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Previously Unknown Mass Extinction Occurred 30 Million Years Ago in Africa and Arabia – Sci-News.com

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Nearly 63% of Afro-Arabian mammalian species went extinct approximately 30 million years ago (Oligocene epoch), after Earth’s climate shifted from swampy to icy.

A Pleistocene landscape. Image credit: Roman Uchytel, via the Netherlands Institute of Ecology.

In a new study, University of Salford’s Dr. Dorien de Vries and colleagues looked at fossils of five mammal groups: (i) a group of extinct carnivores called hyaenodonts; two rodent groups: (ii) the anomalures (scaly-tail squirrels) and (iii) the hystricognaths (a group that includes porcupines and naked mole rats); and two primate groups: (iv) the strepsirrhines (lemurs and lorises) and (v) the anthropoids (apes and monkeys).

By gathering data on hundreds of fossils from multiple sites in Africa, they were able to build evolutionary trees for these groups, pinpointing when new lineages branched out and time-stamping each species’ first and last known appearances.

Their results show that all five mammal groups suffered huge losses around the Eocene-Oligocene boundary.

“It was a real reset button. After a few million years, these groups start popping up again in the fossil record, but with a new look,” Dr. de Vries said.

“The fossil species that re-appear later in the Oligocene, after the big extinction event, are not the same as those that were found before.”

“It’s very clear that there was a huge extinction event, and then a recovery period,” said Dr. Steven Heritage, a researcher at Stony Brook University and the Duke Lemur Center Museum of Natural History.

The evidence is in the teeth of these animals. Molar teeth can tell a lot about what a mammal eats, which in turns tells a lot about their environment.

The rodents and primates that reappeared after a few million years had different teeth. These were new species, who ate different things, and had different habitats.

“We see a huge loss in tooth diversity, and then a recovery period with new dental shapes and new adaptations,” Dr. de Vries said.

“Extinction is interesting in that way. It kills things, but it also opens up new ecological opportunities for the lineages that survive into this new world,” said Dr. Matt Borths, curator of the Duke Lemur Center Museum of Natural History.

This decline in diversity followed by a recovery confirms that the Eocene-Oligocene boundary acted as an evolutionary bottleneck: most lineages went extinct, but a few survived.

Over the next several millions of years, these surviving lines diversified.

“In our anthropoid ancestors, diversity bottoms out to almost nothing around 30 million years ago, leaving them with a single tooth type,” said Professor Erik Seiffert, a researcher in the Keck School of Medicine at the University of Southern California, the Duke Lemur Center Museum of Natural History, and the Department of Mammalogy at the Natural History Museum of Los Angeles County.

“That ancestral tooth shape determined what was possible in terms of later dietary diversification.”

“There’s an interesting story about the role of that bottleneck in our own early evolutionary history.”

“We came pretty close to never existing, if our monkey-like ancestors had gone extinct 30 million years ago. Luckily they didn’t.”

The study was published in the journal Communications Biology.

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D. de Vries et al. 2021. Widespread loss of mammalian lineage and dietary diversity in the early Oligocene of Afro-Arabia. Commun Biol 4, 1172; doi: 10.1038/s42003-021-02707-9

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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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Health Canada recalls BC cannabis product due to powdery mildew contamination – Aldergrove Star – Aldergrove Star

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Health Canada and Joint Venture Craft Cannabis have issued a recall notice on a B.C.-based cannabis product due to contamination from powdery mildew.

The recall affects a batch of Bud Coast–Saltspring OG Shark dried cannabis in 3.5 gram units distributed by the B.C. Liquor Distribution Branch. According to Health Canada’s recall notice, 1,071 units were sold between Sept. 22 and Oct. 7

“The affected product may contain powdery mildew. In certain individuals, exposure may result in allergic symptoms such as sneezing, coughing, wheezing, runny nose or nasal congestion, and watery or itchy eyes,” the notice reads.

