witnessing the birth of a child. “Go Lucy!” he urged.

Lucy is named after the 3.2 million-year-old skeletal remains of a human ancestor found in Ethiopia nearly a half-century ago. That discovery got its name from the 1967 Beatles song “Lucy in the Sky with Diamonds,” prompting NASA to send the spacecraft soaring with band members’ lyrics and other luminaries’ words of wisdom imprinted on a plaque. The spacecraft also carried a disc made of lab-grown diamonds for one of its science instruments.

In a prerecorded video for NASA, Beatles drummer Ringo Starr paid tribute to his late colleague John Lennon, credited for writing the song that inspired all this.

“I’m so excited — Lucy is going back in the sky with diamonds. Johnny will love that,” Starr said. “Anyway, if you meet anyone up there, Lucy, give them peace and love from me.”

The paleoanthropologist behind the fossil Lucy discovery, Donald Johanson, had goose bumps watching Lucy soar — “I will never look at Jupiter the same … absolutely mind-expanding.” He said he was filled with wonder about this “intersection of our past, our present and our future.”

“That a human ancestor who lived so long ago stimulated a mission which promises to add valuable information about the formation of our solar system is incredibly exciting,” said Johanson, of Arizona State University, who traveled to Cape Canaveral for his first rocket launch.

Lucy’s $981 million mission is the first to aim for Jupiter’s so-called Trojan entourage: thousands — if not millions — of asteroids that share the gas giant’s expansive orbit around the sun. Some of the Trojan asteroids precede Jupiter in its orbit, while others trail it.

Despite their orbits, the Trojans are far from the planet and mostly scattered far from each other. So there’s essentially zero chance of Lucy getting clobbered by one as it swoops past its targets, said Levison of Southwest Research Institute, the mission’s principal scientist.

Lucy will swing past Earth next October and again in 2024 to get enough gravitational oomph to make it all the way out to Jupiter’s orbit. On the way there, the spacecraft will zip past asteroid Donaldjohanson between Mars and Jupiter. The aptly named rock will serve as a 2025 warm-up act for the science instruments.

Drawing power from two huge circular solar wings, Lucy will chase down five asteroids in the leading pack of Trojans in the late 2020s. The spacecraft will then zoom back toward Earth for another gravity assist in 2030. That will send Lucy back out to the trailing Trojan cluster, where it will zip past the final two targets in 2033 for a record-setting eight asteroids visited in a single mission.

It’s a complicated, circuitous path that had NASA’s science mission chief, Thomas Zurbuchen, shaking his head at first. “You’ve got to be kidding. This is possible?” he recalled asking.

Lucy will pass within 600 miles (965 kilometers) of each target; the biggest one is about 70 miles (113 kilometers) across.

“Are there mountains? Valleys? Pits? Mesas? Who knows? I’m sure we’re going to be surprised,” said Johns Hopkins University’s Hal Weaver, who’s in charge of Lucy’s black-and-white camera. “But we can hardly wait to see what … images will reveal about these fossils from the formation of the solar system.”

NASA plans to launch another mission next month to test whether humans might be able to alter an asteroid’s orbit — practice in case Earth ever has a killer rock headed this way.

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The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.

Marcia Dunn, The Associated Press


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Russian actor and director making first movie in space return to Earth after 12-day mission

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A Russian actor and a film director making the first move film in space returned to Earth on Sunday after spending 12 days on the International Space Station (ISS).

The Soyuz MS-18  Space capsule carrying Russian ISS crew member Oleg Novitskiy, Yulia Peresild and Klim Shipenko landed in a remote area outside the western Kazakhstan at 07:35 a.m. (0435 GMT), the Russian space agency Roscosmos said.

The crew had dedocked from the ISS three hours earlier.

Russian State TV footage showed the reentry capsule descending under its parachute above the vast Kazakh steppe, followed by ground personnel assisting the smiling crew as they emerged from the capsule.

However, Peresild, who is best known for her role in the 2015 film “Battle for Sevastopol”, said she had been sorry to leave the ISS.

“I’m in a bit of a sad mood today,” the 37-year-old actor told Russian Channel One after the landing.

“That’s because it had seemed that 12 days was such a long period of time, but when it was all over, I didn’t want to bid farewell,” she said.

Last week 90-year-old U.S. actor William Shatner – Captain James Kirk of “Star Trek” fame – became the oldest person in space aboard a rocketship flown by billionaire Jeff Bezos’s company Blue Origin.

Peresild and Shipenko have been sent to Russian Star City, the home of Russia’s space programme on the outskirts of Moscow for their post-flight recovery which will take about a week, Roscosmos said.

 

(Reporting by Vladimir Soldatkin; Editing by Raissa Kasolowsky)

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