In 1953, Donn Fichter, a graduate student at Northwestern University in Chicago, had a simple transportation idea: What if you tipped an elevator on its side, enabling it to run horizontally, and set it loose in a city? Unlike conventional urban mass transit, elevators are responsive to individuals, callable with the push of a button, and not subject to schedules. 

After completing his dissertation in 1958, “Automated Urban Circulation,” Fichter spent years turning that idea into a complete transit system design he called Veyar. At its core, Veyar would offer small automated cars running on lightweight guideways. The electric cars would be available at any hour and travel directly from origin to destination without stops, schedules, or drivers. “Personalized transit,” he called it, in which each car “is a self-operating vehicle which can go unattended.” To keep infrastructure construction costs low, he explained, “they have to utilize existing public right of way: the streets.” Fichter self-published the design in 1964, calling it “Individualized Automatic Transit and the City.”

For 60 years, personalized transit systems like Veyar gained support from generation after generation of transportation engineers, but none were ever built. That’s because personal rapid transit systems demanded infrastructure cities couldn’t afford and automation technology that didn’t yet exist. What finally solved both problems wasn’t a transit agency or a federal program, but rather the autonomous vehicle industry. Companies like Zoox and Waymo built Fichter’s system more practically, starting with the automation and letting existing streets serve as the guideways.

The origins of personal rapid transit

Donn Fichter was born in Minneapolis in 1926. After serving in the Army during World War II, he earned engineering degrees from Brown and Northwestern. He was the first serious advocate of what urban planners would eventually call personal rapid transit, or PRT—a vision of on-demand, automated, point-to-point city travel. 

Fichter conceived Veyar at a time when traffic choked American cities. Cars gave riders individual freedom at the expense of gridlock. Buses, subways, and elevated rails offered more efficiency but subjected riders to fixed schedules and routes. 

What no one had yet built, Fichter argued, was a third system that combined the automobile’s spontaneity and the subway’s separation from traffic, available to anyone at any hour without a driver, a schedule, or a transfer. Gridlock notwithstanding, the environmental stakes, he believed, made the solution urgent. 

Even before the first Earth Day was celebrated in 1970, Fichter foresaw the “ecological imperative” to reduce our dependence on private automobiles. He made this case explicitly in a 1968 PRT planning paper, “Small Car Automatic Transit.” Fichter claimed that small, electrically-propelled, autonomous cars running on guideways would mean cleaner air, quieter streets, and cities less congested with the machinery of driving and parking.

Personal rapid transit systems catch on in the 1970s

“Your car is waiting,” wrote journalist Paul Wahl in a 1971 Popular Science feature on personal rapid transit systems. “On entering the car, you push a button to select your destination, then take a seat. The cabin is roomy, automobile-like in accommodations.” 

Wahl went on to describe how a PRT trip might unfold: “The automatic vehicle moves away on the station spur, accelerating until it enters the stream of traffic on the guideway.” The car would then switch off the guideway at its destination spur, “with a central computer doing the driving.” 

The experience Wahl described was precisely what Fichter’s Veyar system proposed. Small electric cars—sized for just a few riders—would run on slender elevated tramways threaded along existing streets. Stations every few blocks would keep cars queued and ready. Just like an elevator, a rider would board, close the door, press a button, and go. The car would merge into mainline traffic automatically, travel nonstop to the destination, and pull itself into the arrival station without further instruction. Then it would wait, callable for whoever needed it next. A computer would control the entire network. What the elevator had done for the skyscraper, Veyar would do for the city.

The federal bet on personal rapid transit begins with the Nixon administration

By the early 1970s, the idea attracted serious attention. As Wahl wrote, experts were “banking on it to relieve our metropolitan areas from the twin stranglehold of pollution and congestion.” The federal government committed $6 million to build and demonstrate four competing PRT systems at Transpo72, an international transportation exposition held at Washington, D.C.’s Dulles International Airport in 1972. One of those prototypes was destined for a small college town in West Virginia, where West Virginia University needed a better way to move students between its multiple campuses and downtown Morgantown, West Virginia. 

