Category Archives: Evolution

Its impossible to say how the coronavirus will continue to evolve. Those changes, after all, are a result of random mutations.

But there are some fundamental principles that explain why the virus has morphed as it has, principles that could guide our understanding of its ongoing evolution and what that means for our future with the pathogen.

The great fear is that nature could spit out some new variant that completely saps the power of vaccines and upends the progress weve made against the pandemic. But to virologists and immunologists, such a possibility seems very unlikely.

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Thats not to say variants wont impair immune protection. Already, it appears Delta is causing breakthrough infections and symptomatic cases at higher rates than other variants. But vaccines have shown they dont lose much oomph at protecting people from hospitalization and death, no matter the variant theyre up against. The way the vaccines work leaves experts optimistic that mutations wont suddenly leave everyone vulnerable again.

I dont think that well end up with variants that completely escape antibodies or vaccine-induced immunity, said vaccinologist Florian Krammer of Mount Sinais Icahn School of Medicine. Already, Krammer said, weve seen the immune systems ability to neutralize viral variants drop to the greatest degree with the Beta variant but it still persists. Because of that, vaccines havent lost major steps at protecting people from the worst outcomes of Covid-19.

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Something unexpected could happen, scientists caution another twist in a pandemic full of them. Already, theyve had to reassess their thinking about the coronavirus evolution. This family of viruses proofreads itself as it replicates, which means it picks up mutations more slowly than viruses like influenza. For the first several months of the pandemic, the virus didnt seem to be changing in dramatic ways. But now, variants are dominating the conversation.

This virus has been surprising us, said Ramn Lorenzo-Redondo, a molecular virologist at Northwestern Universitys Feinberg School of Medicine.

Below, STAT outlines some of the key questions about the virus evolution and what it means going forward.

Why does the virus keep getting more transmissible?

When the coronavirus started circulating among people in late 2019, it was already quite the spreader. Cases overwhelmed Wuhan and led China to impose what were then jaw-dropping lockdowns.

But to the virus, people were a new host. A change in its RNA genome had enabled it to infect our cells, replicate inside them, and jump to other people, but the pathogen hadnt had much of a chance to figure us out yet. It had a lot of room to get better at using us to proliferate.

That meant there were a lot of low-hanging fruit mutations that the virus could pick up and that would give it a competitive advantage over other iterations of the virus. Its not that the virus was knowingly figuring out which mutations would make it a better spreader. But as the virus made copies of itself, sometimes it made errors. And by chance, some of those errors gave it a boost over its siblings, helping it outcompete them.

Its happened throughout the pandemic. An early change dubbed D614G led to a strain that was better at spreading than the very first version, enabling that variant to sweep around the world. For a while, that strain was dominant, but then Alpha appeared, and now Delta. Each subsequent iteration was a more effective spreader than the strains before it, so it outran the others. (One note about Alpha: scientists believe it emerged from a person who was immunocompromised and had a rare chronic Covid-19 infection, which allowed the virus to pick up a lot of mutations in a relatively quick period in one host, and then spread from there.)

One way to think about a virus transmissibility is on a curve, one that rises fast and tapers off toward some peak ability. Its going to get better at spreading comparatively quickly, particularly when theres been uncontrolled transmission for a year and a half. Over time, it could evolve more slowly, with fewer new combinations of mutations that might increase its transmissibility. Some scientists have questioned whether Delta is so transmissible that the virus might be nearing the flatter part of the curve. But to virologist Adam Lauring of the University of Michigan, We just dont know where we are in terms of that leveling off. Its possible then, that the virus could still stumble upon mutations that help it spread even more efficiently.

The virus could change in other ways too. If theres one silver lining about Delta, its that its so transmissible that its crowded out other variants that are more worrying from an immune perspective, namely Beta, as well as Gamma. But scientists caution that theres no fundamental reason why a variant couldnt emerge that combines Deltas spreading prowess with Betas ability to partially sneak around immune responses.

Such a variant might look different than we would imagine. Sometimes combining mutations that would seem to maximize transmissibility and immune-dodging abilities actually leads to a virus that fizzles out. Variants that can escape the immune response might be inept at hacking into cells to cause infections. But more worrisome variants are possible, and the best way to prevent them, experts say, is cutting transmission.

How will all this change as more people are protected?

Because basically everyone on the planet was susceptible to Covid-19 at first, the fastest-spreading variant has been able to outrun others. But as the environment changes, the pressures that select for certain characteristics do as well. And instead of a sprinter like Delta, a bulldozer could eventually get the advantage.

Take Beta and Gamma. These variants, which respectively appeared in South Africa and Brazil, emerged in areas that had massive first waves. Thats led to one hypothesis that the variants took off because they could circulate better among people who had previous infections. Viruses that didnt have those features couldnt find as many new cells to infect, and fell back.

Scientists cant say for sure thats what happened with Beta and Gamma perhaps they were just more transmissible in other ways. But it still holds that variants that have some ability to get around the immune response will get the upper hand in populations with greater levels of protection. They might not be causing severe disease in people who are protected whether from vaccination or past infection but if they can cause infections in at least some of those people and transmit from there, their prevalence will increase over other variants that have a harder time causing infections in protected people. (This appears to be happening with Delta to an extent, given that its now known that some vaccinated people transmit the variant.)

When populations have high levels of immunity, it favors [variants] that have some sort of escape mutation that doesnt throw a monkey wrench in the transmission side of things, said Michael Worobey, a professor of evolutionary biology at the University of Arizona.

Now, you may be wondering: If thats the case, does that mean a population thats largely vaccinated will actually encourage the virus to evade protection?

Different forces are at play here. But one key factor is that by cutting how much the virus replicates both through preventing infections and by shortening the infections that do occur vaccines limit the likelihood of additional, more dangerous variants. People who are protected against the virus can act as evolutionary dead ends.

The pressure is there, but the opportunity is not, said Jeremy Kamil, a virologist at Louisiana State University Health Shreveport. The virus has to replicate in order to mutate, but each virus doesnt get many lottery tickets in a vaccinated person whos infected.

How will the virus future evolution affect vaccine protection?

The nightmare scenario is the virus changes in ways that completely escape immune response but that preserve its lethality and transmissibility. But many experts say that a sudden appearance of such a strain seems exceedingly unlikely. Variants could dent some of the defenses vaccines give us, but the immune response should still generally be able to protect us against severe disease.

A virus just cant change a couple amino acids and completely evade the totality of the immune response, said virologist Angela Rasmussen of the University of Saskatchewans Vaccine and Infectious Disease Organization, referring to the building blocks that make up the virus.

Our first line of defenders is antibodies, some of which are trained to recognize specific pieces of the virus and prevent it from infecting cells. If mutations change those components akin to putting on a fake mustache and sunglasses then perhaps the antibodies geared to identify the virus upper lip or eyes might be fooled. The virus could gain a toehold and start an infection. But the vaccines have primed our bodies to recognize other parts of the virus, and to have waves of responders. Antibodies that latch on to other parts of the virus could kick in, and immune cells that help clear out infections before they cause much damage could arrive as reinforcements.

No vaccine is perfect. A small number of people get hospitalized with Covid-19 or even die after being vaccinated, often those with other health conditions. And its possible that variants could cause the vaccines to lose some of their effectiveness: perhaps they cause symptomatic disease at higher rates, and even increase the rate of severe disease or death by a hair. Concerns about the immune response waning in general, combined with the partial escape potential of Delta, are driving the debate about boosters, at least for certain groups of people. But overall, the vaccines are so protective that many virologists while cautioning they cant guarantee it dont see some variant arriving that alone upends the power of the shots.

