Category Archives: Evolution

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Paolo UggettiESPN

The video that's been dubbed "45 Seconds of Madness" on YouTube doesn't quite tell the full story. The final 45 seconds of a 2018 high school game between Gonzaga and DeMatha was one of the most thrilling finishes to a game, any game, ever. Randy Trivers, who is still the head football coach at Gonzaga, can recall the sequence from that night as if he was watching it off the clip that now has over 500,000 views, including a play that didn't make the final cut.

In the video, Caleb Williams' heroics are on full display, but Trivers adds in the color that is missing. Gonzaga had gone down 20 points to DeMatha in the first quarter. What appeared to be a hopeless game turned into a comeback spearheaded by the then sophomore quarterback. Yet, with less than a minute left, Gonzaga still trailed by three points.

Williams needed to work some magic. The first escape was a third-and-33 that Williams had to convert after an offensive pass interference and a sack set them back. He shuffled around the pocket before dropping a downfield dart to his receiver. First down. A few plays later, an end zone fade gave Gonzaga its first lead of the night. It was short-lived -- DeMatha returned the ensuing kickoff for a touchdown, leaving Williams and Gonzaga only 15 seconds for a miracle.

The next play you see on the video is the game-winner -- a ridiculous Hail Mary attempt where Williams tosses the ball way up in the air and it finds a wide receiver. Pandemonium ensues.

But Trivers likes to talk about the play that came before. It's not in the video, but it's just as crucial. To even have a shot at the Hail Mary, Williams needed a chunk of yards and he needed them fast. So, he dropped back, hung in the pocket and hit a receiver streaking toward the sideline. The throw went for 15 yards, left four seconds on the clock and the stage was set for the game-winning prayer. To Trivers, that play (as well as the third-and-33) in that environment, with the Washington Catholic Athletic Conference championship on the line, embodies Williams.

"There are a lot of athletes that love to be in control and on top when it's favorable," Trivers said. "But when the odds are not with you, or the situation is sticky -- do you really want the ball? Do you really want the spotlight in that situation? When there's a high possibility of failing? Do you really want that? He's a guy that will genuinely take it every time."

It's often difficult to remember that Williams is still a teenager. He won't turn 20 until the day before USC faces off against UCLA this season in November. It's also hard to grasp that, between last season at Oklahoma and this year at USC, Williams has only started in 12 regular-season games in his entire college career.

"I've played alright, I feel like I can play better" Williams said this week when asked to assess his performance through six games. "I don't feel like I've unlocked everything that I can do. I'm trying to get to that point because this team needs my best."

As USC (6-0) heads to Salt Lake City for what will be one of the tougher games this season against Utah (4-2), Williams has looked and played the part of a veteran quarterback. It's what has helped facilitate the transition of Lincoln Riley's offense from Oklahoma to USC, and it's what has allowed everyone from the left tackle who has been on the team for five seasons to the new star wide receiver to trust him to lead a team with immediate College Football Playoff aspirations.

AS PATRICK MAHOMES scurried away from a Tampa Bay Buccaneers defender, spun gracefully to avoid another and then tear-dropped a jump pass into the hands of Kansas City Chiefs running back Clyde Edwards-Helaire after traveling 39.4 yards a few weeks ago, Williams was watching.

"I thought it was awesome," Williams said of the play. "And I said, 'I can do that too.'"

It should come as no surprise to those who have watched him play that Williams watches and takes after Mahomes. Through six games, Williams has extended plays better than almost any other quarterback in the nation. According to ESPN Stats and Info research, Williams is averaging four seconds before a pass when pressured. Among quarterbacks with at least 30 such pass attempts, that is the fifth-longest average in all of college football.

"That's the kind of player he is," Riley said. "That's great if the pocket is clean all day. That's fine. But I mean, in modern day college football, that doesn't happen very often. It doesn't happen in the pros much either. That's why you're seeing an influx of guys who give you that ability and can make things happen."

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Williams isn't exactly a running quarterback (he's thrown for 1,590 yards and ran for 178 so far), but when necessary, he doesn't hesitate to do so. This season, he's looked confident taking off with his legs when the play calls for it, while also defibrillating plays when the pocket collapses and he seems on his way to being sacked.

"Sometimes you have to improvise," Williams said. As a kid, he was on the smaller side, so he had to find ways to gain an advantage on those bigger than him. "That was always kind of one of my things ... I'd just kind of duck under or duck under the legs or anything like that so yeah, I'd say I take a little pride in it."

For the linemen who protect him and the skill players who surround him, learning about Williams' propensity to keep plays alive keeps them on their toes. Literally.

"At this point, it's like black magic," running back Travis Dye said. "I turn around and it looks like he's about to be sacked and he Houdini's out of it. He can make a bad situation look just phenomenal. He's Johnny Football without all the mess."

"With him, you gotta keep going or you might miss a play," tight end Malcolm Epps said. Epps credits part of Williams' ability to avoid getting tackled and keep his legs moving to his work in the weight room. "Y'all don't see him in the weight room, he lifts, he lifts like the rest of us not like other quarterbacks, he lifts."

Like many other great college football players, Williams' skill, work ethic and talent are undeniable, but how he applies those qualities is where he stands out.

"What you need in that position is this steadfast confidence," Trivers said. "And you could sense it in him, you know, the way he moved, the way he walked, the way he showed guys that he was willing to prepare and work."

As Trivers points out, Williams has never been a "rah-rah" guy, but rather through poise in pressurized situations and a short-term memory when things go awry, Williams motivates in a more subdued manner that projects assertiveness.

That confidence shows in the way he approaches everything from pass rushes to interviews, to the weightlifting Epps mentioned, to the way he connects with his teammates and really, anyone in his orbit. Trivers describes it as a unique charisma that creates a "magnetic, gravitational pull." Riley calls it a "great feel for people."

That much was evident to even the average viewer who tuned in to watch Oklahoma once Williams entered the game against Texas as a replacement for Spencer Rattler last season. The Sooners promptly made a 21-point comeback and won the game. Talk to the teammates he now has at USC, and there's no shortage of singing Williams' praises when it comes to his leadership, which began in earnest as soon as Williams arrived on campus. Once players understood what kind of offensive plan Riley and Williams were bringing to the table, the buy-in was automatic.

"It makes you want to do better, it makes you want to be better," Dye said of watching Williams in Riley's offense. "It makes you want to be more perfect."

For wide receiver and reigning Biletnikoff winner Jordan Addison, who transferred to USC at least in part because of Williams (both are from the Washington D.C. area), the appeal of playing with Williams was rooted in the fact that he knew Williams would get him the ball. Once they talked, he also knew he and Williams would connect off the field.

"You know how sometimes you can just read someone, you can tell that they're being real," Addison said. "That's him, so that's just kind of how that went. And I just trusted him with [all of] it."

WHEN WILLIAMS WAS still in high school, former Gonzaga High and Stanford quarterback Kevin Hogan would show up from time to time to throw the ball and throw with Williams. At that point, Hogan had been bouncing around the NFL for a few years.

"If you didn't know which one was who and you just watched the ball come out," Trivers said, "You wouldn't really know, 'Oh man, that's definitely the NFL guy and that's definitely the high school guy,' You wouldn't know it."

Though Williams has often come off as a natural, the development of his talent has always been in the hands of someone who realized what kind of potential he had. Trivers took it upon himself to maximize Williams in his offense, and after four years, that responsibility has fallen to Riley, who succeeded in doing that to the point where Williams packed up his bags and followed him 1,400 miles west to try to build on what they started.

