Science Megathread

[Frodo]

Good thing it's not happening for another 2 billion years:

Looming galactic collision will rip open the black hole at the Milky Way's center

You must be logged in to read this quote.

[Frodo]

Desalinization has its downsides -and it's not just the upfront cost of construction:

UN warns of rising levels of toxic brine as desalination plants meet growing water needs

World's ~16,000 desalination plants discharge 142 million cubic meters of brine daily -- 50 percent more than previously estimated; Enough in a year to cover Florida under a foot (30.5 cm) of brine

[Frodo]

Forest Soil Affected By Fire Or Logging Can Take Almost A Century To Recover

You must be logged in to read this quote.

[Frodo]

For the scientifically minded, were you ever curious to know what exactly caused that huge spike in temperatures ten of millions years ago called the Paleocene-Eocene Thermal Maximum?

Now I think we've found one of the culprits -it was a huge volcanic eruption in Scotland back when it was still as geologically active as East Africa and Indonesia are today:

Skye volcanic eruption 'changed climate'

You must be logged in to read this quote.

And here is a link to the study's summary.

[Frodo]

New Theory: Life on Earth Came From Impact With Another Planet

You must be logged in to read this quote.

[Frodo]

Fossilized Feathers Of Winged Dinosaur Anchiornis Offer Clues To How Birds Evolved To Fly

You must be logged in to read this quote.

And there's an excellent documentary on the Curiosity Channel that helps to illustrate feathered dinosaurs.

[Frodo]

Scientists Create Fabric That Cools When It's Hot And Warms When It's Cold

You must be logged in to read this quote.

[Frodo]

This will make you look at a monument like Stonehenge with a whole different mindset.  Or at least provide context:

Europe’s Megalithic Monuments Originated in France and Spread by Sea Routes, New Study Suggests

You must be logged in to read this quote.

Read more: https://www.smithsonianmag.com/articles/europe-megalithic-monuments-france-sea-routes-mediterranean-180971467/#55m6b20cSZDCjhXk.99

[Frodo]

I am sure some of you have seen the Animal Channel 'mockumentary' from several years ago proposing that there are still remnant populations of Megalodons lurking beneath the ocean depths.  Well, not only are they definitely extinct (thank God), but they became extinct a million years earlier than any of us thought.  And the primary culprit of their demise was the Great White Shark:

Megalodon is definitely extinct—and great white sharks may be to blame
New analysis of the ancient behemoths suggests they disappeared a million years earlier than thought, raising questions about what led to their demise.

Here is a size comparison -basically, Great Whites are about the same size as a juvenile Megalodon:

  

[Frodo]

Thank goodness for GMOs:

How to feed the world by 2050? Recent breakthrough boosts plant growth by 40 percent

[Frodo]

Researchers Succeed In Turning CO2 Back Into Coal

[Frodo]

We may be on the brink of finding a viable alternative to plastic:

Squid Teeth-Inspired Proteins May Provide Eco-Friendly Plastic Alternative

[Frodo]

Imagine the original 'Jurassic Park' with a feathered T-Rex:

A new T. rex exhibit takes a deep dive into the iconic dinosaur

[Frodo]

Apparently the Neanderthal were survived not just by modern humans, but also by their Denisovan cousins:

Denisovans Mated With Modern Humans More Recently Than Previously Thought

[Frodo]

Something to think about before you build your dream home:

Transparent Wood That Can Store And Release Heat Could Be Next Trendy Material In Energy-Efficient Homes

[Frodo]

Fossil Of Ancient Four-Legged Whale Found In Peru

[Frodo]

I'm sure we've all heard by now of the 'hobbits' of Flores Island in the Indonesian archipelago.  They apparently had counterparts on the island of Luzon in the Philippines:

An Ancient Human Species Is Discovered in a Philippine Cave


 

In a cave in the Philippines, scientists have discovered a new branch of the human family tree.

At least 50,000 years ago, an extinct human species lived on what is now the island of Luzon, researchers reported on Wednesday. It’s possible that Homo luzonensis, as they’re calling the species, stood less than three feet tall.