One future for the virus is that it reaches some stability but then continues to change in small ways. People could become susceptible to an infection over time (whether thats every year or after several years isnt known and will likely vary) but will still generally be protected from worse outcomes. And with every exposure to the virus, including exposure-mimicking vaccines, our bodies will get better at warding it off, maybe even without symptoms. In that way, SARS-CoV-2 will eventually become another endemic respiratory virus.

The indications are that immunity is really protective against hospitalization and death, even if were going to be stuck in a groundhog day world where the virus keeps infecting people year after year even after theyve been exposed, Worobey said.

A lab study, published as a preprint this month, found that even if a variant emerged that could escape the immune protection people have a scenario that study author and virologist Paul Bieniasz of Rockefeller University called extremely unlikely to happen suddenly a booster shot could raise antibody levels to the point where people could fend off the evolved virus. Similarly, if the virus continues to evolve and leads to a more gradual erosion of immune protection, an extra jab could handle it, perhaps one thats tweaked to better suit the changes in the virus.

Even if the virus acquires those resistance mutations, its possible to generate an immune response thatll cope with that, Bieniasz said.

Helen Branswell contributed reporting.

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Why the coronavirus changed over time, and what it means going forward - STAT

CHICAGO, Aug. 19, 2021 /PRNewswire/ -- Rush Street Interactive (NYSE: RSI) ("RSI"), a Chicago-based gaming company, has partnered with Evolution (Nasdaq Stockholm: EVO) to be among the first online casino operators in Michigan to debut the global entertainment company's fan favorite Red Tiger game studio on BetRivers.com. The newly launched games include Bounty Raid, 777 Strike and Reel Keeper. These popular games will soon be joined by Red Tiger's Cash Vault, Piggy Riches Megaways and Gonzo's Quest Megaways which are already player favorites on BetRivers.com in Pennsylvania.

"We are excited to partner with Evolution to bring these top quality and much-loved Red Tiger casino games to our players in Michigan," said Richard Schwartz, CEO of RSI, which operates BetRivers.com. "RSI was the first to debut the Red Tiger games in the U.S. where they are already some of the top performing games in Pennsylvania. We are thrilled to now launch Red Tiger in Michigan where we are sure these games will become fan favorites for our loyal players there as well."

Evolution's acquisition of Red Tiger Gaming combined two of the most innovative and respected online gaming companies, so its Commercial Director for North America says partnering with RSI, a market leader in online casino gaming, only made sense for their debut into Michigan.

"We're very proud to be partnering with RSI, a highly acclaimed U.S. operator, to debut our very successful Red Tiger games in Michigan," said Jeff Millar, Commercial Director, North America for Evolution. "This collaboration with RSI will allow us to deliver these popular games to other markets in the U.S. in an accelerated fashion and will help strengthen our position as a top provider in the online casino category."

Forward-Looking StatementsThis press release includes "forward-looking statements" within the meaning of the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995. RSI's actual results may differ from their expectations, estimates and projections and consequently, you should not rely on these forward-looking statements as predictions of future events. Words such as "expect," "estimate," "project," "budget," "forecast," "anticipate," "intend," "plan," "may," "will," "could," "should," "believes," "predicts," "potential," "continue," and similar expressions are intended to identify such forward-looking statements. These forward-looking statements include, without limitation, RSI's expectations about its partnership with Evolution and the anticipated products and services made available in connection with that partnership. These forward-looking statements involve significant risks and uncertainties that could cause the actual results to differ materially from the expected results. Most of these factors are outside RSI's control and are difficult to predict. Factors that may cause such differences include, without limitation, changes in applicable laws or regulations, unanticipated product or service delays, and other risks and uncertainties indicated from time to time in RSI's most recent Annual Report on Form 10-K, including those under "Risk Factors" therein, and in RSI's other filings with the SEC. RSI cautions that the foregoing list of factors is not exclusive. RSI cautions readers not to place undue reliance upon any forward-looking statements, which speak only as of the date made. RSI does not undertake or accept any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements to reflect any change in its expectations or any change in events, conditions or circumstances on which any such statement is based.

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About RSI

RSI is a trusted online gaming and sports entertainment company focused on regulated markets in the United States and Latin America. Through its brands, BetRivers.com and PlaySugarHouse.com, RSI was an early entrant in many regulated jurisdictions and is currently live with real-money mobile, online and/or retail operations in ten U.S. states: Pennsylvania, Illinois, New Jersey, New York, Michigan, Indiana, Virginia, Colorado, Iowa and West Virginia. RSI is also active internationally, offering its online casino and sportsbook in the regulated gaming market of Colombia on RushBet.co. RSI offers, through its proprietary online gaming platform, some of the most popular online casino games and sports betting options in the United States. Founded in 2012 in Chicago by gaming industry veterans, RSI was named the 2020 Global Gaming Awards Digital Operator of the Year and the 2021 EGR North America Awards Casino Operator of the Year, Customer Services Operator of the Year and Social Gaming Operator of the Year. RSI is committed to industry-leading responsible gaming practices and seeks to provide its customers with the resources and services they need to play responsibly. For more information, visit http://www.rushstreetinteractive.com.

About Evolution

Evolution Gaming Group AB (publ) ("Evolution") develops, produces, markets and licenses fully-integrated B2B Live Casino solutions to gaming operators. Since its inception in 2006, Evolution has developed into a leading B2B provider with 500+ operators among its customers. The group currently employs about 10,000+ people in studios across Europe and in North America. The parent company is based in Sweden and listed on Nasdaq Stockholm with the ticker EVO. Visit http://www.evolution.com for more information.

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Rush Street Interactive Partners With Evolution To Debut Its Red Tiger Online Casino Games In Michigan At BetRivers.com - Yahoo Finance

PERTH (miningweekly.com) Gold miner Evolution Mining has reported record statutory net profit for the 2021 financial year ended June, despite a 4% decline in revenues.

Statutory net profits after tax for the full year reached A$345.3-million, up from the A$301.6-million reported in the last financial year, while underlying net profits after tax declined from the A$405.4-million in 2020 to A$354.3-million.

Earnings before interest, taxes, depreciation and amortisation declined from A$1.02-billion to A$914.2-million.

Gold production during the full year also declined from 680 788 oz, down from the 746 463 oz produced in the previous financial year, resulting in revenue declining from A$1.94-billion to A$1.86-million in the same period.

Total gold sold equalled 677 150 oz, which included deliveries into the Australian gold delivery commitments of 100 000 oz at an average price of A$1 829/oz and Canadian hedge book of 40 000 oz at an average price of C$2 272/oz. Evolution noted that the remaining 537 150 oz were sold in the spot market comprising 456 001 oz delivered at an average price of A$2 474/oz and 81 169 oz delivered at an average price of C$2 361/oz.

Copper revenue achieved was a record with a 26% increase from the prior year to A$236.9-million, driven by a 33% increase in copper price of A$11 172/t partially offset by a 5% decrease in production to 21 361 t.

I am proud of Evolutions achievements during 2021 amid the challenging backdrop of the Covid-19 pandemic. Our teams have risen to the challenge to deliver a record net profit and maintain our sector leading margins. The fully franked final dividend of 5c per share is our seventeenth consecutive dividend, with A$943-million in dividends paid to shareholders since our maiden dividend in 2013, said executive chairperson Jake Klein.

We continued to upgrade the quality of the portfolio with our commitment to develop the Cowal underground mine, and district consolidations completed at both Red Lake and Mungari to further enhance those cornerstone operations. Evolution is well placed to deliver an exceptional, high margin growth pipeline.