As Hal Mumme pointed out a few weeks ago, the trust between quarterback and coach is at the crux of what makes the Air Raid great. For Riley, whose track record with quarterbacks has been as good as anyone's, that has rung even more true with Williams.

"It's definitely more ideal," Riley said of building his relationship with Williams from his true freshman season to his second year. "It helps you plan. You can start to project how people are going to play with him, how you want to play, how does that fit his skill set?"

The year-to-year advantage is clear, but when you're trying to transition an entire offense into a different program, having continuity between coach and quarterback creates an invaluable trust. As Riley pointed out earlier this season, what the two have gone through -- both at Oklahoma and in making the jump to USC -- over the past calendar year has only strengthened their communication and connection.

"I trust him completely," Riley said. "There's not anything that's offensive that we wouldn't do or wouldn't call with him. ... I don't worry about, 'This is gonna confuse him,' or 'Is this gonna slow him down?' He can handle it now."

This week, Riley was asked about his relationship with one of his former quarterbacks -- Jalen Hurts. Hurts, who now plays in the NFL for the Philadelphia Eagles, transferred from Alabama to Oklahoma where he became a Heisman Trophy finalist under Riley. The former Sooner smiled when talking about what he thought of their time together.

"Maybe more than anything, we got him to loosen up a little bit. Got him to relax," Riley said of Hurts. "Jalen is a pretty serious, stoic guy, and then coming out of the program that he did, there's a little bit of a different approach. [We] allowed him to be able to relax, play the game maybe a little bit more free flowing."

While it may have been an adjustment for Hurts to go from Alabama to Riley's Oklahoma team, contrasting that with Williams helps to understand why the two work together so well. Williams is already a loose guy, a relaxed but driven personality who embraces the free-flowing aspects of Riley's version of the Air Raid. And in Year Two of their partnership, they have almost created a separate language for themselves -- including gestures, hand motions and even whistles -- only they can understand.

"We kind of communicate really fast when I'm on the field, and he's on the sideline, just thinking through plays and things like that," Williams said earlier this season. "Sometimes I'll call the play, he likes it, he'll give me the shoulders or give me a thumbs up, which means go ahead. So it's a lot more trust, and a lot more flexibility."

Their relationship has evolved to the point where Riley said he knows almost right away, between Williams' mannerisms and such, what kind of day he's going to have. When going over film from the previous week's games, it doesn't take many words for them to know exactly what the other will want to focus on or fix for the following week. The two now seemingly live on the same page.

"There's just like a deeper understanding of what we're doing," Riley said. "Because of that, he's playing with a lot more confidence."

And because of Williams' place on the team, not just as a quarterback but as a leader, that has meant that the entire team is, too.

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The evolution of Caleb Williams and the instant remaking of USC into a contender - ESPN

[P/Fe] vs [Fe/H] for stars in our sample (shown in red) with their respective stellar population represented by different symbols (thin disk circle, thick disk inverted triangle and halo, s-rich diamond). Arcturus, for which P is determined from higher resolution atlas spectrum (Hinkle et al. 1995) is indicated by the black star symbol. P abundance determinations (all scaled to the solar abundance used in this work: A(P) = 5.36 and A(Fe) = 7.45) from multiple literature sources are also plotted in gray (giants in black) and represented by different symbols. In dashed line we show the chemical evolution trend in Cescutti et al. (2012) resulting from core collapse supernova (type II) of massive stars with the P yields from Kobayashi et al. (2006) arbitrarily increased by a factor of 2.75

Phosphorus (P) is considered to be one of the key elements for life, making it an important element to look for in the abundance analysis of spectra of stellar systems.

Yet, there exists only a handful of spectroscopic studies to estimate the P abundances and investigate its trend across a range of metallicities. We have observed full HK band spectra at a spectral resolving power of R=45,000 with IGRINS instrument. Abundances are determined using SME in combination with 1D MARCS stellar atmosphere models. The investigated sample of stars have reliable stellar parameters estimated using optical FIES spectra (GILD; Jnsson et al. in prep.).

In order to determine the P abundances from the 16482.92 Angstrom P line, we take special care of the CO(=74) blend. We determine the C, N, O abundances from atomic carbon and a range of non-blended molecular lines (CO, CN, OH) which are aplenty in the H band region of K giant stars, assuring an appropriate modelling of the blending CO(=74) line. We present [P/Fe] vs [Fe/H] trend for 38 K giant stars in the metallicity range of -1.2 dex < [Fe/H] < 0.4 dex. We find that our trend matches well with the compiled literature sample of prominently dwarf stars and limited number of giant stars.

Our trend is found to be higher by 0.05 0.1 dex compared to the theoretical chemical evolution trend in Cescutti et al. 2012 resulting from core collapse supernova (type II) of massive stars with the P yields from Kobayashi et al. (2006) arbitrarily increased by a factor of 2.75. Thus the enhancement factor might need to be 0.05 0.1 dex higher to match our trend. We also find an empirically determined primary behaviour for phosphorus. Furthermore, the phosphorus abundance is found to be elevated by 0.6 0.9 dex in two metal poor s-enriched stars compared to the theoretical chemical evolution trend.

G. Nandakumar (1), N. Ryde (1), M. Montelius (2), B. Thorsbro (3), H. Jnsson (4), G. Mace (5) (1)Lund Observatory, Department of Astronomy, Theoretical Physics, Lund University, Box 43, SE-221 00 Lund, Sweden, (2)Kapteyn Astronomical Institute, University of Groningen, Landleven 12, NL-9747 AD Groningen, the Netherlands, (3)Department of Astronomy, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan, (4)Materials Science, Applied Mathematics, Malm University, SE-205 06 Malm, Sweden, (5)Department of Astronomy, McDonald Observatory, The University of Texas, Austin, TX 78712, USA

Comments: 13 pages, 9 figures, accepted for publication in Astronomy and AstrophysicsSubjects: Solar and Stellar Astrophysics (astro-ph.SR); Astrophysics of Galaxies (astro-ph.GA)Cite as: arXiv:2210.04940 [astro-ph.SR] (or arXiv:2210.04940v1 [astro-ph.SR] for this version)https://doi.org/10.48550/arXiv.2210.04940Focus to learn moreSubmission historyFrom: Govind Nandakumar[v1] Mon, 10 Oct 2022 18:16:50 UTC (3,764 KB)https://arxiv.org/abs/2210.04940Astrobiology, Astrochemistry

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The Galactic Chemical Evolution Of Phosphorus Observed With IGRINS - Astrobiology - Astrobiology News

Though slime molds dont have neurons, these sophisticated single-celled organisms can solve mazes and merge into cooperative multicellular colonies. Photo: Ryan Hodnett/Wikimedia Commons, CC BY 2.0

Herschel Walker, the former football star-turned-US Senate candidate from Georgia, made headlines when he recently asked at a church-based campaign stop, if evolution is true, Why are there still apes?

This chestnut continues to be echoed by creationists, despite being definitively debunked. Anthropologists have repeatedly explained that modern humans did not evolve from apes; rather, both evolved from a shared ancestor that fossil and DNA evidence indicates lived 7 to 13 million years ago.

But Walkers question raises a larger, timely point that generally escapes recognition even by some scientists and educators.

