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Man and dog: Ancient genetics study reveals complex history – FRANCE 24

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Issued on: 29/10/2020 – 19:30Modified: 29/10/2020 – 19:28

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Much of the diversity seen in modern dog populations was already present around the time the last Ice Age had ended 11,000 years ago, a global study of ancient DNA revealed Thursday.

The paper, published in Science, showed how our canine companions spread across the world with their masters, but also found intriguing periods when our shared history was decoupled.

A research team led by the Francis Crick Institute sequenced the genomes of 27 dogs, some of which lived nearly 11,000 years ago, across Europe, the Near East and Siberia.

They found that by this time, well before the domestication of any other animal, there were already at least five different types of dog with distinct genetic ancestries.

Pontus Skoglund of Crick’s Ancient Genomics laboratory, the paper’s senior author, said: “Some of the variation you see between dogs walking down the street today originated in the Ice Age.

“By the end of this period, dogs were already widespread across the northern hemisphere.”

He added this implied that the diversity arose far earlier, “way back in time, during the hunter gatherer Stone Age, the Paleolithic, way before agriculture.”

When and where dogs first diverged from wolves is a contentious matter — analyses of genetic data indicates a window of roughly 25,000-40,000 years ago.

The new paper doesn’t enter this vexed debate but does support the idea that, unlike other animals such as pigs which appear to have been domesticated in multiple locations over time, there is a “single origin” from wolves to dogs.

The scientists found that all dogs probably share a common ancestry “from a single ancient, now-extinct wolf population,” with limited gene flow from wolves since domestication but substantial dog-to-wolf gene flow.

– Convergent evolution –

By extracting and analyzing ancient DNA from skeletal material, the researchers were able to see evolutionary changes as they occurred thousands of years ago.

For instance, European dogs around four or five thousand years ago were highly diverse and appeared to originate from highly distinct populations from Near Eastern and Siberian dogs. But over time, this diversity was lost.

“Although the European dogs we see today come in such an extraordinary array of shapes and forms, genetically they derive from only a very narrow subset of the diversity that used to exist,” said the paper’s lead author Anders Bergstrom.

Evolutionary pathways between our two species have at times followed similar routes.

Humans, for example, have more copies than chimpanzees of a gene that creates a digestive enzyme called salivary amylase, which helps us break down high-starch diets.

Likewise, the paper demonstrated that early dogs carried extra copies of these genes compared to wolves, and this trend only increased over time as their diets adapted to agricultural life.

This builds on previous research that found Arctic sled dogs, like Inuits, have evolved similar metabolic pathways to allow them to process high-fat diets.

There have also been periods when our histories have not run in parallel — for example the loss of diversity that once existed in dogs in early Europe was caused by the spread of single invasive species, an event not mirrored in human migrations.

The field of ancient DNA study has revolutionized the study of our ancestors and researchers are hopeful it can do the same for dogs, our longest animal allies.

“Understanding the history of dogs teaches us not just about their history but also about our own history,” said Bergstrom.

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European Space Agency inks deal to deploy massive space pincers to clean up orbit – ZDNet

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The European Space Agency (ESA) has inked a deal with ClearSpace SA to clean up orbit with craft equipped with pincers designed to grab space junk. 

As space agencies and private companies go beyond research and start exploring the potential of commercial space and tourism, the space ‘junk’ we are accumulating will only grow.

This is a severe issue, considering the smallest satellite or piece of defunct technology zooming around at thousands of meters per second, if it collides with craft or other objects, can cause massive damage that also sends additional debris into space. 

To tackle the problem, the ESA has signed an €86 million contract with startup ClearSpace to fund and launch debris-removal missions. 

Due to launch in 2025, the first active debris removal mission, dubbed ClearSpace-1, will propel a craft into space equipped with pincers able to capture satellites. In this test, the ESA says that ClearSpace craft will “rendezvous, capture and bring down for reentry a Vespa payload adapter.”


ClearSpace

The adapter, a leftover from a 2013 mission, has a mass of 112kg and is roughly the size of a small satellite. 

“Cleaning space is no longer optional,” ClearSpace says in its mission statement. “Removing human-made space debris has become necessary and is our responsibility to ensure that tomorrow’s generations can continue benefiting from space infrastructures and exploration.”

ClearSpace was selected out of 12 candidates in 2019 by the ESA to develop a commercial debris removal solution for space. 

The ESA is only partially funding the mission and the agency intends to raise the rest of the mission cost from commercial investors interested in the technology. 

See also: Intel sends AI to space in launch of a satellite the size of a cereal box

According to the ESA’s latest Space Environment report, there are over 25,000 objects in space — including satellites and various hunks of debris — and rocket bodies, upper stages leftover from launches, and malfunctioning satellites that can’t be deorbited are forms of space junk causing the most concern. 