Evolution recently approved the A$380-million development of the Cowal underground mine, New South Wales, subject to the receipt of final regulatory approval.

During the ramp-up phase, the underground mine would produce between 0.04-millionand1.1-million tonnes of ore between 2022 and 2024, increasing to between 1.6-million and 1.9-million tonnes during its peak operation between 2025 and 2031, winding down to between 0.9-million and 1.25-million tonnes between 2032 and 2038.

The company also approved a clear and defined programme that accelerates the restoration of its Red Lake mine, in Ontario, to a premier Canadian gold mine with the goal of producing 350 000 oz of low-cost gold ayear by 2026.

In May, Evolution completed the acquisition of all of the outstanding shares of Battle North Gold at a price of C$2.65 a common share in cash for a total consideration of about C$343-million.

Battle North Gold's key asset is the Bateman mill which is located 10 km from Evolutions existing Red Lake operations. The additional processing capacity from the new Bateman mill will accelerate the ability to achieve in excess of 350 000 oz/y from Red Lake. In addition, the expansion of Evolution's footprint in the region provides an opportunity to build on itstrack record as a safe and sustainable operator for the long-term benefit of a broad range of stakeholders.

Furthermore, Evolution earlier this week settled the A$400-million acquisition of fellow-listed Northern Stars Kundana assets, which includethe Kundana operations, a 51% interest in the East Kundana joint venture, full interest in certain tenements making up the Carbine project, and a 75% interest in the West Kundana joint venture.

These operations are some 8 km from Evolutions Mungari operations, and representa strategic opportunity to consolidate the region, optimise existing infrastructure, and capture significant operational synergies.

Looking ahead at 2022, Evolution has set a group gold production target of between 700 000 oz and 760 000 oz, at an all-in sustaining cost of between A$1 220/oz and A$1 280/oz.

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Evolution reports record net profits - Creamer Media's Mining Weekly

New evidence reveals that Arabia was not a mere stopover for ancestral humans leaving Africa, but a lush homeland where they flourished and evolved

By Michael Marshall

Andrea Ucini

THE Rub al-Khali is both desert and deserted a landscape of reddish sand dunes that stretches as far as the eye can see. This hyper-arid region in the south-east of the Arabian peninsula is approximately the size of France. Parts of it often go an entire year without rain. Almost nobody lives there; its name means empty quarter.

The rest of Arabia is less environmentally extreme, but still a very tough place to live without air conditioning and other recent technologies. However, the peninsula wasnt always so parched. A mere 8000 years ago, it was wet enough for there to have been many lakes. The same was true at intervals throughout the past million years, when rivers criss-crossed Arabia, forming green corridors where lush vegetation and wildlife flourished amid the sand dunes. For much of recent geological time, the peninsula was at least partly green.

Arabias verdant past is no mere factoid: it suggests that the region was habitable at times in the distant past. That realisation has prompted archaeologists to start looking for evidence of occupation by humans, their ancestors and their extinct relatives. In just a decade, they have found countless sites where these hominins lived, stretching hundreds of thousands of years into the past. Arabia, it seems, wasnt a mere stopover for hominins as they moved out of Africa into the wider world. It was somewhere they settled for long stretches of time. Indeed, many researchers now think Arabia should be thought of as part of a greater Africa, and that the peninsula played an important role in human evolution and expansion across the world.

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The other cradle of humanity: How Arabia shaped human evolution - New Scientist

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Histology and CT reveal the unique evolution and development of multiple tooth rows in the synapsid Endothiodon | Scientific Reports - Nature.com

No matter how you feel about the sequels, reboots and spin-offs, theres no denying that the first Ghostbusters captured lightning in a bottle in a way that not even the original team could replicate. Sometimes, the right people pop up at the right place and the right time, and the universe gifts us with an unforgettable classic. Of course, this hasnt stopped studios from trying to rekindle that magic with similar projects, and while were all hyped for Jason Reitmans upcoming Ghostbusters: Afterlife, this year marks the 20th anniversary of Ivan Reitmans other attempt at a spiritual successor to his most iconic franchise. Naturally, Im talking about the underrated 2001 monster movie, Evolution.

Originally envisioned by screenwriter Don Jakoby as a hyper-serious horror/sci-fi thriller, Evolution gradually shifted into a completely different direction once Reitman came onboard the project. Inspired by the premise of a group of friends banding together to face an otherworldly threat, the director saw the film as a potential Ghostbusters for the new millennium, with an updated cast of charming oddballs fighting extraterrestrial mutations instead of supernatural entities.

After a series of comedic rewrites, the studio began searching for an ensemble cast with franchise potential. Hot off the heels of The X-Files, David Duchovny was chosen as the sardonic lead that would keep the group together, with Orlando Jones becoming his best friend and partner in crime. The ever-lovable Sean William Scott was also cast as the humorous everyman of the team, with Julianne Moore rounding things out as a clumsy scientist with a heart of gold.

The finished film follows college professors Ira Kane (Duchovny) and Harry Block (Jones) as they investigate a mysterious meteorite that crashes in the Arizona desert. Unfortunately for us humans, the meteorite contains microscopic life-forms that rapidly adapt to their new environment, going through millions of years of evolution in just a few hours as they mutate into monstrous creatures hell-bent on taking over the planet. Knowing that an extinction-level event is at hand, Ira and Harry team up with the CDCs Dr. Allison Reed (Moore) and the aspiring firefighter Wayne Grey (Scott) in order to study the alien menace and devise a plan to save the world, all while butting heads with an inept military response.

Im still mad that we didnt get more of this!

The alien invasion setup may sound familiar, but the formula is solid enough for Evolution to work as a light-hearted sci-fi romp with plenty of impressive monster designs and memorable character moments. Despite wearing its intentions on its sleeve as it attempts to become the next Ghostbusters, the movie actually manages to stand on its own as a retro-styled comedy with an early-2000s twist, and I think its a shame that no one really one talks about it anymore.

From silly moments like watching the aliens reach a primate-like level of intelligence to fun set-pieces like when the crew attempts to bring down a mutated dragon in the middle of a crowded shopping mall, Id argue that the movie is at its best when reveling in its own absurdity. Hell, I know Ill never forget that bizarre finale where dandruff shampoo miraculously saves the day in what can only be described as a cellular enema.

Evolution admittedly stumbles during its transparent attempts at recreating Ghostbusters success (even Dan Aykroyd makes an appearance and the posters three-eyed smiley face is obviously meant to emulate that films highly marketable anti-ghost logo), but the insanely charming cast helps to smooth out most of the rough edges. The dated jokes and familiar tropes are no match for Jones and Duchovnys bromance, and even Sean William Scott gets the chance to shine with ridiculous amounts of dudebro energy. Dr. Reed is the only character that really suffers from the unpolished script, with Moore being relegated to lazy gags despite her legendary acting chops.

Unfortunately, theres also the matter of the films heavy use of early-2000s CGI during its action sequences. While there are a handful of practical puppets on display here, and the designs are all pretty clever, the majority of the monsters are brought to life via wonky computer graphics that havent aged all that well. Thankfully, the movies playful tone keeps the effects from detracting from the experience, though I wish they had gone with the original plan of having the aliens final form be a fleshy humanoid kaiju instead of a gigantic cell.

Where Product Placement and Deus Ex Machinas meet!

Personally, I think Evolution was a single draft (and maybe a Ray Parker Jr. song) away from being a classic, but I still appreciate how it lovingly emulates classic monster movies for a new crowd. From setting the story in the Arizona desert to having a bumbling military force be saved by outcast scientists, the film really nails the 50s sci-fi tropes without feeling like a parody. Hell, even the real science on display here is about as accurate as it was in those movies, and I wouldnt be surprised if a possible sequel involved radiation turning lizards and insects into giant monsters.