A more fruitful query might be, If evolution is true, why are there still humans? Why is our species almost universally seen as the logical endpoint of evolution, with all other species serving as inferior detours or temporary placeholders on an inevitable march toward humanity?

This default, hard-to-shake view of evolution has been debunked as definitively as Walkers ape question. Yet it continues to be echoed in education, policy, business, conservation efforts, and the behaviors of the vast majority of people in Western, industrialised nations.

It is not necessarily surprising that non-scientists might see Earths history as a progression toward higher levels of complexity, with humans representing the most complex. What is startling is that traces of this view remain in scientific thought.

Biology teachers seldom realise it underlies lessons of four-chambered hearts succeeding over three-chambered hearts, or of simple urinary flame cells in flatworms and nephridia in earthworms next giving rise to kidney tubules in higher animals. As if humans are the benchmark by which all characteristics should be measured, and developing more human-like organs is a prime indicator of evolutionary advancement.

Worse, the progressive complexity view continues to infect anthropology. Its exemplified by the iconic march of progress a linear sequence of slumped apes eventually supplanted by upright humans. And it persists in the ideas that certain lower ancestral human populations gave rise to, and were succeeded by, more complex people, who are often depicted as having lighter skin tones.

People must unlearn this idea that biological diversity is an ascending ladder of complexity, with humans on top and nonhuman species as imperfect transitions and lesser beings. The chief result of this misguided worldview is our casual disregard for the natural environment, which via climate change, habitat destruction and biodiversity loss continues to have disastrous consequences for humans and nonhumans alike.

Microbes have always ruled the world

Humans are kin not only to apes but to every living thing. Like all other life forms, humans evolved from single-celled microbes. The last universal common ancestor (or LUCA) of all living things on Earth was a bacterium-like organism that arose around 4 billion years ago. All living species today are equally evolved from and similarly distant from that microbe.

Imagine a giant tree with a huge trunk, many large limbs spawning numerous branches, and a leaf on the end of each twig. Human beings represent just one leaf. Our long-gone extinct ancestors correspond to fallen leaves. Each leaf is a unique species. Each has traveled the same distance from the trees base or, put another way, from lifes bacterial origins to the present.

Science typically teaches that a Devonian Age of Fishes led to a Mesozoic Age of Reptiles, followed by a Cenozoic Age of Mammals culminating in our current Anthropocene, the Age of Humans. Yet as paleontologist Stephen Jay Gould argued in his 1996 book Full House, the apparent trend toward complexity is a bit of a mirage. Instead, Earth has remained, since life appeared, in an Age of Bacteria because of both their staggering abundance and overwhelming influence on all other organisms.

Consider that bacteria do countless things humans cannot, including orienting by magnetic fields, encysting to survive hundreds of years in suspended animation, and incorporating stray bits of DNA lying around their environment. Many bacteria make their own food by chemosynthesis or photosynthesis. Others glow in the dark, survive in anoxic muck or boiling water, or pick up metal particles to shield themselves from toxic and radioactive environments.

People remain dependent on simple bacteria to digest our food and produce vitamins in our gut things humans cant manage on our own. Microbes reign over the insides and outsides of our bodies. Their immense impact on human health both positive and negative is underestimated at our peril.

There are no higher or lower creatures

Naturalist Charles Darwin drafted a note to himself to never use the words higher or lower. Apes did not appear just so they could morph into humans. Nor did reptiles evolve solely to give rise to mammals, nor fish to amphibians.

Frogs are perfectly happy being frogs. They are not frustrated creatures thwarted from attaining humanity. Further, frogs have many adaptions humans lack. Can you sit underwater for hours on end, or propel your tongue out of your mouth? Frogs incompletely divided hearts are often seen as makeshift transitions, but they divert blood from their lungs to their skin, where frogs can gain sufficient oxygen to sustain their low metabolism while resting underwater. Traits people often view as imperfect instead enable other species to attain outcomes humans could never achieve.

But it is not simply frogs, bacteria, and apes that are considered less than in the typical evolutionary story. Even other hominins our closest ancestors get short shrift. After seeing endless march of progress memes, one might be forgiven for concluding that proto-humans existed on a straight and narrow path toward larger-bodied, bigger-brained hunters that directly replaced smaller, vegetarian ancestors. This is simply not true.

Robust herbivorous australopithecines, sometimes placed in the genus Paranthropus, continued to exist for at least a million or more years after smaller meat-eaters in the genus Homo appeared. Archaic Homo species did not disappear just as anatomically modern humans appeared, and Neanderthals had brains that were on average larger than those of our more gracile species.

Anthropologists studying genetic diversity have learned how fragile humanity is: During multiple population bottlenecks, our ancestors came within a hairs breadth of extinction. Life has never been about attaining humanity. Humans evolved as a result of chance contingencies and random mutations.

As Gould famously argued in his 1989 book Wonderful Life, if evolutions tape were to be rolled back, humans might not reappear. The world would surely be different if humans had never evolved, but frogs and butterflies might be better off, especially given humanitys frequent disregard for the welfare of Earth and its inhabitants.

No one doubts human beings are special indeed unique. After all, people are (to our knowledge) the only ones pondering evolution, not to mention creating symphonies and skyscrapers. Still, that is not saying much: All species are unique, or else they would not be distinct species in their own right. Each species can do things humans only dream of, whether flying or diving deep under the sea.

Truly, who is to say that butterflies or dolphins are not more evolved than us?

The rise (and fall?) of Anthropocentrism

Perhaps these inaccurate views of inevitable progress arose in large part because of the bizarre current circumstance in which Homo sapiens is the sole hominin left standing a condition entirely unlike most of human and pre-human history.

People naturally think categorically and are primed to see differences rather than similarities between humans and other animals. Further, numerous studies show that people are instinctively teleological tending to see goal-driven progress everywhere, starting at a very young age. This universal tendency is independent of culture and strong even among scientists, although it is undoubtedly reinforced by cultural conditioning.

In particular, this view of our species as the crowning achievement and inexorable culmination of Earth history is a product of Western philosophical and religious tradition, tracing more to Aristotle than to Australopithecus. Many people underestimate the extent to which this view has both fueled and been fueled by Judeo-Christian faiths and Western scientific sensibilities. Platos essentialism (with its emphasis on perfect versus imperfect forms) and Aristotles scala naturae (a hierarchical classification system for animals) are the bedrock underlying the Western anthropocentric worldview.

As Western culture overtakes and threatens to eradicate many Indigenous cultures, people living in industrialised societies often fail to see that anthropocentrism is merely one way of seeing the world. Religions such as Jainism and Buddhism are less anthropocentric than Abrahamic faith traditions. But they are still less ecocentric than philosophical Taoism, and most Native American and Aboriginal worldviews, which typically put all life on a level playing field.

In numerous Indigenous cultures, humanity does not exist on an elevated platform from which it looks down on other species. There is modesty and equity. There is appreciation and gratitude for all of nature rather than a sense that nature exists solely for humanitys benefit, to use and squander as it sees fit (or perhaps does not see, failing to use the illustrious foresight for which H. sapiens is typically celebrated).

Reimagining the march of progress

The march of progress view wrongly implies that nature, having successfully arrived at humanity, can stop its mission. It implies that evolution inexorably ends with us. But anthropology teaches that evolution continues apace, with H. sapiens as likely to continue evolving as every other species that survives to see another day.