The majority of objects on the list were launched before 2000 and modern space junk mitigation guidelines were adopted by space agencies. 

In October, IBM revealed a separate project designed to tackle the emerging problem of space junk. A new open source venture between the tech giant and Dr. Moriba Jah at the University of Texas at Austin is focused on predicting where space objects are in orbit, and where they are likely to go. 

By accurately predicting future orbit positions through the creation of machine learning (ML)-based algorithms, this could help companies such as ClearSpace track junk and clean up orbit more effectively. 

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Elon Musk's satellites now streaming to some rural N.B. homes – CBC.ca

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Billionaire Elon Musk’s satellite internet service is now streaming to some homes in New Brunswick.

Starlink has enlisted some households in rural areas of Canada and the northern US to test the service before a full launch, possibly in mid 2021.

Greg Rekounas of the Kingston Peninsula is one of those who signed on to help test the high-speed internet service.

The database administrator, who works from home for an IT company, said he has to be connected at all times.

After barely a week with the new service, he’s bowled over by the difference over his previous DLS link, which sometimes forced him to stop using his camera while participating in work related video-conferencing.

“It changes everything,” said Rekounas. “For me, it was almost to the point where I was considering moving.  And now that thought is out of my head.”

Providing service to people around the world

Musk has been using SpaceX, his rocket company, to blast clusters of 60 low earth orbit satellites into space since May, 2019. The twice-monthly launches have so far planted 955 satellites in low earth orbit, about 550 kilometres above the earth.

The satellites can provide service improvements to people all over the world who are without access to high-speed internet.

A cluster of 60 Starlink satellites is launched from a SpaceX rocket earlier this year. There are 955 units that orbit the earth and 11,000 more are to be launched by 2024. (SpaceX, via Twitter)

Rekounas said it will certainly be welcome in homes in rural parts of New Brunswick.

“They’re able to video conference, they’re able to download, they’re able to stream. They’re able to stay connected almost a hundred per cent of the time,” he said.

Service comes with a price

Upfront costs could be a barrier to some.  Rekounas paid $820 for the required Starlink hardware, a satellite receiving dish, modem, power supply and 100 feet of cable.

The subscription fee is then $130 a month.

The goal is to have 12,000 in orbit by 2024. 

SpaceX did not respond Thursday to a CBC interview request.

Musk is expected to face tough competition from Amazon owner Jeff Bezos, who has his own rocket company, Blue Origin, and is planning an alternate satellite internet service with 3,200 spacecraft in low earth orbit.

Another company, Telesat, which originates in Canada, also has plans to enter the low earth orbit internet market with 298 satellites.

The thousands of new satellites, and others likely to follow, are raising questions about the potential impact on the night skies and on the science of astronomy.

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Thailand: Rare whale skeleton discovered – BBC News

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.css-14iz86j-BoldTextfont-weight:bold;An almost perfectly preserved whale skeleton thought to be between 3,000 and 5,000 years old has been discovered in Thailand.

The bones were found in early November some 12km (7.5 miles) off the coast just to the west of Bangkok.

The 12m (39ft) long skeleton is thought to be that of a Bryde’s whale.

Experts hope the find might provide “a window into the past,” especially for research on sea levels and biodiversity.

The partially fossilised bones are “a rare find,” mammal researcher Marcus Chua of the National University of Singapore told the BBC.

“There are few whale subfossils in Asia,” he said, and even fewer ones are “in such good condition”.

Pictures shared by Thailand’s environment minister Varawut Silpa-archa show the bones apparently almost entirely intact.

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Whale skeleton with researchers

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According to the politician, more than 80% of the skeleton has so far been recovered, including vertebrae, ribs, fins and one shoulder blade.

The skeleton’s head alone is estimated to be about 3m in length.

Mr Chua says the discovery will allow researchers to find out more about the particular species in the past, whether there were any differences compared to today’s Bryde’s whales.

The skeleton will also provide information about the “paleobiological and geological conditions at that time, including sea level estimation, types of sediments, and the contemporary biological communities at that time”.

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“So this find provides a window into the past once the skeleton has been dated,” Mr Chua says.

The bones are yet to be carbon-dated to determine their exact age, with the results expected in December.

Whale skeleton

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The gulf of Thailand has an interesting history in the last 10,000 years, the biologist points out, with sea levels possibly up to 4m higher than today and active tectonic activity.

The skeleton was found off the current coastline in Samut Sakhon.

Bryde’s whales, which live worldwide in warm temperate and tropical waters, are still found in the waters around Thailand today.

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