Despite spawning a short-lived animated series, its a real shame that Evolution never took off as a franchise. This could have been one of those rare cases where a sequel with already-established characters could have surpassed the original, introducing even wackier monster-movie hijinks with each new installment. They may not be everyones favorite team of paranormal exterminators, but I could have watched hours of Jones and Duchovny bickering about space creatures and the periodic table, and I have a sneaking suspicion that Im not the only one.

As it stands, Evolution doesnt quite live up to its aspirations as a proper successor to the original Ghostbusters, but it definitely stands on its own as a highly entertaining throwback created by a team that clearly cared about the project. It may not have aged as gracefully as its inspirations, but Id recommend this one to any fan of the light-hearted monster flicks of yesteryear. At the very least, youll learn that Head & Shoulders can be useful during an alien invasion, and with the way things are right now, its always good to be prepared.

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The Other Ghostbusters - Celebrating 20 Years of 'Evolution' - Bloody Disgusting

Dec. 2019Mar. 2020Jun. 2020Sep. 2020Dec. 2020Mar. 2021Jun. 2021IotaEpsilonEtaKappaThetaLambdaAlphaDeltaGammaBeta

(Graphic) N. Desai/Science; (Data) NextStrain; GISAID

By Kai KupferschmidtAug. 19, 2021 , 2:05 PM

Each dot above represents a virus isolated from a COVID-19 patient in this family tree of SARS-CoV-2, which shows a tiny subset of the more than 2 million viruses sequenced so far. The World Health Organization currently recognizes four variants of concern and four variants of interest.

Wuhan, China, 26 December 2019OtherVariants of concernKappaEtaIotaLambdaVariants of interestEpsilonFormer variants of interestThetaGamma was first detected in Brazil and spread widely in South America.First spotted in India, Delta is rapidly replacing other variants around the globe.Beta, first seen in South Africa, has shown the strongest evidence of immune escape.First detected in the United Kingdom, Alpha became the first variant to spread widely.

Edward Holmes does not like making predictions, but last year he hazarded a few. Again and again, people had asked Holmes, an expert on viral evolution at the University of Sydney, how he expected SARS-CoV-2 to change. In May 2020, 5 months into the pandemic, he started to include a slide with his best guesses in his talks. The virus would probably evolve to avoid at least some human immunity, he suggested. But it would likely make people less sick over time, he said, and there would be little change in its infectivity. In short, it sounded like evolution would not play a major role in the pandemics near future.

A year on Ive been proven pretty much wrong on all of it, Holmes says.

Well, not all: SARS-CoV-2 did evolve to better avoid human antibodies. But it has also become a bit more virulent and a lot more infectious, causing more people to fall ill. That has had an enormous influence on the course of the pandemic.

The Delta strain circulating nowone of four variants of concern identified by the World Health Organization, along with four variants of interestis so radically different from the virus that appeared in Wuhan, China, in late 2019 that many countries have been forced to change their pandemic planning. Governments are scrambling to accelerate vaccination programs while prolonging or even reintroducing mask wearing and other public health measures. As to the goal of reaching herd immunityvaccinating so many people that the virus simply has nowhere to goWith the emergence of Delta, I realized that its just impossible to reach that, says Mge evik, an infectious disease specialist at the University of St. Andrews.

Yet the most tumultuous period in SARS-CoV-2s evolution may still be ahead of us, says Aris Katzourakis, an evolutionary biologist at the University of Oxford. Theres now enough immunity in the human population to ratchet up an evolutionary competition, pressuring the virus to adapt further. At the same time, much of the world is still overwhelmed with infections, giving the virus plenty of chances to replicate and throw up new mutations.

Predicting where those worrisome factors will lead is just as tricky as it was a year and a half ago, however. Were much better at explaining the past than predicting the future, says Andrew Read, an evolutionary biologist at Pennsylvania State University, University Park. Evolution, after all, is driven by random mutations, which are impossible to predict. Its very, very tricky to know whats possible, until it happens, Read says. Its not physics. It doesnt happen on a billiard table.

Still, experience with other viruses gives evolutionary biologists some clues about where SARS-CoV-2 may be headed. The courses of past outbreaks show the coronavirus could well become even more infectious than Delta is now, Read says: I think theres every expectation that this virus will continue to adapt to humans and will get better and better at us. Far from making people less sick, it could also evolve to become even deadlier, as some previous viruses including the 1918 flu have. And although COVID-19 vaccines have held up well so far, history shows the virus could evolve further to elude their protective effectalthough a recent study in another coronavirus suggests that could take many years, which would leave more time to adapt vaccines to the changing threat.

Holmes himself uploaded one of the first SARS-CoV-2 genomes to the internet on 10 January 2020. Since then, more than 2 million genomes have been sequenced and published, painting an exquisitely detailed picture of a changing virus. I dont think weve ever seen that level of precision in watching an evolutionary process, Holmes says.

Making sense of the endless stream of mutations is complicated. Each is just a tiny tweak in the instructions for how to make proteins. Which mutations end up spreading depends on how the viruses carrying those tweaked proteins fare in the real world.

The vast majority of mutations give the virus no advantage at all, and identifying the ones that do is difficult. There are obvious candidates, such as mutations that change the part of the spike proteinwhich sits on the surface of the virusthat binds to human cells. But changes elsewhere in the genome may be just as crucialyet are harder to interpret. Some genes functions arent even clear, let alone what a change in their sequence could mean. The impact of any one change on the virus fitness also depends on other changes it has already accumulated. That means scientists need real-world data to see which variants appear to be taking off. Only then can they investigate, in cell cultures and animal experiments, what might explain that viral success.

The most eye-popping change in SARS-CoV-2 so far has been its improved ability to spread between humans. At some point early in the pandemic, SARS-CoV-2 acquired a mutation called D614G that made it a bit more infectious. That version spread around the world; almost all current viruses are descended from it. Then in late 2020, scientists identified a new variant, now called Alpha, in patients in Kent, U.K., that was about 50% more transmissible. Delta, first seen in India and now conquering the world, is another 40% to 60% more transmissible than Alpha.

SARS-CoV-2 variants began to emerge in 2020. Alpha surged in many countries in early 2021, then was largely replaced by Delta. Two other variants of concern, Beta and Gamma, account for a smaller number of cases.

(Graphic) N. Desai/Science; (Data) NextStrain; GISAID

Read says the pattern is no surprise. The only way you could not get infectiousness rising would be if the virus popped into humans as perfect at infecting humans as it could be, and the chance of that happening is incredibly small, he says. But Holmes was startled. This virus has gone up three notches in effectively a year and that, I think, was the biggest surprise to me, Holmes says. I didnt quite appreciate how much further the virus could get.

Bette Korber at Los Alamos National Laboratory and her colleagues first suggested that D614G, the early mutation, was taking over because it made the virus better at spreading. She says skepticism about the virus ability to evolve was common in the early days of the pandemic, with some researchers saying D614Gs apparent advantage might be sheer luck. There was extraordinary resistance in the scientific community to the idea this virus could evolve as the pandemic grew in seriousness in spring of 2020, Korber says.

Researchers had never watched a completely novel virus spread so widely and evolve in humans, after all. Were used to dealing with pathogens that have been in humanity for centuries, and their evolutionary course is set in the context of having been a human pathogen for many, many years, says Jeremy Farrar, head of the Wellcome Trust. Katzourakis agrees. This may have affected our priors and conditioned many to think in a particular way, he says.