So, perhaps the best retort to Herschel Walker and like-minded people is to wonder why, if evolution is true, humans do not live up to our potential. Why do all people not fully use their impressive brains and touted foresight? Why do they not accept and embrace science? Why do some sneer down on other species as lesser or lower? Why do they not care for all living things?

In this age of the Anthropocene, as H. sapiens puts its heavy and indelible stamp on every last corner of the globe, humanity must continue to evolve, in outlook most of all. All peoples must learn to accept what science clearly shows: that ours is simply one among many extraordinary species, and that humanity must be seen as a part of not apart from nature.

Ours may be a singular species, but ours is also a singular planet, the only one known to support precious life. To ensure that humanitys fascinating story does not end tragically, all people should tell this story not with hubris but with humility.

This work first appeared on Sapiens under a CC BY-ND 4.0 license. Read the original here.

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The Problems of Evolution as a March of Progress - The Wire Science

Shark evolution has been in motion for hundreds of millions of years, with around 500 species now swimming the oceans. Although sharks are under more and more pressure, mainly from human activity such as hunting, their history shows they are able to adapt rapidly to environmental changes. This flexibility in shark evolution could be a benefit in the midst of climate change, which is already causing problems for many ocean dwellers who lack this adaptability.

Factoring just how long theyve been around, some people may wonder are sharks dinosaurs?

According to Live Science, sharks have hunted through the oceans for around 450 million years, while dinosaurs only arrived around 240 million years ago. Furthermore, dinosaurs mostly didnt survive the many extinction events that sharks survived (albeit in reduced numbers). Despite their primordial and sinister appearance (thanks Jaws!), theyre not even close relatives. A Harvard news article notes that chickens, ostriches and alligators still remain the closest relatives to Tyrannosaurus rex.

The Natural History Museum of London describes how the golden age for sharks arrived pre-dinosaur times, roughly 359 million years ago. At the time, sharks dominated the oceans following a mass extinction event that wiped out a lot of their competitors. CNN notes that these animals were actually the first vertebrate predators on the planet, firmly ahead of dinosaur activity.

Sharks are difficult to follow through the fossil record. Unlike dinosaurs, sharks have a cartilaginous skeleton rather than being made up of solid bone. Unfortunately, this structure doesnt fossilize well because it doesnt calcify. So, finding evidence of shark species throughout the ages is mostly limited to teeth and skin scales, which contain calcifying minerals such as calcium and bioapatite.

In fact, examining these denticle microfossils showed evidence of an extinction that wiped out around 90% of sharks 19 million years ago. Not only did open ocean populations of sharks disappear, but the species also became less diverse, according to a study published in Science.

Occasionally, an entire skeletal remnant is fossilized. On discovery, this can tell paleontologists a lot about ancient sharks. For example, a single fossilized vertebral column helped scientists determine the age and size at birth of the mighty Megalodon.

From the fossil evidence available, scientists have been able to piece together some of the phases of shark evolution and see how each phase has helped sharks remain a top predator.

For example, being cartilaginous makes sharks relatively lightweight, which helps them conserve energy while swimming long distances. Tapered bodies and well-placed fins coupled with dermal denticles and tail fins that are larger at the top make swimming itself much more efficient and powerful. This means that sharks can undertake long migrations and swim at speed. As a result, they have few natural predators apart from humans.

They are also generalists, able to occupy a variety of ocean niches, and their teeth have evolved to cope with a broad flexibility in diet. For example, fossil evidence shows that, during the early Jurassic period, sharks developed a flexible, protruding jaw. This helped them tackle larger prey and eat animals bigger than themselves.

Sharks are optimal hunters with a lateral line sensory system that senses vibration from prey in the water. They also have the ability to pick up on electromagnetic fields which helps not only with food location but also with navigation.

Sharks also survived the Paleocene-Eocene Thermal Maximum, which saw a dramatic rise in both global carbon dioxide and temperature around 56 million years ago. Their continued survival can likely be credited to their ability to rapidly adapt to environmental change. For example, a rise in water temperature causes a rapid reduction in shark body size over the relatively short evolutionary period of 7,000 years. Certain shark species are also able to move between salt and fresh water with ease.

New shark species continue to be discovered, both ancient animals in the fossil record and contemporary sharks swimming the oceans today.

For example, closer examination of an encased plaster specimen held by the Canadian Fossil Discovery Centre in Manitoba introduced the world to Dave finally freed after 40 years in the archive. At around 15 feet in length, not only is Dave one of the largest fossilized shark specimens in the world, but he also might be a new species never seen before.

Closer examination of a 20-year-old fossil in storage has also revealed a new ancient shark species coming from the shallow primordial seas near the United Kingdom. SciTech Daily reports that the evidence comes from the teeth of this extremely rare shark skeleton fossil.

New species swimming around in todays oceans continue to be discovered, too. For example, Smithsonian Magazine describes a new glowing kitefin discovered in the ocean depths around New Zealand. Meanwhile, the number of sixgill saw shark species increased to three this January after two new species of this ancient lineage were discovered off eastern Africa, each showing the typical and rather odd arrangement that Pop Sci describes as long, flat snouts studded with teeth. Sawsharks use their chainsaw-like snouts to dice their prey into ribbons before dining, in case you were wondering the purpose of a nose studded with teeth.

Check out Northrop Grumman career opportunities to see how you can participate in this fascinating time of discovery in science, technology, and engineering.

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Shark Evolution Through the Millennia - Now. Powered by Northrop Grumman.

Changes in the size and organization of the brain distinguish the emergence of modern humans, but we know little about the genetic basis of these changes. Researchers in the Netherlands have now combined large-scale neuroimaging and genomics data to identify genetic variants associated with anatomy and development of the human brain.

One feature that distinguishes the human brain from those of monkeys and apes is its size. Each hemisphere of the human cerebral cortex has a surface area of approximately 1,840 cm2, compared to approximately 600 cm2 for the chimpanzee, our closest living relative. Analyses of endocasts suggest that the cortical surface of Homo sapiens is dramatically expanded, and is shaped differently, compared to extinct hominin species.

These changes were likely accompanied by alterations in white matter tracts, the brains long-range connections. Together, they may have contributed to the emergence of language and other complex cognitive skills.

Gkberk Alagz of the Max Planck Institute for Psycholinguistics in Nijmegen tried to confirm the results of a recent study that identified genetic variants associated with expansion of the human cerebral cortex, by examining brain scanning and genomics data from nearly 19,000 individuals, held at the UK Biobank.Their analyses failed to replicate the earlier findings. But the results suggest this may be because, while functions such as language usually depend on circuits that are localized within one brain hemisphere, the earlier study relied on measures that were averaged across both hemispheres.

With this in mind, Alagz and his colleagues examined neuroimaging and genetic datasets from more than 30,000 individuals, focusing on 33 measures of regional and global surface area, and looking at each hemisphere separately. They also looked at diffusion MRI data to examine 48 different white matter tracts.

This large-scale neuroimaging genomics approach enabled them to identify genetic variants associated with the surface area of multiple brain regions and with the long-range connections both within and between the left and right hemispheres of the brain.

Their analyses revealed that certain gene regulatory sequences associated with the surface area of left hemisphere speech and language regions are enriched in the developing human brain.They also discovered that genetic variants also found in Neanderthals made a far smaller contribution to connectivity of the left uncinate fasciculus, a white matter tract that connects the frontal lobe to the temporal lobe and is involved in language.