The discovery adds growing complexity to the story of human evolution. It was not a simple march forward, as it once seemed. Instead, our lineage assumed an exuberant burst of strange forms along the way.

[Frodo]

DNA Shows The Denisovans Have At Least 3 Distinct Branches

(...) Findings reveal that interbreeding between modern humans and Denisovans occurred as recently as 15,000 years ago.

However, the researchers also noticed that the genomes of those from Papua New Guinea speak to how complex the Denisovan lineage is. Genetic analyses show that the living Papuans carry genes from two different Denisovan lineages. One has previously been identified in the genes of Papuans and South Asians, while the other has never been identified before.

Even more interestingly, these two Denisovan lineages are genetically different from the Denisovans originally discovered in Siberia.

"What we thought was a single group — Denisovans — was actually three very different groups, with more diversity among them than that seen today in modern humans," Murray Cox, senior author and a population geneticist at the Massey University in New Zealand, tells Live Science.

The newly discovered Denisovan group reportedly split from the other two as far back as 363,000 years ago. It's as genetically different from the original Siberian Denisovans as that group is to the Neanderthals, according to Cox.

[Frodo]

Ice Ages triggered when tropical islands and continents collide

University of California scientists think they know why Earth’s generally warm and balmy climate over the past billion years has occasionally been interrupted by cold snaps that enshroud the poles with ice and occasionally turn the planet into a snowball.

The key trigger, they say, is mountain formation in the tropics as continental land masses collide with volcanic island arcs, such as the Aleutian Islands chain in Alaska.

(...) In a study appearing in this week’s edition of the journal Science, the team concludes that when volcanic arcs collide with continents in the tropics — an inevitable consequence of the planet’s constantly moving tectonic plates — they trigger global cooling, resulting in a glacial climate with extensive ice caps.

Such a collision is going on now as parts of the Indonesian archipelago are pushed upward into mountains on the northern margin of Australia. The result is that there are mountains containing rocks known as ophiolites that have a high capacity to remove carbon from the atmosphere. Over geologic time periods, there is a balancing act between the CO2 emitted from volcanoes and CO2 consumed through chemical reactions with rocks. Rocks with abundant calcium and magnesium, such as ophiolites, are the most efficient at consuming CO2. When these elements are liberated from rocks, they combine with CO2 and make their way to the ocean, where they form limestone, locking CO2 into rock, where it remains for millions of years.

[Frodo]

Now we find Tibetans can trace at least part of their ancestry to the ancient Denisovans -and their shared genes is the reason why they can live full-time at high-altitudes:

First fossil jaw of Denisovans finally puts a face on elusive human relatives

(...) Max Planck paleogeneticists couldn't get DNA from the jaw, but Hublin's graduate student Frido Welker had found in his doctoral work that Neanderthals, modern humans, and Denisovans differ in the amino acid sequence of key proteins. Welker, now a postdoc at the University of Copenhagen, was able to extract collagen, a common structural protein, from a molar of the Xiahe jawbone. He found its amino acid sequence most closely matched that of Denisovans.

Other team members dated a carbonate crust that had formed on the skull by measuring the radioactive decay of uranium in the carbonate. They got a date of 160,000 years ago—a "firm minimum date" for the skull, says geochronologist Rainer Grün of Griffith University in Nathan, Australia, who is not a member of the team.

The date suggests Denisovans would have had tens of thousands of years to adapt to the altitude of Tibet by the time modern humans arrived in the region, some 30,000 to 40,000 years ago. Encounters between modern humans and Denisovans adapted to high altitude could explain how the Tibetans of today came by a Denisovan gene that helps them cope with thin air. "It seems likely that ancestral Tibetans interacted with Denisovans, as they began to move upslope," archaeologist David Madsen of the University of Texas in Austin wrote in an email.

[Frodo]

If you think this is impressive, just wait until the James Webb Space Telescope and Wide Field Infrared Survey Telescope are launched and fully operational:

New Hubble Telescope View of the Evolving Universe

Astronomers have put together the largest and most comprehensive “history book” of galaxies into one single image, using 16 years’ worth of observations from NASA’s Hubble Space Telescope.