Another, more practical problem is that real-world advantages for the virus dont always show up in cell culture or animal models. There is no way anyone would have noticed anything special about Alpha from laboratory data alone, says Christian Drosten, a virologist at the Charit University Hospital in Berlin. He and others are still figuring out what, at the molecular level, gives Alpha and Delta an edge.

Alpha seems to bind more strongly to the human ACE2 receptor, the virus target on the cell surface, partly because of a mutation in the spike protein called N501Y. It may also be better at countering interferons, molecules that are part of the bodys viral immune defenses. Together those changes may lower the amount of virus needed to infect someonethe infectious dose. In Delta, one of the most important changes may be near the furin cleavage site on spike, where a human enzyme cuts the protein, a key step enabling the virus to invade human cells. A mutation called P681R in that region makes cleavage more efficient, which may allow the virus to enter more cells faster and lead to greater numbers of virus particles in an infected person. In July, Chinese researchers posted a preprint showing Delta could lead to virus levels in patient samples 1000 times higher than for previous variants. Evidence is accumulating that infected people not only spread the virus more efficiently, but also faster, allowing the variant to spread even more rapidly.

The new variants of SARS-CoV-2 may also cause more severe disease. For example, a study in Scotland found that an infection with Delta was about twice as likely to lead to hospital admission than with Alpha.

It wouldnt be the first time a newly emerging disease quickly became more serious. The 191819 influenza pandemic also appears to have caused more serious illness as time went on, says Lone Simonsen, an epidemiologist at Roskilde University who studies past pandemics. Our data from Denmark suggests it was six times deadlier in the second wave.

A popular notion holds that viruses tend to evolve over time to become less dangerous, allowing the host to live longer and spread the virus more widely. But that idea is too simplistic, Holmes says. The evolution of virulence has proven to be quicksand for evolutionary biologists, he says. Its not a simple thing.

Two of the best studied examples of viral evolution are myxoma virus and rabbit hemorrhagic disease virus, which were released in Australia in 1960 and 1996, respectively, to decimate populations of European rabbits that were destroying croplands and wreaking ecological havoc. Myxoma virus initially killed more than 99% of infected rabbits, but then less pathogenic strains evolved, likely because the virus was killing many animals before they had a chance to pass it on. (Rabbits also evolved to be less susceptible.) Rabbit hemorrhagic disease virus, by contrast, got more deadly over time, probably because the virus is spread by blow flies feeding on rabbit carcasses, and quicker death accelerated its spread.

The myxoma virus was released in Australia in 1950 to control rabbits after trials at this test site on Wardang Island. It has evolved to become less virulent over time, but not all viruses do.

Other factors loosen the constraints on deadliness. For example, a virus variant that can outgrow other variants within a host can end up dominating even if it makes the host sicker and reduces the likelihood of transmission. And an assumption about human respiratory diseases may not always hold: that a milder virusone that doesnt make you crawl into bed, saymight allow an infected person to spread the virus further. In SARS-CoV-2, most transmission happens early on, when the virus is replicating in the upper airways, whereas serious disease, if it develops, comes later, when the virus infects the lower airways. As a result, a variant that makes the host sicker might spread just as fast as before.

From the start of the pandemic, researchers have worried about a third type of viral change, perhaps the most unsettling of all: that SARS-CoV-2 might evolve to evade immunity triggered by natural infections or vaccines. Already, several variants have emerged sporting changes in the surface of the spike protein that make it less easily recognized by antibodies. But although news of these variants has caused widespread fear, their impact has so far been limited.

On this antigenic map, produced by Derek Smith, David Montefiori, and colleagues, the distance between two variants indicates how well antibodies against one neutralize the other.

(Graphic) N. Desai/Science; (Data) Derek Smith/University of Cambridge; David Montefiori/Duke University

Derek Smith, an evolutionary biologist at the University of Cambridge, has worked for decades on visualizing immune evasion in the influenza virus in so-called antigenic maps. The farther apart two variants are on Smiths maps, the less well antibodies against one virus protect against the other. In a recently published preprint, Smiths group, together with David Montefioris group at Duke University, has applied the approach to mapping the most important variants of SARS-CoV-2 (see graphic, right).

The new maps place the Alpha variant very close to the original Wuhan virus, which means antibodies against one still neutralize the other. The Delta variant, however, has drifted farther away, even though it doesnt completely evade immunity. Its not an immune escape in the way people think of an escape in slightly cartoonish terms, Katzourakis says. But Delta is slightly more likely to infect fully vaccinated people than previous variants. It shows the possible beginning of a trajectory and thats what worries me, Katzourakis says.

Other variants have evolved more antigenic distance from the original virus than Delta. Beta, which first appeared in South Africa, has traveled the farthest on the map, although natural or vaccine-induced immunity still largely protects against it. And Betas attempts to get away may come at a price, as Delta has outstripped it worldwide. Its probably the case that when a virus changes to escape immunity, it loses other aspects of its fitness, Smith says.

The map shows that for now, the virus is not moving in any particular direction. If the original Wuhan virus is like a town on Smiths map, the virus has been taking local trains to explore the surrounding area, but it has not traveled to the next citynot yet.

Although its impossible to predict exactly how infectiousness, virulence, and immune evasion will develop in the coming months, some of the factors that will influence the virus trajectory are clear.

One is the immunity that is now rapidly building in the human population. On one hand, immunity reduces the likelihood of people getting infected, and may hamper viral replication even when they are. That means there will be fewer mutations emerging if we vaccinate more people, evik says. On the other hand, any immune escape variant now has a huge advantage over other variants.

In fact, the world is probably at a tipping point, Holmes says: With more than 2 billion people having received at least one vaccine dose and hundreds of millions more having recovered from COVID-19, variants that evade immunity may now have a bigger leg up than those that are more infectious. Something similar appears to have happened when a new H1N1 influenza strain emerged in 2009 and caused a pandemic, says Katia Klle, an evolutionary biologist at Emory University. A 2015 paper found that changes in the virus in the first 2 years appeared to make the virus more adept at human-to-human transmission, whereas changes after 2011 were mostly to avoid human immunity.

It may already be getting harder for SARS-CoV-2 to make big gains in infectiousness. There are some fundamental limits to exactly how good a virus can get at transmitting and at some point SARS-CoV-2 will hit that plateau, says Jesse Bloom, an evolutionary biologist at the Fred Hutchinson Cancer Research Center. I think its very hard to say if this is already where we are, or is it still going to happen. Evolutionary virologist Kristian Andersen of Scripps Research guesses the virus still has space to evolve greater transmissibility. The known limit in the viral universe is measles, which is about three times more transmissible than what we have now with Delta, he says.

Researchers trying to understand which genetic changes make SARS-CoV-2 variants more successful have focused on the spike protein, which studs the viral surface and binds to human cells. Alpha, Beta, and Delta have mutations in three key areas of the protein that may affect the virus infectiousness and its ability to elude the immune system.

(Graphic) N. Desai/Science; (Data) E. Wall et al., The Lancet, 397:10292, 2331 (2021)

The limits of immune escape are equally uncertain. Smiths antigenic maps show the space the virus has explored so far. But can it go much farther? If the variants on the map are like towns, then where are the countrys natural boundarieswhere does the ocean start? A crucial clue will be where the next few variants appear on the map, Smith says. Beta evolved in one direction away from the original virus and Delta in another. Its too soon to say this now, but we might be heading for a world where there are two serotypes of this virus that would also both have to be considered in any vaccines, Drosten says.