The findings, which are published in the Proceedings of the National Academy of Sciences, suggest that evolution of the human brain involved a gain of regulatory genetic elements in the genome. These enhancers become active in the fetal human brain and function to influence the activity of genes that contribute to the surface area of the cortex, one of these being ZIC4, which is implicated in neurogenesis, or the production of new brain cells.

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Genetics linked to evolution of bigger human brain size - Big Think

Social media is awash with disgusting medical-themed videos involving everything from doctors popping pimples to extracting ingrown hairs. But what can explain the popularity of these gut-churning clips and why do so many people love watching them so much?

These videos can rack up thousands, hundreds of thousands or even millions of views. One of the most well-known channels, Dr. Pimple Popper, has more than 15 million followers on TikTok, and over 2 billion views on YouTube.

One clip posted to TikTok in June, 2021, with the caption "Happy Sunday" shows a spot slowly being squeezed with an extractor tool. It has since been viewed almost 65 million times.

This kind of footage regularly provokes a feeling of disgust, which is generally thought to be a negative emotion. According to Daniel Kelly, a professor in the Department of Philosophy at Purdue University, and the author of Yuck!: The Nature and Moral Significance of Disgust, this emotion evolved to primarily protect us from two thingspotentially poisonous foods and contagious diseases.

"The emotion took on other functions on top of those as humans got more socially complex, and can be triggered by moral violations linked with 'purity' or by members of out-groups that are seen as far down the social hierarchy," Kelly told Newsweek.

The disgust that people feel after watching these kinds of videos is probably linked to the fact that the emotion evolved to help us avoid contracting a disease or becoming contaminated with an infection.

"It's a component of our pre-emptive behavioral immune system, as it were," Kelly said. "But since we can't directly perceive most of the things that make us sickbacteria, viruses, other kinds of microbeswe tend to be sensitive and alert to more easily perceivable indicators, especially signs that someone else is less than fully healthy, and so might transmit their unhealthiness to us if we get to close."

"The most common signs are other people who are obviously sick, sneezing, sweating, coughing, outbreaks of sores or other skin aberrations. So that's what disgust is on the 'look out' forit's those kinds of cues that it tends to be very sensitive to. Falling within this category are the kinds of cysts and pimples and other things that are center-stage in a lot of these videos."

The popping of cysts, pimples and other similar bodily abnormalities, are particular triggers of disgust because this act leads to the release of bodily fluids.

"Bodily fluids, especially bodily fluids that have left the bodyblood, spit, sexual fluids, waste products and other excretionsare some of the most universal and potent triggers of disgust there are," Kelly said. "Not coincidentally, they're also some of the most robust vectors of disease transmission."

"What happens to someone who is experiencing the emotion of disgust is multi-faceted," Kelly said, "You make that yuck face, you tend to think of the disgusting thing as contaminated and contaminating, polluted, you get that flash of nausea and emotional frissonbut you also tend to keep an eye on, keep track of, whatever it is that triggered your disgust."

So if watching gross medical videos disgusts us, why do so many people love watching them, while many others cannot bear the sight of such clips? According to Kelly, the answer is, again, multi-faceted.

"There's the general thrill of catharsis and living vicariously through someone else, of which this is just a specific instancewhatever is satisfying about these sorts of phenomena when they happen to us, we get a sort of paler shadow of the same satisfaction when we see it happening to someone else," he said.

Disgusting things are also very good at attracting and capturing our attention, perhaps not surprisingly given the evolutionary role of the emotion.

"It's just part of the way the psychological system works, how it's able to do its job well," Kelly said. "I think that adds to why these videos tend to get so many hitswatching triggers this psychological system, and not only do you get to live vicariously and what something that is intrinsically interesting, but you get a little charge of emotion, the experience itself has a little bit of voltage."

According to Kelly, the valence, or subjective value, of the disgusting event may be aversive, but only slightly. He compares watching these kinds of videos to the way that some people seek out feelings with negative valence in small doses, such as eating spicy foods, which can cause pain, or going for a run, which can produce a burning sensation in the muscles.

Another reason people may seek out these kinds of videos is that is a chance to have an interesting experience without actually being exposed to the risks and dangers that disgust evolved to protect us against.

"You're seeing the stuff through a screennot only can you turn it off whenever you want, or look away, but you're not at all at risk of being infected with anything," Kelly said. "There's a prophylactic effect, and I think that allows people to more safely indulge the experience. It's similar in a lot of ways to how people like to go on roller coasters or bungie jumpyou get the thrill, voltage, and experience of the feeling of hurling towards your death, but really you are quite safe.

"Likewise with, say, horror moviesyou get to experience intense fear, but you're not really about to be killed by a axe murderer or turned into a zombie. It's sort of an emotional freebieditto with the disgust people feel with these pimple videos."

Val Curtis, director of the Environmental Health Group at the London School of Hygiene and Tropical Medicine, said seeking out these kinds of experiences may have an evolutionary basis.

"If you're a small primate, it's really important to learn thingsto learn what's frightening, to learn what's disgusting," Curtis told the BBC. "We all seek out opportunities to learnand that's called play."

"It's similar to the fear response. We're attracted to roller coasters, for example, because it's really nasty and scary, but you learn what it is to be frightened. We all have a drive to play, and try out things safely. You're practising to see what happens."

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TikTok's Obsession with Pimple Popping Has Deep Roots in Evolution - Newsweek

The magical early hours of the October hunting and fishing day are cherished by any and all sportspersons and many other outdoor folks who enjoy a simple nature agenda. The sunrise is slow to rise and form shadows as the fog lifts from the silently traveled forest wildlife trails, where rabbits, raccoons, coyotes, deer and other critters traverse from their feeding areas to secret resting zones each day. This weeks rainfall along the waterways has turned the meandering main flows of Lake Erie tributary streams from babbling brooks to rambling creeks and rivers, with fresh runs of steelhead and brown trout. These fish have left the deep waters of Lake Erie and Lake Ontario far offshore. They now use their olfactory sense of smell to relocate to the waterways where they were born or stocked to reproduce and continue the cycle of life for these cold water species.

The full moon last week started the first cycle wave for many forms of fish and wildlife where the strong reproductive instincts of their species are initiated. If you are an angler not ready to hang up the rod and reel yet, this is one time of the season when the steelhead and brown trout are running upstream in all the Lake Erie tribs. In the Lake Ontario tribs, especially the more significant streams like the lower Niagara River, Oak Orchard Creek and farther east, the Salmon River, now is the time to cash in on the fun of big fish.

In big numbers, the giant King Salmon are running in the Salmon River near Altmar and Pulaski. Shore anglers wading the river in chest-high waders have a chance to catch fish that weigh 10 to 30 pounds and more. Last week, a local angler, Mathew Nardolillo, was fishing with friends while visiting Waters Edge Fish Camp Lodging near the river. Using his Lamiglass X-11 rod with Pfluger President XT reel, he was set up with 20-pound Berkley Big Game monofilament main line and Berkley 14-pound Vanish fluorocarbon leader. To the leader, he attached a size 6 hook with a Death Roe 8mm glass bead for bait. This team of friends scored big on King Salmon. Nardolillo shares humble secrets the group discovered. He says, We had never fished this river before and it was a learning process for us. We did not use any floats because it was too crowded with other anglers to do that, but we kept adjusting our drift to just tick along the bottom where the fish were. We would cast out to 10 oclock and have enough weight on to just tick the bottom at 12 oclock, then raise the rod to avoid snagging the bottom at 2 oclock and try it again. You needed to pick a section of the stream and do that and repeat. Thats fishing! At Waters Edge Lodging, this is their first year catering to anglers; call Polly Dieckman at 973-903-2344 for info.