The deep-sky mosaic, created from nearly 7,500 individual exposures, provides a wide portrait of the distant universe, containing 265,000 galaxies that stretch back through 13.3 billion years of time to just 500 million years after the big bang. The faintest and farthest galaxies are just one ten-billionth the brightness of what the human eye can see. The universe’s evolutionary history is also chronicled in this one sweeping view. The portrait shows how galaxies change over time, building themselves up to become the giant galaxies seen in the nearby universe.

This ambitious endeavor, called the Hubble Legacy Field, also combines observations taken by several Hubble deep-field surveys, including the eXtreme Deep Field (XDF), the deepest view of the universe. The wavelength range stretches from ultraviolet to near-infrared light, capturing the key features of galaxy assembly over time.

[Frodo]

Iceland turns carbon dioxide to rock for cleaner air

In the heart of Iceland's volcano country, 21st-century alchemists are transforming carbon dioxide into rock for eternity, cleaning the air of harmful emissions that cause global warming.

The technology mimics, in accelerated format, a natural process that can take thousands of years, injecting CO2 into porous basalt rock where it mineralises, capturing it forever.

"With this method we have actually changed the time scale dramatically," says geologist Sandra Osk Snaebjornsdottir.

There's always a 'but':

The main drawback of the method is that it requires large volumes of desalinated water, which, while abundant in Iceland, is rare in many other parts of the planet.

Around 25 tonnes of water are needed for each tonne of carbon dioxide injected.

"That is the Achilles' heel of this method," says Snaebjornsdottir.

"I agree that the process uses a lot of water, but we gain a lot by permanently getting rid of CO2 that otherwise would be floating around the atmosphere," says Aradottir.

Experiments are currently under way to adapt the method to saltwater.

[Frodo]

This takes 'planning ahead' to a whole new level:

Protect solar system from mining 'gold rush', say scientists
Proposal calls for wilderness protection as startup space miners look to the stars

Great swathes of the solar system should be preserved as official “space wilderness” to protect planets, moons and other heavenly bodies from rampant mining and other forms of industrial exploitation, scientists say.

The proposal calls for more than 85% of the solar system to be placed off-limits to human development, leaving little more than an eighth for space firms to mine for precious metals, minerals and other valuable materials.

While the limit would protect pristine worlds from the worst excesses of human activity, its primary goal is to ensure that humanity avoids a catastrophic future in which all of the resources within its reach are permanently used up.

“If we don’t think about this now, we will go ahead as we always have, and in a few hundred years we will face an extreme crisis, much worse than we have on Earth now,” said Martin Elvis, a senior astrophysicist at the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts. “Once you’ve exploited the solar system, there’s nowhere left to go.”

[Frodo]

'Super-Corals' From Hawaii Could Be The Secret To Saving World's Reefs

[Frodo]

First Humans On Mars Will Evolve Into An Entirely New Species Quickly, Says Evolutionary Biologist

(...) While most scientific fields are focused on making the possibility of traveling to and settling on Mars a reality, Scott Solomon, an evolutionary biologist and professor at Rice University, is contemplating about the planet's impact on the human species.

After all, a human colony in Mars would involve humans not only living on the Red Planet, but also reproducing there, Solomon pointed out in a TEDx Talks discussion in 2018. Living in conditions vastly different from Earth is expected to trigger changes in the human babies born there and Solomon has very concrete ideas on what these changes will be.

In an interview with Inverse, Solomon explained that the various evolutionary changes in humans could occur at a much faster rate on Mars than they would on Earth. Within a generation or two, he predicted that human colonizers could already display changes to adapt to the new environment.

"Evolution is faster or slower depending on how much of an advantage there is to having a certain mutation," he explained. "If a mutation pops up for people living on Mars, and it gives them a 50-percent survival advantage, that's a huge advantage, right? And that means that those individuals are going to be passing those genes on at a much higher rate than they otherwise would have."