Anyone who may have purchased the contaminated cannabis should stop using the product immediately and return the product to the retailer where they purchased it.

Exposure to mouldy cannabis products can cause temporary adverse health consequences, but neither Health Canada nor Joint Venture have received any adverse reaction reports about the recalled cannabis.


@SchislerCole
cole.schisler@bpdigital.ca

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NASA launches first space probe to study Jupiter's Trojan asteroids – Ottawa Citizen

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NASA is poised to send Lucy, its first spacecraft to study Jupiter’s Trojan asteroids, to glean new insights into the solar system’s formation 4.5 billion years ago, says the space agency

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NASA launched a first-of-its kind mission on Saturday to study Jupiter’s Trojan asteroids, two large clusters of space rocks that scientists believe are remnants of primordial material that formed the solar system’s outer planets.

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The space probe, dubbed Lucy and packed inside a special cargo capsule, lifted off on schedule from Cape Canaveral Air Force Station in Florida at 5:34 a.m. EDT (0934 GMT), NASA said. It was carried aloft by an Atlas V rocket from United Launch Alliance (UAL), a joint venture of Boeing Co and Lockheed Martin Corp.

Lucy’s mission is a 12-year expedition to study a record number of asteroids. It will be the first to explore the Trojans, thousands of rocky objects orbiting the sun in two swarms – one ahead of the path of giant gas planet Jupiter and one behind it.

The largest known Trojan asteroids, named for the warriors of Greek mythology, are believed to measure as much as 225 kilometers (140 miles) in diameter.

A United Launch Alliance Atlas V rocket with the Lucy spacecraft launches, in this 2 minute and 30 second exposure, from Space Launch Complex 41, on Oct. 16, 2021.
A United Launch Alliance Atlas V rocket with the Lucy spacecraft launches, in this 2 minute and 30 second exposure, from Space Launch Complex 41, on Oct. 16, 2021. Photo by Bill INGALLS / NASA / AFP /Getty

Scientists hope Lucy’s close-up fly-by of seven Trojans will yield new clues to how the solar system’s planets came to be formed some 4.5 billion years ago and what shaped their present configuration.

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Believed to be rich in carbon compounds, the asteroids may even provide new insights into the origin of organic materials and life on Earth, NASA said.

Lucy is named after an ancient fossil that provided insights into the evolution of human species.
Lucy is named after an ancient fossil that provided insights into the evolution of human species. Photo by Bill INGALLS / NASA / AFP /Getty

“The Trojan asteroids are leftovers from the early days of our solar system, effectively the fossils of planet formation,” principal mission investigator Harold Levison of the Southwest Research Institute in Boulder, Colorado, was quoted by NASA as saying.

No other single science mission has been designed to visit as many different objects independently orbiting the sun in the history of space exploration, NASA said.

NASA launched Lucy on a 12-year mission to explore Jupiter’s Trojan asteroids for the first time, gathering new insights into the solar system’s formation.
NASA launched Lucy on a 12-year mission to explore Jupiter’s Trojan asteroids for the first time, gathering new insights into the solar system’s formation. Photo by BILL INGALLS/NASA/AFP /Getty

As well as the Trojans, Lucy will do a fly-by of an asteroid in the solar system’s main asteroid belt, called DonaldJohanson in honor of the lead discoverer of the fossilized human ancestor known as Lucy, from which the NASA mission takes its name. The Lucy fossil, unearthed in Ethiopia in 1974, was in turn named for the Beatles hit “Lucy in the Sky with Diamonds.”

Lucy the asteroid probe will make spaceflight history in another way. Following a route that circles back to Earth three times for gravitational assists, it will be the first spacecraft ever to return to Earth’s vicinity from the outer solar system, according to NASA.

The probe will use rocket thrusters to maneuver in space and two rounded solar arrays, each the width of a school bus, to recharge batteries that will power the instruments contained in the much smaller central body of the spacecraft.

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