With the NYS early big game archery season underway since Oct.1, whitetail deer hunters are well positioned to score on venison for table fare in the next several weeks. The incredibly well-developed olfactory sense of smell among the whitetail deer species allows bucks to locate does ready to breed as the ritual of reproduction begins at this time of year. This ridiculous deer sense of smell begets hunters to take note of the wind direction before heading out to their hunting area. Swirling wind patterns often trigger deer to sense man nearby, raise their awareness level of danger and turn to walk the other way, often frustrating hunters. The bright white deer hair of bucks and does is often the only thing a deer hunter will see when this happens. Hence, the reason these deer are called whitetail deer. For deer hunters with years of research and hunting experience, science has educated the group to understand that humans have a good sense of smell. Still, deer have an olfactory sense 300 times more sensitive than people. They can smell things that we cannot. Sometimes, this keen olfactory sense of the deer can lead them astray too. Savvy hunters in NYS are not allowed to bait deer with corn or apples on the ground, but hunters are allowed to use scent attraction formulas to raise the interest of deer to come and investigate. Deer are curious critters. A single apple cut in half and placed on a broken stick-out branch next to the hunter can act as a human cover scent, providing an attractive aroma for a favorite food for deer to locate and munch on. While deer in rut, in their breeding cycle, are usually not interested in eating at all, they are more interested in finding a mate, and right now. Immediacy is paramount for the bucks that sleep very little during the mating season. Understanding this part of the buck cycle, note that it is interesting that in NYS, it is legal to use bottled scents of does ready to breed and bucks looking for a doe. Each of these parts of the olfactory scent world of deer hunting allows the advantage to hunters, it seems. Yet when using these scents in the woods, it is surprising how often a hunter will see a deer coming toward him because of these triggers to follow scents.

The olfactory supremacy of the deer can also smell the hunters human scent and steers away. Advantage: deer. This is why many hunters set up their stand downwind of a deer trail, then drag an attractant scent on a dragline as they walk from the deer trail to their downwind stand placement. The deer will not smell the hunter whose scent is blowing away, while the nose of the deer is down to the ground following the fresh drag scent left by the hunter traveling to the stand with the string. Advantage: hunter. These are some things hunters do during this part of the hunting season. If you are a hunter, know that this is the fun part of the year and a time when using just arrows and strings, it is possible to attract a deer close enough for a harvest of organic, fat-free meat for the next several months. Wishing the best of luck to all archery hunters!

Wishing everyone healthy and safe fun at home and in the outdoors! God bless America.

Outdoors Calendar:

Oct. 1 Nov. 18: NYS Big Game Early Archery Season, hunting allowed 30 minutes before sunrise to 30 minutes after sunset.

Oct. 15-28 NYS autumn turkey hunting season, hunting allowed sunrise to sunset, fall season bag limit: 1 bird of either sex.

NOTE: Submit Calendar items to nugdor@yahoo.com at least 2-weeks in advance.

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Rod, Gun & Game: Season of evolution begins in the autumn outdoors - Springvillejournal

NEW YORK, N.Y. - Today Verizon announced the formation of a new, enterprise wide, shared services organization, advancing their strategy for 2023.

Chief Administrative Officer and General Counsel, Craig Silliman, will be taking on a new role leading the company's new central support services operations, as President, Verizon Global Services (VGS). Craig and VGS will be responsible for most shared services teams within Verizon including Real Estate, Sourcing, Supply Chain, Fleet, Finance Operations, Global Technology Solutions, Reporting and Insights, Learning and Development, Public Policy and Information Security. Craig and VGS also will be responsible for bringing a holistic approach to Verizons partner ecosystem, which consists of tens of thousands of vendors providing services to the company, to ensure seamless and efficient business processes.

In announcing these changes today, Verizon Chairman and CEO Hans Vestberg said, This is a logical evolution of our strategy. These moves will accelerate our efforts to drive efficiencies, enabling us to reinvest savings in network superiority and customer growth.

Verizon will discuss the economic benefits of establishing Verizon Global Services in its 3Q earnings communications on October 21.

Craig Silliman brings the experience of seeing the entire Verizon business from his current CAO role, as well as an increasingly critical role navigating the past few unprecedented years. Hans and the board have repeatedly called on Craig to tackle the companys most strategic and difficult challenges, from Work from Home mobilization to supply chain to spectrum and other acquisitions to various strategic negotiations.

Over the past 2 plus years, under unprecedented circumstances, weve learned a lot about how we deliver our services to customers. Vestberg added, It has given us new insight and unlocked a number of new opportunities. VGS will enable us to consolidate what weve learned and scale it for the entire organization.

As Craig steps into this new role, effective immediately, Vandana Venkatesh, will assume his responsibilities as Chief Legal Officer. In this new role, Vandana will report to Hans Vestberg and lead the company's legal, privacy, and corporate security functions. Vandana is currently SVP and General Counsel for the Verizon Consumer Group (VCG). She has led a variety of leadership roles in the company supporting Enterprise, Public Sector, Information Technology, and Sourcing business units.

"Vandana is a proven leader with extensive experience across a variety of legal functions and business units, said Vestberg, and will be a key member of our leadership team during this transformative time.

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Verizon announces organization evolution to accelerate efficiency and growth - Verizon

Calling all Kardashian-Jenner style watchers: something has shifted in Kendall Jenners workout wardrobe. The model has been wearing Adidass retro-tinged Samba trainers on and off all year, pairing them with maxi skirts and straight-leg jeans as well as her gym gear. But to join BFF Hailey Bieber for a Pilates class this week, Jenner chose another classic sneaker: the Nike Air VaporMax Plus.

Nike Air VaporMax Plus sneakers

Kendalls black trainers were first unveiled in 2017, at the time the latest iteration of the game-changing Air Max 1, which hit the market in 1987 and went on to rule the 90s and Noughties with every new release. Dropping 30 years after the birth of the Nike Air Max, the VaporMax was the first of the trainers to have an entirely air bubble sole. Jenners Nikes are nothing if not practical, but like her Sambas, theyre a sneakerhead-approved legacy shoea fact this style-conscious super will be only too aware of.

Getty Images

They werent the only retro touch to her post-workout look. That long-sleeved crop top pushed up to reveal a matching sports bra underneath is simultaneously evoking early Britney Spears, crop-top queen Jennifer Lopez in her On the 6 era, and Jessica Albas dance teacher wardrobe in the 2003 classic Honey.

The finishing touch that makes it quintessentially Kendall? The leather tote bag slung over her shoulder. When youre one of the most in-demand models on the circuitnot to mention a scion of the first family of reality televisionyou dont chuck your gym gear into any old polyester duffel bag. Kendall Jenner keeps her towel in the Park tote by The Rowyours for $1,790.

The Row Park 3 medium leather tote

Alo Yoga Airbrush leggings

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Kendall Jenners Chunky Trainers Are the Evolution of a Noughties Classic - Vogue

Over the last couple of months researchers tracking emerging SARS-CoV-2 variants have started noticing something strange. No one new variant has looked like taking over but instead a variety of different subvariants seemed to be accumulating the same mutations.

