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Part mammal, bird and reptile: Genome mapping reveals how the platypus came to be – CTV News

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EDMONTON —
Ever since Europeans discovered the platypus in the late 1700s, the bizarre, duck-billed, semi-aquatic creature has perplexed researchers.

The creature, with its toothless duck-like bill, webbed feet, ankle spikes full of venom, and glowing fur, stunned researchers with its appearance alone, long before it was discovered that it could both lay eggs and produce milk for its young.

Modern day researchers are still trying to understand how the platypus, largely considered to be the world’s oddest mammal, came to be – until now.

For the first time, researchers at the University of Copenhagen have mapped a complete platypus genome, providing answers to how some of the platypus’ bizarre features emerged.

The platypus belongs to an ancient group of mammals – monotremes – which existed millions of years prior to the emergence of any modern-day mammal.

By comparing the platypus’ genome with that of one of the only other living monotreme species, the short-beaked echidna, researchers can build a better understanding of the genes that led to the creatures’ distinctive traits.

“Indeed, the platypus belongs to the Mammalia class. But genetically, it is a mixture of mammals, birds and reptiles. It has preserved many of its ancestors’ original features — which probably contribute to its success in adapting to the environment they live in,” professor Guojie Zhang, University of Copenhagen researcher, said in a press release.

Monotremes are best known for their unique ability to both lay eggs and nurse their young once they’ve hatched.

Researchers note that one of the platypus’ most unusual characteristics is its ability to feed its hatched young by excreting milk through its sweat.

According to the research, published this week in the journal Nature, during our own evolution, humans lost their vitellogenin genes, which are important for the production of egg yolks. Chickens, for example, have all three of these genes. Instead, we developed casein genes, which are responsible for our ability to produce casein protein, a major component in mammalian milk.

Platypuses still carry one vitellogenin gene, despite having lost the other two roughly 130 million years ago, which allows them to lay eggs. But they also carry the casein genes, allowing the creatures to develop milk that is very similar to cow’s milk.

“It informs us that milk production in all extant mammal species has been developed through the same set of genes derived from a common ancestor which lived more than 170 million years ago, alongside the early dinosaurs in the Jurassic period,” Zhang said.

ONLY ANIMAL WITH 10 SEX CHROMOSOME

The research has also shed light on one of the most perplexing platypus topics – determining the creatures’ sex.

Every other mammal on earth, including humans, have two sex chromosomes. But the platypus has 10, including five Y and five X chromosomes.

Researchers now believe the chromosomes were organized in a ring form, which was later broken away into many small pieces of X and Y chromosomes in ancient monotreme ancestors.

At the same time, the genome mapping reveals that the monotreme sex chromosomes have more in common with chickens than with humans, suggesting an evolutionary link between mammals and birds.

“Decoding the genome for platypus is important for improving our understanding of how other mammals evolved, including us humans,” explained Zhang of the Department of Biology.

“It holds the key as to why we and other eutherian mammals evolved to become animals that give birth to live young instead of egg-laying animals.”​

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Lambton public health warns of COVID-19 vaccine scams – The Beacon Herald

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Public health officials are cautioning residents to be wary of COVID-19 vaccine-related scams circulating throughout the Sarnia area.

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Public health officials are cautioning residents to be wary of COVID-19 vaccine-related scams circulating throughout the Sarnia area.

Lambton public health officials said Friday they’ve heard “several reports” of seniors being contacted since the local online booking system and call centre opened Thursday to residents age 90 and older.

Donna Schmidtmeyer, the health unit’s supervisor of health promotion, said they don’t charge fees to register or to get the vaccine.

“We will not ask you for any financial information whatsoever,” she said in a statement. “And, unless you have called (public health) to pre-register for the vaccine directly or signed up for the pre-registration using our online platform, no one should contact you and ask for any personal information.”

The health unit urged people to check the source of COVID-19 information they’re receiving.

“If you’re unsure or your gut is telling you something is off, it probably is,” the health unit said.

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People are encouraged to call Lambton public health at 519-383-8331 for accurate information.

The warning came amid the province releasing details Friday on the second phase of its vaccine distribution plan. A larger list of Ontarians – people between the ages of 60 and 79 and those with specific health conditions or who can’t work from home – will be included as officials aim to vaccinate nine-million residents between April and July.

More than 4,300 doses of the COVID-19 vaccine have been distributed to Sarnia-area residents – mainly into the arms of seniors and front-line health-care workers and caregivers – as of Wednesday. That figure is expected to climb as fixed-site clinics and mobile teams continue to distribute doses.

The number of COVID-19 cases also climbed Friday, with 122 considered active – nearly double from two days ago – while the overall caseload climbed 24 to 2,187.

A recent spread of the virus at Kettle and Stony Point has contributed to the sudden spike as the community had 26 active cases as of Thursday. Lambton public health’s top medical official said they’re working closely with the First Nation to trace close contacts and to set up a vaccine clinic there.

But a health unit spokesperson said Friday via email the situation is not officially classified as an outbreak. An emergency shelter, the jail, a retirement home and a long-term care facility in Sarnia as well as an unidentified local business and a retirement home in Lambton Shores were all dealing with official outbreaks. The number of cases connected to those facilities has held steady in recent days.

Eight Lambton Kent District and five St. Clair Catholic District school board schools had at least one case linked to them Friday, but they were all still open.

Ontario said Friday it will shift some health units to different colours in its colour-coded restriction system starting next week, but Lambton will stay in red.