At the same time, planners in Minnesota began drawing up blueprints for a city to be built from scratch on 50,000 acres of rural land—a place called the Minnesota Experimental City, or MXC. The new city was the brainchild of Athelstan Spilhaus, a polymath University of Minnesota dean who had already helped design the 1962 Seattle World’s Fair and co-invented submarine warfare instruments. Spilhaus wanted MXC to be a living laboratory, not a utopia, and personal rapid transit was to be its arteries. 

The federal commitment to PRT in the early 1970s produced a brief but remarkable flurry of competing designs. Engineers at aerospace firms, university labs, and automotive companies developed more than two dozen distinct guideway systems—Monocab, TTI, Dashaveyor, Cabinentaxi, Aramis, staRRcar, and others—each with its own switching designs, propulsion method, and structural approach. No two were compatible. The proliferation reflected a significant engineering problem—no one had cracked the code on the automated control systems required to make PRT work. Wahl called this control system the “super-robot trainmaster.”

“The heart of any personal rapid transit system,” Wahl wrote, “is the central computer facility that runs things efficiently and economically, making it practical.”  He described a fully autonomous system that not only controls all the cars, “but also handles vehicle distribution and scheduling.” In fact, the central computer would manage just about everything, he explained, leaving little to human operators who are prone to make mistakes. Unfortunately, at the time, such sophisticated automation technology did not exist. 

Besides lacking the necessary automation, PRT systems demanded infrastructure cities couldn’t afford to build at scale, even with available federal funding. A network of lightweight guideways would need to be built above city streets, with stations every few blocks, for PRT to deliver on its promise. By the mid-1970s, federal funding had dried up, Transpo72 had come and gone without producing a single municipal contract, the Minnesota Experimental City project had been canceled, and PRT’s moment of official enthusiasm had passed—with one notable exception.

America’s first and only personal rapid transit system

The West Virginia University Personal Rapid Transit system, which opened in Morgantown in 1975, became the closest thing to a guideway-based automated transit system ever built for regular urban use in the United States. It connects the university’s three campuses and the downtown central business district via 8.7 miles of dedicated guideway and five stations, carrying riders in small electric vehicles on demand, without stops between origin and destination. And most importantly: The system works. 

Since its debut in 1975 WVU’s personal rapid transit system has logged more than 100 million trips, using electric vehicles that carry roughly 12,000 passengers a day during the school year. Despite its impressive track record, Morgantown also illustrated the trap at the heart of every PRT proposal. The project ran wildly over budget—partly because engineers rushed to meet a politically mandated deadline tied to the Nixon administration—and the cost per rider was never remotely competitive with conventional mass transit. 

More fundamentally, Morgantown succeeded because it was built for a specific, constrained geography: a university town with four fixed nodes and a captive ridership. That configuration bears almost no resemblance to the open-city, go-anywhere network with stops every few blocks that Fichter had imagined, and it offers no blueprint for replication in a traditional urban setting. For a major city to build what Fichter described, it would have had to retrofit onto automobile-centric city streets dozens or even hundreds of miles of elevated guideway. It’s something no city has ever tried.

Driverless cars: PRT without the tracks?

And yet, six decades after Donn Fichter sketched his first Veyar pods, you can summon one of their descendants with your phone. Today, Waymo operates driverless electric vehicles across six major American cities, completing nearly half a million rides per week in 2025. 

Amazon’s Zoox has deployed a uniquely designed robotaxi—no steering wheel, no pedals, carriage seating for four, bidirectional so it never needs to turn around—on the streets of San Francisco and Las Vegas. Between them and a growing field of competitors, the age of individualized automated transit has arrived—just not as anyone planned.

But do robotaxis really fit Fichter’s vision? A car can be summoned with the push of a button. It travels straight from origin to destination without stops. It is “a self-operating vehicle which can go unattended” as Fichter described Veyar in 1964. 

Fichter would recognize robotaxis instantly as personalized transit. What’s missing is the “rapid” promise of a PRT system. Driverless taxis are subject to the same traffic-choked congestion that has plagued American cities for nearly a century. 

In his 1964 specifications, Fichter worried that driverless vehicles “could not expect to share the streets with other motor vehicles,” which is why he proposed elevated guideways. Today, his concern seems prescient. 