These mutations all seemed to be converging in a way to evade our pre-existing immunity, and a striking study recently appeared speculating the virus has the potential to completely escape our current immune responses. As many people around the world return to normality, deeming the pandemic over, these new evolutionary signals suggest we may be done with thinking about COVID but SARS-CoV-2 is most certainly not done with us

Twitter has been described by some as a town-square, analogous to a massive open space where anyone can offer their two cents on anything. But in practice its actually nothing like that. A more apt analogy would be Twitter resembles a massive apartment building filled with countless rooms devoted to conversations between people with shared interests or beliefs.

Inside one small room in the gargantuan Twitter high rise resides a diverse assortment of virologists, infectious disease researchers, epidemiologists, data visualization nerds, and ambitious armchair experts. They all focus on one particular subject tracking the genetic mutations of SARS-CoV-2.

Wading into the world of Variant Tracking Twitter can be dizzying for the uninitiated. A whirlwind of dense terminology accompany tweets filled with graphs tracking coded mutations and increasingly complicated variant names. Pango lineages, GISAID data, Nextstrain clades.

In September a word started popping up frequently amongst the coded conversations citing RBD mutations in K444T and N460K. That word was "convergence."

For the last two years the evolution of SARS-CoV-2 has been strange, to say the least. Across 2020 experts frequently warned of the potential for this novel coronavirus to mutate, but initially, it remained remarkably unchanged until a trio of variants emerged late in the year.

Alpha, Beta and Gamma all suddenly popped up. Three different lineages, in three different parts of the world. All with relatively similar mutations.

The changes had begun and in 2021 we saw a series of infection waves cross the world, each one driven by a new variant. Alpha leading to Delta leading to Omicron. What was particularly unusual about these successive waves was each subsequent variant was different from the one that preceded it. This wasnt the case of a single lineage slowly mutating and changing but big evolutionary leaps were taking place, with new lineages coming out of nowhere.

Since Omicron hit in late 2021 and early 2022 the path of the pandemic seems to have changed. Instead of big evolutionary leaps the Omicron lineage has splintered into scores of different subvariants.

Omicron first emerged with three relatively independent arms (BA.1, BA.2 and BA.3) but now the lineage features a head-spinning array of subtypes. And since the recent BA.5 wave no single subvariant seems to be dominating. Instead, researchers are watching all these different subvariants slowly start to take similar shape, with the same mutations appearing to be successful across multiple independent evolutionary pathways.

In the world of evolutionary biology the theory of convergent evolution explains how completely unrelated organisms can separately evolve incredibly similar traits. When faced with the same selection pressures distinctly different organisms can often end up with fascinating similarities.

One of the most commonly cited examples of convergent evolution is the striking similarity between shark and dolphin bodies. These two organisms share no common ancestor yet they evolved to look alike based on facing the same selection pressures.

In terms of SARS-CoV-2, many of us may be familiar with the hearing about the viruss unique spike protein. Its the highly identifiable protein that our successful vaccines use to generate protective immune responses. One part of the spike protein is known as the receptor binding domain (RBD). It sits at the top of the protein and helps the virus attach to certain receptors in human cells, a crucial process for infection and replication in our bodies.

Our original vaccines, using a version of the 2020 Wuhan coronavirus spike, are still incredibly effective against current Omicron variants with many mutations because until now there have been very few changes to the RBD.

A recent study, available as a preprint and yet to be peer-reviewed or published in a journal, presented a striking set of data suggesting a number of new Omicron subvariants are all appearing with similar mutations on the receptor binding domain. In an email to New Atlas, corresponding author on the paper Yunlong Cao explained the similar mutations across multiple independent variants indicates SARS-CoV-2 is successfully finding ways to evade our current immunity.

RBD convergent evolution, means that the RBD mutations evolved by the recently emerged SARS-CoV-2 Omicron lineages converge on the same sites (hotspots), including R346, K444, V445, G446, N450, L452, N460, F486, F490, and R493, Cao explained. Seeing this convergent evolution pattern would mean that SARS-CoV-2 would evolve immune-evasive mutations much more frequently than before, and the resulting new variants would be much more immune-evasive.

In mid-September the first draft of the study by Cao and his colleagues was published on a preprint server. At the same time, in a serendipitous case of research convergence, variant trackers on Twitter were simultaneously reporting similar findings.

One researcher dubbed it The Great Convergence, as variant trackers consistently reported finding similar mutations across drastically different subvariants. As an example of convergent evolution, it seemed SARS-CoV-2 was finding certain mutations universally successful.

Marc Johnson, a microbiologist from the University of Missouri, was among the first variant-tracking Twitter researchers to begin visually graphing these cases of convergent evolution. He is one of the few researchers to be completely unsurprised by the mutations starting to appear in subvariants around the world. In fact, he had seen exactly these same mutations over a year ago.

For the past 18 months Johnson has been obsessed with tracking what are called cryptic lineages. These are extremely rare, distinctive forms of SARS-CoV-2 with massive suites of mutations not seen in any circulating variant.

The work starts with wastewater, tracking traces of virus variants detected in sewage samples around the world. The current hypothesis Johnson is working with is these cryptic lineages are the result of long-term COVID infections, the virus primarily persisting in a persons gut.

What we think is happening is that there's these patients that can't clear the infection, Johnson explained in an interview with New Atlas. And the virus, because there's no bottlenecks from spreading from person to person, it just hits the evolutionary fast forward button. And it's evolving way faster than the circulating lineages.

Johnson is clear that he doesnt believe these cryptic lineages are anything to be concerned about from a circulation perspective. For the most part, the viral fragments he is picking up in wastewater are inactive. So it's unlikely these cryptic lineages will seed the next major variant.

Instead, these cryptic lineages offer a kind of perfect mutational laboratory, allowing Johnson insights into the potentialities of SARS-CoV-2. His obsessive characterizations of cryptic lineages over the past year and a half has resulted in him being completely unsurprised every time a novel mutation appears in a circulating variant.

Not only had he previously seen the mutations that appeared late last year in Omicron, but hed been waiting for these new convergent mutations currently discussed to finally appear in circulating variants.

When Omicron arrived, I'm like, check, check, check, check, check, check, check, Johnson said. All 11 of them were mutations I had seen before, but then some of the ones that I had seen a lot before that were not in Omicron were 452, 460, 346 the big ones now that it's finally picking up. So for about a year, I've been saying when is it going to pick up these other two mutations?

Around the same time Cao published his preprint study, Johnson posted a graph on Twitter trying to map out the most common convergent lineages. Within days a relatively simple visual depiction of convergent lineages had become a kaleidoscopic mess of connections. Resembling one of those pinboards you see amateur detectives in movies use to connect clues in a crime, the convergent lineages being followed by variant trackers on Twitter were moving fast. Every day new lines were being connected as different sub variants converged on the same mutations.

So its clear a number of different SARS-CoV-2 subvariants seem to be converging on the same mutations, but what does that mean? If these particular mutations are offering the virus growth advantages, helping it slip past our immune defenses, how is that happening?

This was the question Yunlong Cao and colleagues wanted to answer. In a preprint described as a tour-de-force set of deep mutational scanning experiments, the researchers probed thousands of antibodies isolated from vaccinated people who experienced breakthrough COVID infections.

The goal was to understand what kind of immunity exists in a person who had been vaccinated and subsequently infected with Omicron subvariants BA.2 or BA.5. The million-dollar-question: As the virus drifts away from its original 2020 form, are we concurrently developing immunity to its newer iterations?