Immune escape is so worrying because it could force humanity to update its vaccines continually, as happens for flu. Yet the vaccines against many other diseasesmeasles, polio, and yellow fever, for examplehave remained effective for decades without updates, even in the rare cases where immune-evading variants appeared. There was big alarm around 2000 that maybe wed need to replace the hepatitis B vaccines, because an escape variant had popped up, Read says. But the variant has not spread around the world: It is able to infect close contacts of an infected person, but then peters out. The virus apparently faces a trade-off between transmissibility and immune escape. Such trade-offs likely exist for SARS-CoV-2 as well.

Residents line up outside a vaccination center in Sydney, where a rapidly growing outbreak of the highly contagious Delta variant of SARS-CoV-2 led officials to order a new lockdown in June.

Some clues about SARS-CoV-2s future path may come from coronaviruses with a much longer history in humans: those that cause common colds. Some are known to reinfect people, but until recently it was unclear whether thats because immunity in recovered people wanes, or because the virus changes its surface to evade immunity. In a study published in April inPLOS Pathogens, Bloom and other researchers compared the ability of human sera taken at different times in the past decades to block virus isolated at the same time or later. They showed that the samples could neutralize strains of a coronavirus named 229E isolated around the same time, but werent always effective against virus from 10 years or more later. The virus had evidently evolved to evade human immunity, but it had taken 10 years or more.

Immune escape conjures this catastrophic failure of immunity when it is really immune erosion, Bloom says. Right now it seems like SARS-CoV-2, at least in terms of antibody escape, is actually behaving a lot like coronavirus 229E.

Others are probing SARS-CoV-2 itself. In a preprint published this month, researchers tinkered with the virus to learn how much it has to change to evade the antibodies generated in vaccine recipients and recovered patients. They found that it took 20 changes to the spike protein to escape current antibody responses almost completely. That means the bar for complete escape is high, says one of the authors, virologist Paul Bieniasz of Rockefeller University. But its very difficult to look into a crystal ball and say whether that is going to be easy for the virus to acquire or not, he says.

It seems plausible that true immune escape is hard, concludes William Hanage of the Harvard T.H. Chan School of Public Health. However, the counterargument is that natural selection is a hell of a problem solver and the virus is only beginning to experience real pressure to evade immunity.

And the virus has tricks up its sleeve. Coronaviruses are good at recombining, for instance, which could allow new variants to emerge suddenly by combining the genomesand the propertiesof two different variants. In pigs, recombination of a coronavirus named porcine epidemic diarrhea virus with attenuated vaccine strains of another coronavirus has led to more virulent variants of PEDV. Given the biology of these viruses, recombination may well factor into the continuing evolution of SARS-CoV-2, Korber says.

Given all that uncertainty, its worrisome that humanity hasnt done a great job of limiting the spread of SARS-CoV-2, says Eugene Koonin, a researcher at the U.S. National Center for Biotechnology Information. Some dangerous variants may only be possible if the virus hits on a very rare, winning combination of mutations, he says. It might have to replicate an astronomical number of times to get there. But with all these millions of infected people, it may very well find that combination.

Indeed, Katzourakis adds, the past 20 months are a warning to never underestimate viral evolution. Many still see Alpha and Delta as being as bad as things are ever going to get, he says. It would be wise to consider them as steps on a possible trajectory that may challenge our public health response further.

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New SARS-CoV-2 variants have changed the pandemic. What will the virus do next? - Science Magazine

Editors Note: This is the first article in a two-part series on airpower and Operation Inherent Resolve. The second article explores lessons learned for great-power competition.

On June 27, U.S. fighter jets struck weapons storage facilities used by Iranian proxy groups Kataib Hizballah and Kataib Sayyid al-Shuhada in retaliation for launching drone attacks on U.S. military facilities in the region. This was the second set of airstrikes ordered by the Biden administration in order to deter Iran and its proxies from attacking U.S. equities in the Middle East.

Just several weeks later, U.S. airpower was used once again, but this time in Afghanistan. Over-the-horizon airstrikes sought to bolster Afghan defenses, blunt the Talibans momentum, protect key urban areas, and stave off the collapse of the Afghan state.

President Joe Bidens decision to use fighter jets to strike Iranian infrastructure in Syria and Iraq, and to defend key Afghan cities, follows a familiar pattern. Since the 1991 Gulf War, U.S. presidents have chosen time and time again to use airpower to protect U.S. interests abroad. Since the six-week air campaign that immobilized and demoralized Saddam Husseins forces defending Kuwait, airpower has become the centerpiece of U.S. military interventions in Bosnia and Herzegovina, Kosovo, Afghanistan, Libya, and, once again, Iraq.

The U.S. airstrikes against Iranian-backed militia groups located along the Iraqi-Syrian border, and the uptick in American air support to Afghan forces, demonstrate how the model of airpower perfected against the Islamic State in Iraq and the Levant (ISIL) in Iraq and Syria has evolved. But the limited strikes on Iranian proxies and Taliban forces stand in stark contrast to the continued strikes on Islamic State leaders and targets in Iraq and Syria also authorized by the Biden administration. Previous military successes are just as likely to distort policymakers thinking as prior failures. The Biden administration should not harbor unrealistic expectations about what airpower can achieve, nor should it succumb to the tempation to employ airpower because it is a low-risk form of taking action.

The Evolving Use of Airpower

The five-year fight against the Islamic State may appear like one of the forever wars the Biden administration seeks to end. Instead, it should be viewed as an evolution in how U.S. leaders have leveraged airpower to achieve military and political goals. Yet, it should also be a cautionary tale regarding the limits of airpower, as operational success has not translated into a strategic victory with enduring gains against a now-resurgent ISIL and the ideology it espouses.

The Obama administration leveraged the speed, agility, and precision of airpower when it intervened in Iraq in 2014 to stop the Islamic States expansion in Iraq and Syria. While the U.S.-led coalition mainly fought from the air, Iraqi state and Syrian non-state forces trained and equipped by the coalition led the fight on the ground.

Technological and tactical innovations since the Gulf War enabled a light American footprint more removed from the ground battle in contrast to the heavy boots-on-the-ground approach associated with the wars in Afghanistan and Iraq. Only 10,000 U.S. troops were engaged in Operation Inherent Resolve not primarily to fight, but to support partner ground forces away from the frontlines. This stands in stark contrast to the large conventional force required to liberate Kuwait in 1991, which consisted of a massive ground attack involving hundreds of thousands of U.S. forces.

Inherent Resolve demonstrated a growing sophistication in using airpower. Even without American troops on the battlefield directing the airstrikes, U.S. aircraft could find, fix, and track ISIL targets, and accurately deliver weapons. This feat was enabled by drones, which filled the skies over Iraq and Syria, piping real-time full-motion video to U.S. command posts directing the airstrikes.

Leveraging exquisite intelligence that detailed ISILs operations and expert planning and execution, U.S. aircraft dropped smart bombs that not only usually hit their intended targets, but also limited civilian casualties and unnecessary damage. One coalition airstrike, for example, blew the roof off a building in Mosul, destroying one floor and incinerating an ISIL cash stash inside, while leaving nearby buildings undamaged.

The capabilities of contemporary U.S. airpower have allowed American leaders to intervene in international conflicts while limiting risk to U.S. ground troops, thereby reducing opposition from those wary of putting U.S. boots on the ground. At times, American leaders have employed airstrikes because they wanted to do something and appear strong during a crisis, whether the attacks succeeded or not. But airpower is not without risks. Even with increased precision, modern technology, and stringent measures, airpower cannot avoid civilian casualties. It also is not a sure means for a swift and decisive victory, as the recent resurgence of ISIL fighters has shown.