Waymo has faced recalls for vehicles driving into flooded roadways, investigations into repeated failures to yield to school buses, incidents where robotaxis blocked emergency responders at active crime scenes, and acted as getaway cars. A citywide power outage in San Francisco in 2025 triggered a wave of vehicles simultaneously requesting remote confirmation checks, snarling traffic for hours. The riding experience remains geofenced to specific neighborhoods in specific cities. 

When issues arise, the system relies on remote human operators—Waymo employs about 70, half of them based in the Philippines—to step in. But these are engineering problems being worked through, not evidence the concept is broken. Arguably, city streets become the guideways when they are filled almost exclusively with robocars, which would complete Fichter’s vision in spirit, if not in intent.

But robotaxis were built as a for-profit product, not as civic infrastructure. They are privately owned, unevenly distributed in cities, expensive on a per-ride basis, and poorly regulated across most of the United States. 

What Fichter envisioned was a public system woven into the city—the way elevators are woven into buildings—affordable to everyone, and available at the push of a button. Waymo, Zoox, and their competitors have built something remarkable. But whether it someday resembles the civic infrastructure Fichter had in mind, or remains just another profit-based enterprise siphoning riders and revenue from transit agencies, is ultimately a policy question—one that cities and regulators have so far shown little urgency to answer.

In A Century in Motion, Popular Science revisits fascinating transportation stories from our archives, from hybrid cars to moving sidewalks, and explores how these inventions are re-emerging today in surprising ways.

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A treasure trove of prehistoric squirrel poop is painting a picture of a lost world. Some of the oldest DNA ever discovered and sequenced lies deep inside these ancient rodent droppings. That fossilized poop (or coprolite) is full of 700,000-year-old environmental DNA from numerous plants, insects, microbes, and large mammals that once lived in Canada’s Yukon, many of which are long gone. A study published today in the journal Nature Communications describes the findings.

A rodent time capsule

Arctic ground squirrels (Urocitellus parryii) are still alive today. They are widely found within Beringia, a region spanning the Yukon in Canada and Alaska in the United States. They are opportunistic feeders that eat a wide variety of plants, fungi, and insects. They will also eat meat, including dead flesh, whale meat, and even other rodents. They can also hibernate for up to seven months. Their wide diet and long-term hibernation in frozen burrows have helped create a detailed biological record of their environment.

“I’ve been describing them as acting a bit like tiny Arctic pack rats,” Tyler Murchie, a study co-author and McMaster University biomolecular archaeologist, tells Popular Science. “These squirrels are interesting both because of what they collected from the environment and because of their own evolutionary histories and how they adapted to the far north during previous glacial periods.”

The proof is in the poop

In the study, Murchie and his team analyzed 13 Arctic ground squirrel coprolite samples from the central Yukon. This research took place on the territory of the Tr’ondëk Hwëch’in First Nation and was conducted with permission. 

Compared to bones or sediments, fossilized feces like these coprolites are not used as often for DNA analysis since they can degrade more easily. However, the ground squirrel burrows in Arctic regions can remain frozen and sealed for thousands of years, preserving genetic material in the poop. The ground squirrel burrows here span several glacial periods, and the organic material inside can remain frozen and sealed for thousands of years. The samples in this study date back 30,000 to approximately 700,000 years ago and the biomolecules from ancient animals can be preserved in the coprolites.  

“Ancient squirrel poop was one of those ideas that sounded a bit ridiculous at first,” says Murchie. “Scott [Cocker, a study co-author] and I did it initially in part for fun and out of curiosity, not knowing what to expect. But scientifically, it made a lot of sense that these sorts of remains would be really information dense given how dense the burrows can be with macro-remains and given that they’ve been frozen continually for millenia. The squirrels were basically collecting pieces of the landscape and storing them in frozen burrows.”

To tell that something is coprolite, context matters. The scientists didn’t find a random poop pellet here or there, but found the droppings as part of a greater burrow system. 

“They are small pellets, roughly rabbit-dropping sized, and they look like dried or fossilized fecal pellets rather than random sediment clumps or plant fragments,” Murchie explains. “When you’re working with them though, they very much seem like frozen poop. When we subsample them and go to digest a portion to extract DNA, it smells like poop. So the organics are all still in there.”