Caos study discusses a 60-year-old theory known as original antigenic sin. Back in 1960 an epidemiologist named Thomas Francis was studying the historical ebbs and flows of influenza epidemics.

Francis suggested the bodys first exposure to a pathogen can leave a permanent immune imprint, or memory. This "original sin" can hinder our ability to fight that same pathogen if that pathogen begins to change its shape and become less recognizable.

Subsequent research since the 1960s has somewhat validated the idea of original antigenic sin. When we are young and our immune system faces a new pathogen for the first time our naive B cells learn to produce the right seek-and-destroy antibodies.

That initial encounter creates memory B cells. These immune cells can exist for decades, patrolling the body on the hunt for that same pathogen. This is how our immune system can quickly respond to future infections.

But the problem with this technique is that the immune system tends to lean on these memory B cells and not learn how to recognize newer versions of pathogens as they slowly evolve. For the immune system, near-enough is good-enough as long as the original imprint still somewhat recognizes newer shapes of pathogenic invaders.

One of the crucial findings in Caos study was that when a vaccinated person experiences a breakthrough Omicron infection they primarily recruit memory B cells to produce antibodies. In fact, according to the study, 80% of the B cell response to Omicron breakthrough infections are existing vaccine-induced memory cells.

Generally this is a good thing. It is why the original vaccine with the 2020 spike protein still offers good protection from Omicron. It's also why many vaccinated people who have experienced an Omicron breakthrough infection likely faced a relatively mild disease. But crucially it means our immune systems may not be learning how to recognize newer Omicron subvariants.

The advantage of this [memory B cell response], and the reason why our body evolved to behave like this, is that when infected with Omicron, our body could rapidly generate antibodies against the new antigen through memory B cell recall, not depending on eliciting antibodies through naive B cell maturation which is slow, Cao explained to New Atlas. However, the bad part is that infection with Omicron would not very effectively broaden the breadth of our neutralizing antibody repertoire since our immune system majorly reuses the memory B cells elicited by [original] vaccination.

The next part of Caos study has perhaps been the most contentious amongst COVID researchers, as more hyperbolically inclined commentators have inferred apocalyptic outcomes. Here, the scientists looked at the specific mutations that many subvariants seem to be converging upon right now. These mutation hotspots seem to be converging on the RBD of the coronavirus spike. And these are the spots our previous memory B cell antibodies were targeting to protect us from Omicron infections.

This is how the virus is mutating to evade our immune defenses.

So the scientists set out to model what future mutational pathways the virus could hypothetically take to evade our current antibodies. Adding just six specific mutations to BA.5 was found to be enough to evade most current RBD antibodies.

And most significantly, several subvariants have already been detected with some of these mutations. Subvariants BQ.1.1 and XBB in particular were found to be the most immune evasive, escaping even Omicron-specific antibodies.

What happens from here is decidedly unclear. Immunologist Menno van Zelm has studied ideas of immune memory and original antigenic sin. He said its still an open question whether immune imprinting is a lifelong thing or whether immune responses can evolve alongside a virus.

We've been very happy to show that immune memory after effects can last for a long time, explained van Helm. But it could bite us now that after years, you still have that memory and that memory could still outcompete any new responses. We honestly don't know. And it might be a balance, right? Because as soon as you don't have enough response anymore, it means that you generate completely new responses, and then your memory will not outcompete.

Van Helm is also clear to stress our immune responses are complex and multi-faceted. Caos research focuses solely on memory B cells and the antibody responses generated. These immune responses do govern basic levels of transmission and infection but plenty of other factors influence how severely sick we become from an infection.

We have our T cells, van Helm added, referring to the main immune cells that kill and clear most pathogens. Many people have, since they've been vaccinated, also been infected. So they have responses of T cells and B cells to other parts of the virus. So we're not completely naive, as we were back in 2020. And I think that is part of why the disease severity is much lower now.

Cao is a little more wary of the potential increase in disease severity from these new converging subvariants. He speculates it is possible T-cell responses are maintained in the face of these new RBD mutations, as those immune cells can target more conserved parts of the virus that have yet to shape-shift. But Cao also speculated there's potential for a future iteration of the virus that can completely evade antibody neutralization, cause high rates of infection, and generate severe disease in some people.

T-cell response could make some contribution to preventing severe symptoms and deaths, Cao said. However, they do not efficiently prevent infection and transmission; otherwise, there would not be the BA.5 wave after BA.2. [And] it is possible that [new variants] cause more severe symptoms, as vaccines and the previous infection would not provide humoral immunity protection, both from the memory B cell level and sera neutralization.

Both Cao and van Helm do agree that current variant-specific vaccines may not be the most optimal path forward but they are certainly the best solution we currently have. Despite evidence of original antigenic sin there is also strong evidence that boosters are beneficial in lowering risk of serious disease.

Nevertheless, the pandemic certainly isnt over and scientists are still racing to keep vaccines and therapeutics ahead of where the virus is going. One suggestion from van Helm to potentially bypass the problem of original antigenic sin is to create a new vaccine designed to evade current memory B cell responses and generate a whole new immune imprint.

It might be worth by taking only the parts of the protein that are new, and vaccinating only with that, so that you only generate a new response, van Helm speculated. And that will then be in addition to the original memory that you have towards the wild type virus.

And while those scientists work on the next generation of therapeutics, the variant trackers are still obsessively following the rapid viral mutations in granular detail.

In the past, new pandemic waves had been easy to identify. A single variant emerges and genomic testing around the globe quickly shows it growing in prevalence. But now, with the dramatic fragmentation of Omicron into dozens of subvariants, new trends are harder to detect.

A number of variant trackers have recently shifted their surveillance tactics to try and get a better grasp on emerging waves. Instead of setting their systems to follow specific variants some are now grouping together variants with convergent mutations. By rolling variants with shared mutations into similar buckets it quickly becomes evident that these new SARS-CoV-2 iterations are becoming prevalent.

Cornelius Roemer, a viral evolution researcher based in Europe, has been at the forefront of chronicling the global growth of these new convergent variants. His monitoring has shown the more key RBD mutations in a subvariant, the faster its growth.

Roemers tracking suggests subvariants with four key RBD mutations may account for more than 30% of new viral samples up to the end of September. But add another two to three key RBD mutations and you see some extraordinary new subvariants (XBB, BQ.1.1 or BA.2.3.20) emerging and growing at rapid rates.

Where this is all going is anyones guess. Will one of these subvariants ultimately dominate as in previous waves? Or will we face what some have referred to as a "variant soup," with several similar subvariants becoming prevalent in different parts of the world?

Marc Johnson describes the current emerging wave as more like a rising tide, and as all these subvariants converge on the same mutations we will see rising caseloads. And he says the rate of the virus mutating is ridiculously fast.

From his work with cryptic lineages Johnson suggests the virus still has a lot of room to move in terms of potential space to mutate. Whether that means it becomes more or less severe is unknown, but with such a massive volume of ongoing infections allowing new mutations to flourish Johnson expects to see plenty more novel lineages appearing in the future.

I mean, people say whens it going to reach the optimum, like it's a moving target. It depends what immunity its up against. It will just keep adapting to it. It might go full circle one day, who knows?

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As Omicron mutates wildly the virus shows first signs of convergent evolution - New Atlas