The Siren Song of Airpower

There are important differences between full-blown air campaigns and bounded strikes, such as those on Iranian targets in Iraq and Syria or recently against the Taliban, in terms of the theory for how airpower will achieve the desired effect. Moreover, they differ in the longevity and intensity of air operations. In the Gulf War and during Inherent Resolve, U.S. leaders correctly applied airpower to achieve the operational aims of liberating illegally seized territory. In both cases, the United States sought to produce a durable outcome the liberation of Kuwait, and the liberation of Iraqi and Syrian territory from ISIL rule.

In contrast, the goal of the recent strikes in Iraq and Syria is less clear. They were a proportional response to Iranian proxy attacks on U.S. facilities and forces in the Middle East, but the linkages of very discrete attacks on these particular targets to broader outcomes is tenuous. Instead, these strikes appear to be another half-hearted attempt at punitive or coercive diplomacy through airstrikes, which have historically failed to have the intended effect due to the limited nature of the attacks and the unclear links to goals.

Already, the Biden administration may be finding this out the hard way. Despite the strikes being intended as a deterrent measure, they have failed to halt attacks on U.S. equities in the region. The recent airstrikes were promptly met by the very type of drone attacks on a U.S. facility in Baghdad the administration sought to halt.

During the withdrawal of American forces from Afghanistan, the Biden administration employed airstrikes to do something as Taliban forces have captured city after city. Initially, these strikes may have been to encourage the Afghans to fight for themselves as Biden has exhorted. This halfhearted support has failed to turn the tide in Afghanistan. Although a much more aggressive air campaign launched earlier could have blunted the Talibans offensive, alone it would not have defeated the Taliban. As the war against ISIL demonstrated, American airpower can halt an offensive, but it alone cannot liberate captured territory. A capable ground force is also needed. Yet, after 20 years of trying and billions of dollars invested, the Afghan military did not emerge as this partner and airpower alone will not liberate Afghanistan from the Taliban.

Airpower is an unusually seductive form of military power because of its immediate effects, distance from the battlefield, and relatively low-risk application. But there are right and wrong ways to apply airpower. Using advanced airpower capabilities in an operation with clear tactical goals as evidenced by the Gulf War and Inherent Resolve may achieve battlefield victories and support foreign policy aims with limited risk to U.S. forces. Employing airpower as a form of coercion in one-off strikes without a precise operational objective, or merely as a way of demonstrating action, is less impressive.

Presidents and their advisers should be mindful that, although innovations in warfighting may achieve tactical and operational aims, they do not guarantee strategic success. Today, although the Islamic States so-called caliphate has been destroyed, groups of well-financed fighters remain active, and the airstrikes against these targets continue. The combined effects of air and landpower can curb threats to regional stability, but they cannot defeat ideology.

At present, it appears as though the Biden administration has seized on airpower as the preferred tool to do something even if it fails to achieve its purported goal as opposed to doing nothing. But this approach has failed to deter further Iranian proxy attacks on U.S. forces in Iraq or to keep the Taliban from taking Kabul. Such actions appear mainly intended to appease domestic critics who accuse Biden of being weak on Iran or abandoning Afghanistan. Moreover, airpower not tied to broader objectives that align with national interests risks unintended consequences, which may undermine the administrations longstanding plans to reduce the U.S. military presence in the Middle East and Afghanistan, and distract from the Pentagons efforts to focus on China.

The Biden administration should be careful to not fall under the siren song of airpower as its preferred method of response. There are times in which military power is the best tool as was the case of Inherent Resolve, where only the combination of ground and airpower could roll back ISILs territorial advance. But there are times in which other instruments of power, particularly diplomacy, may do a better job of protecting U.S. interests, or it is simply best to do nothing. As such, the Biden administration should think twice before calling for airstrikes and should preserve military power for when it is truly needed.

Becca Wasser is a fellow in the defense program at the Center for a New American Security. Stacie L. Pettyjohn is a senior fellow and director of the defense program at the Center for a New American Security. Together, they are the co-authors ofThe Air War Against the Islamic State.

Image: U.S. Air Force (Photo by Senior Airman Duncan C. Bevan)

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From Desert Storm to Inherent Resolve: The Evolution of Airpower - War on the Rocks

Jack Wallen harkens back to the early days of the Linux desktop and how it has changed over the years, bringing the cool he so longed for.

It's been 30 years since Linus Torvalds created Linux. It's been almost 25 years since I first experienced Linux on the desktop.

I remember like it was yesterday. The very first time I booted into the Linux desktop. The distribution in question was Caldera Open Linux 1.0, which installed with kernel 2.0 and the desktop was Fvwm95. I cannot confirm what I had assumed the desktop would have looked like, but I can assure you I had no idea it would have taken on a rather Windows 95 clone-ish look about it.

SEE:5 Linux server distributions you should be using(TechRepublic Premium)

It was ugly. Quite ugly. And not in a retro-kitsch way to make it look ironically or whimsically cool. It was just unsightly. The colors were decidedly too Microsoftian, and it was all so ... clinical.

Fortunately, that desktop didn't last very long with me. Nor did Caldera Open Linux last for more than a week on my desktop. Instead of sticking with that particular distribution (before I even knew what a distribution was), I jumped ship for Red Hat 4.2 (prior to Red Hat becoming RHEL). Once again, I found myself with a desktop that looked more at home in a university research lab than my PC.

Something had to give.

I cannot be sure why, at such an early stage in my Linux career, aesthetics was so important to me, but I know I'd read so much about how flexible and cool Linux was. But where was the cool? Certainly not in Fvwm95, CDE or most of the default desktops of the time.

Or so I thought.

Eventually, I connected with a Linux guru who taught me a great deal about Linux in a very short period of time. It was through him that I discovered how to install software from source and that there was a veritable treasure trove of cool desktops to install. That led me to AfterStep. I remember it being a serious challenge to install (completely from source), but once it was up and running, it became my digital canvas for which I would spend the next few years creating desktop art. At one point I had just about everything on the desktop displaying some level of transparency and anyone who happened to check out my computer would gaze in wonder at what I'd created. They were jealous. They wanted what I had.

It was, in a word, impressive.

My run with AfterStep lasted a few good years, until I discovered Enlightenment. It was then that I realized I could have the cool aesthetics with the addition of a bit more functionality. Enlightenment E16 was a more cohesive desktop that seemed to be better aware of itself than anything else I'd used. It was also highly configurable, which made for many a late-night tweaking session.

Enlightenment remained my desktop of choice for a very long time. Sure, I toyed around with the likes of Blackbox and Windowmaker, but they were so minimal and offered even less cohesion than what I'd been using. At that point, I couldn't afford to take a step backward. I knew too much to settle.

And then Compiz came into the mix and changed everything. At this point, Linux was the absolute ruler of eye candy on the desktop. With Compiz, it seemed there was nothing the Linux desktop couldn't do.

It was a magical time.

But then things took a turn for the serious. All of a sudden, I was a technical writer, covering Linux for TechRepublic (helping to build what would be called LinuxRepublic ... RIP). As much as I enjoyed spending hours tweaking the desktop, I had to focus on being more productive. During those early days, we Linux faithful were rather limited on the tools we had at our disposalat least when working within a decidedly Windows environment. I had StarOffice and Wordperfect and, for the most part, they served their purposes fairly well.

SEE: Rust: What developers need to know about this programming language (free PDF) (TechRepublic)

But the Linux desktop started showing its limitations. For example, when I was sent a file to read, I couldn't just save it to my Documents folder and double-click it to open. At that time most of the desktops simply weren't that aware. I had to open my word processor of choice and then open the file manually. Those extra steps were the norm.