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Mars rover travels 6.5 metres in ‘flawless’ first drive – Al Jazeera English

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Perseverance rover can travel 200 metres a day, but scientists need to conduct tests and safety checks before it ventures further.

NASA’s Mars rover Perseverance has taken its first, short drive on the surface of the red planet, two weeks after the robot science lab’s picture-perfect touchdown on the floor of an enormous crater, mission managers said on Friday.

The Perseverance rover first ventured from its landing position Thursday, two weeks after landing on the Red Planet to seek signs of past life.

Taking directions from mission managers at NASA’s Jet Propulsion Laboratory (JPL) near Los Angeles, the rover rolled four metres (13.1 feet) forward, turned about 150 degrees to its left and then drove backwards another 2.5 meters (8.2 feet) for a total of 6.5 metres (21.3 feet) during its half-hour test within Jezero Crater, site of an ancient, long-vanished lake bed and river delta on Mars.

“It went incredibly well,” Anais Zarifian, a JPL mobility test engineer for Perseverance, said during a teleconference briefing with reporters, calling it a “huge milestone” for the mission.

The roundabout, back and forth drive lasted just 33 minutes and went so well that the six-wheeled rover was back on the move Friday.

Perseverance is capable of averaging 200 metres of driving a day.

The surface of Mars directly below NASA’s Mars Perseverance rover is seen using the Rover Down-Look Camera in an image acquired February 22, 2021 [File: NASA/JPL-Caltech/Handout via Reuters]

NASA displayed a photo taken by the rover showing the wheel tread marks left in the reddish, sandy Martian soil after its first drive.

Another vivid image of the surrounding landscape shows a rugged, ruddy terrain littered with large, dark boulders in the foreground and a tall outcropping of rocky, layered deposits in the distance – marking the edge of the river delta.

So far, Perseverance and its hardware, including its main robot arm, appear to be operating flawlessly, according to Robert Hogg, deputy mission manager.

But JPL engineers still have additional equipment checks to run on the rover’s many instruments before they will be ready to send the robot on a more ambitious journey as part of its primary mission to search for traces of fossilised microbial life.

The team has yet to conduct post-landing tests of the rover’s sophisticated system to drill and collect rock samples for return to Earth via future Mars missions.

The deck of NASA’s Perseverance Mars rover, featuring Planetary Instrument for X-ray Lithochemistry, one of the instruments on its stowed arm, is seen in an image taken by the rover’s navigation cameras on Mars February 20, 2021 [File: NASA/JPL-Caltech/Handout via Reuters]

As soon as the system checks on Perseverance are complete, the rover will head for an ancient river delta to collect rocks for return to Earth a decade from now.

Scientists are debating whether to take the smoother route to get to the nearby delta or a possibly tougher way with intriguing remnants from that once-watery time three to four billion years ago.

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NASA's Perseverance rover makes 1st test drive on Mars – CBC.ca

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NASA’s newest Mars rover hit the dusty red road this week, putting 6.5 metres on the odometer in its first test drive.

The Perseverance rover ventured from its landing position Thursday, two weeks after landing on the Red Planet to seek signs of past life.

The roundabout, back-and-forth drive lasted 33 minutes and went so well that more driving was on tap Friday and Saturday for the six-wheeled rover.

“This is really the start of our journey here,” said Rich Rieber, the NASA engineer who plotted the route. “This is going to be like the Odyssey, adventures along the way, hopefully no Cyclops, and I’m sure there will be stories aplenty written about it.”

In its first drive, Perseverance went forward four metres, took a 150-degree left turn, then backed up 2.5 metres. During a news conference Friday, NASA’s Jet Propulsion Laboratory in Pasadena, Calif., shared photos of its tracks over and around small rocks.

“I don’t think I’ve ever been happier to see wheel tracks and I’ve seen a lot of them,” said engineer Anais Zarafian. “This is just a huge milestone for the mission.”

Flight controllers are still checking all of Perseverance’s systems. So far, everything is looking good. The rover’s two-metre robot arm, for instance, flexed its muscles for the first time Tuesday.

Before the car-size rover can head for an ancient river delta to collect rocks for eventual return to Earth, it must drop its so-called protective “belly pan” and release an experimental helicopter named Ingenuity.

As it turns out, Perseverance landed right on the edge of a potential helicopter landing strip — a nice, flat spot, according to Rieber. So the plan is to drive out of this landing strip, ditch the pan, then return for Ingenuity’s highly anticipated test flight. All this should be accomplished by late spring.

WATCH | NASA videos show Perseverance landing on Mars:

NASA’s Mars Perseverance rover safely landed on the surface of the Red Planet last week and, for the first time, the edge-of-your-seat descent was captured in footage from high-definition video cameras, which was released on Monday. The University of Alberta’s Chris Herd walks us through the incredible images. 9:02

Scientists are debating whether to take the smoother route to get to the nearby delta or a possibly tougher way with intriguing remnants from that once-watery time three billion to four billion years ago.

Perseverance — NASA’s biggest and most elaborate rover yet — became the ninth U.S. spacecraft to successfully land on Mars on Feb. 18. China hopes to land its smaller rover — currently orbiting the red planet — in another few months.

NASA scientists, meanwhile, announced Friday that they’ve named Perseverance’s touchdown site in honour of the late science fiction writer Octavia E. Butler, who grew up next door to JPL in Pasadena. She was one of the first Black people to receive mainstream attention for science fiction. Her works included Bloodchild and Other Stories and Parable of the Sower.

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