Until a new desktop arrived on the market. Said desktop was GNOME. I remember meeting Miguel de Icaza at my first Linux convention at the Research Triangle. He was magnetic and passionate. I loved what he had to say and was anxious to try out this new desktop. It was 1999, and GNOME 1.0 was finally ready for public consumption. And I did consume. It was as though the developers took all the good bits from every window manager I'd used and rolled it into one. But even better, it was aware. Not in a singularity kind of way, but I could click on a file within the file manager and the appropriate application would open.

All of a sudden, I had eye candy and productivity! Life was good.

Of course, this was GNOME 1.0, so there were plenty of issues to deal with. Even so, I was a convert. I used GNOME for years (and still use it to this day).

Suffice it to say, no operating system desktop has evolved like Linux. Yes, you can compare the likes of Windows or macOS and say, "But look at how this changed!" Sure, the Windows and macOS desktops have evolved, but their evolution was a bit more subtle and didn't necessarily take the twists, turns and detours that Linux took to get where it is today. Nor did either of those operating systems offer the vast choice of desktops found with Linux.

The Linux desktop has morphed from an ugly, awkward, and less-than-productive state, to an almost avant-garde work of art, into an elegant, productive and professional environment. All the while, it offered more choices than most users had time to consider. Even today, I could go back to Enlightenment, or opt for the likes of Pantheon, Budgie, KDE, Openbox, Fluxbox, i3, Gala, Windowmaker or numerous other takes on the desktop.

So while the Linux desktop evolved into something efficient and elegant, it also retained a tight grasp on its roots. At this very moment, should I so choose, I could install one of the window managers that helped me learn about Linux back in the early days (although AfterStep hasn't been in development since 2013).

However, I'm quite content working with System76's COSMIC on top of GNOME. It offers everything I want and need from a desktop. And if I were to go back in time and look over the shoulder at a younger me, I would probably see someone who loved the desktop he was using, but wished it could be a bit more productive. I would then whisper into his ear and say, "Give it time."

To read more about Linux's 30th anniversary, see parts one and two of this series.

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The evolution of Linux on the desktop: Distributions are so much better today - TechRepublic

Mamama, dadada, bababa parents usually welcome with enthusiasm the sounds of a babys babble. Babbling is the first milestone when learning to speak. All typically developing infants babble, no matter which language theyre learning.

Speech, the oral output of language, requires precise control over the lips, tongue and jaw to produce one of the basic speech subunits: the syllable, like ba, da, ma. Babbling is characterized by universal features for example, repetition of syllables and use of rhythm. It lets an infant practice and playfully learn how to control their vocal apparatus to correctly produce the desired syllables.

More than anything else, language defines human nature. But its evolutionary origins have puzzled scientists for decades. Investigating the biological foundations of language across species as I do in bats is a promising way to gain insights into key features of human language.

Im a behavioral biologist who has spent many months of 10-hour days sitting in front of bat colonies in Panama and Costa Rica recording the animals vocalizations. My colleagues and I have found striking parallels between the babbling produced by these bat pups and that by human infants. Identifying a mammal that shares similar brain structure with human beings and is also capable of vocal imitation may help us understand the cognitive and neuromolecular foundations of vocal learning.

Scientists learned a great deal about vocal imitation and vocal development by studying songbirds. They are among the best-known vocal learners, and the learning process of young male songbirds shows interesting parallels to human speech development. Young male songbirds also practice their notes in a practice phase reminiscent of human infant babbling.

However, songbirds and people possess different vocal apparatus birds vocalize by using a syrinx, humans use a larynx and their brain architecture differs. So drawing direct conclusions from songbird research for humans is limited.

Luckily, in Central Americas tropical jungle, theres a mammal that engages in a very conspicuous vocal practice behavior that is strongly reminiscent of human infant babbling: the neotropical greater sac-winged bat, Saccopteryx bilineata. The pups of this small bat, dark-furred with two prominent white wavy stripes on the back, engage in daily babbling behavior during large parts of their development.

Greater sac-winged bats possess a large vocal repertoire that includes 25 distinct syllable types. A syllable is the smallest acoustic unit, defined as a sound surrounded by silence. These adult bats create multisyllabic vocalizations and two song types. The territorial song warns potential rivals that the owner is ready to defend their home turf, while the courtship song lets female bats know about a male bats fitness as a potential mate.

Of particular interest to me and my colleagues, the greater sac-winged bat is capable of vocal imitation the ability to learn a previously unknown sound from scratch by ear. It requires acoustic input, like human parents talking to their infants, or in the case of the greater sac-winged bat, adult males that sing.

The only other non-human mammal that scientists have documented babbling is the pygmy marmoset, a small South American primate species that is not capable of vocal imitation. The greater sac-winged bat offered the first possibility to study pup babbling in detail in a species that can imitate the vocalizations of others. But just how similar is bat babbling to human infant babbling?

To answer that question, I monitored the vocal development of wild pups in eight colonies. During the day, S. bilineata find shelter and protection in tree crevices and outer walls of buildings. Theyre very light-tolerant, and adults like to stay several centimeters apart from one another, making it easier for us to observe and record particular individuals.

To be able to recognize specific bats, I marked their forearms with colored plastic bands. I followed 20 pups from birth until weaning. Starting around 2.5 weeks of age, and continuing until weaning around 10 weeks old, pups babble away between sunrise and sunset in the day roost. Its very loud, audible even to the human ear because some babbled syllables are within our hearing range (others are too high for us to hear). For each pup, I recorded babbling bouts some of which lasted as long as 43 minutes and the accompanying behaviors throughout their entire development. In contrast, adult bats produce vocalizations that last no more than a few minutes.

Scientists have known for a while that pups learn how to sing by vocally imitating adult tutors while babbling. But our new study provides the first formal analysis that their babbling really does share many of the features that characterize babbling in human infants: duplication of syllables, use of rhythm and an early onset of the babbling phase during development.

Just as human infants produce sounds that are recognizable as what are called canonical adult syllables those with mature features that sound like what an adult speaker produces bat pups babbling consists of syllable precursors that are part of the adult vocal repertoire.

And just as human babbling includes what are probably playful sounds produced as the infant explores their voice, bat babbling includes so-called protosyllables that are only produced by pups.

Moreover, pup babbling is universal. Each pup, regardless of sex and regional origin, babbled during its development.

During my first field season, I noticed that during babble sequences, mothers and pups interacted behaviorally and vocally. Mothers produced a distinct call type directed at pups while babbling.

We humans alter our speech depending on whether we are addressing infants or adults. This infant-directed speech also known as motherese is a special form of social feedback for the vocalizing infant. Its characterized by universal features, including higher pitch, slower tempo and exaggerated intonation contours. The timbre the voice color also changes when people speak motherese compared to when talking to other adults. Timbre is what makes a voice sound a bit cold and harsh or warm and cozy. Could it be that female bats also changed their timbre, depending on whom they directed their calls to?

The results were clear: For the first time, wed found a non-human mammal that changes the color of voice depending on the addressee. Bats also use baby talk!

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Our results introduce the greater sac-winged bat as a promising candidate for cross-species comparisons about the evolution of human language. Babbling is like a behavioral readout of the ongoing vocal learning happening in the brain. When pups babble, they imitate the adult song and provide us with insight about when learning is taking place. It offers the unique possibility to study the genes that are involved in vocal imitation.

And since bats share their basic brain architecture with people, we can translate our research findings from bats to humans. Im fascinated that two mammal species that are so different share striking parallels in how they reach the same goal: to acquire a complex adult vocal repertoire namely, language.

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Bat pups babble and bat moms use baby talk, hinting at the evolution of human language - The Conversation US