Inside of these DNA samples they not only found smaller organisms like plants and microbes, but larger animals—woolly mammoths (Mammuthus primigenius), American cheetahs (Miracinonyx), horses (Equus), steppe bison (Bison priscus), and more. The team was able to reconstruct 18 mitochondrial genomes from the poop samples, including 12 ground squirrels, one hare, two bison, and three horses.

A humbling timeline

The team also found a previously unknown genetic diversity among Arctic ground squirrels, including one lineage that dates back 700,000 years. While this squirrel does not live in the Yukon, its relatives can be found in western Siberia.

“There’s something humbling in the timescale. Some of these samples are older than our species. Homo sapiens in our modern anatomical form are usually placed at around 300,000 years ago, and our oldest sample is roughly 700,000 years old,” says Murchie. “So these squirrels were living, collecting, eating, caching, and leaving behind these tiny biological archives long before humans like us existed.”

The team acknowledges that some of the DNA may have been picked up from the coprolite’s surface at a later time and species identification may be affected by incomplete genetic reference databases for animals that lived so long ago. However, these findings show that permafrost coprolites can be part of a high-resolution snapshot of prehistoric environments and complement more typical findings like bones and teeth. 

“Science is sometimes at its best when it takes something ordinary, weird, or even funny, and shows that it contains a much larger story,” says Murchie. “In this case, squirrel poop can turn out to be a window into deep time, climate change, extinction, evolution, and ecosystems that no longer exist.”

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Humans often announce the biological sex of their offspring before the baby even enters the world. For bald eagles, the process can take a bit longer. After nine weeks, Friends of Big Bear Valley (FOBBV) announced on Tuesday that Jackie and Shadow’s 2026 chicks are likely a boy and a girl.

The two chicks hatched in early April. Their names, Sandy and Luna, were bestowed on May 1. Now we know that Sandy is a female and Luna is male. Or at least we can confidentially guess. FOBBV, the non-profit who runs Jackie and Shadow’s 24/7 livecam, closely observed the duo since birth and noted traits that offered clues to the birds’ sexes.

“Male and female bald eagles have significant differences in vocal pitch; we have all heard the difference in vocals with Jackie and Shadow,” FOBBV wrote on Facebook. “Females are larger than males and so are their voice boxes (Syrinx), which results in deeper lower-pitched vocalizations We used frequency applications to record and analyze Sandy and Luna’s vocals and there were consistent differences in vocal pitch.”

FOBBV also notes that the only way to confirm Sandy and Luna’s sexes would be a blood test. But at 9 weeks old, the eaglets’ bone structure and foot pads have fully grown (and they can even see as well as their parents), so FOBBV can be confident in their assessment.

Jackie and Shadow’s 2026 babies: Everything you need to know

It’s been another roller coaster nesting season for Jackie and Shadow, a pair of internet-famous bald eagle parents living in San Bernardino National Forest in Southern California. After ravens destroyed two of their eggs in January, Jackie and Shadow laid two new eggs that successfully hatched.

Chick 1 hatched on April 4 at 9:33 p.m. PDT, while Chick 2 followed on April 5 at 8:30 a.m. PDT. Their large nest in Big Bear Valley east of Los Angeles is livestreamed 24 hours a day by nonprofit Friends of Big Bear Valley (FOBBV) and has captivated millions. 

On May 1, FOBBV announced the chicks’ names: Sandy and Luna. The names were selected by elementary school students after thousands of submissions from fans.

How long will the chicks stay in the nest? 

Chicks usually stay in the nest until 10 to 14 weeks of age. This year’s chicks will likely fledge sometime between mid-June and mid-July.

What challenges do the eaglets face?

Before leaving the nest, the chicks face threats from other birds of prey, including hawks, ravens, other eagles, and owls. Inclement weather can also present challenges for the chicks. In 2025, a March snowstorm resulted in the death of one of Jackie and Shadow’s three chicks.

During fledging, only 70 percent of eaglets survive. One of the greatest threats is from cars that can injure or kill the birds while they scavenge for food on roadkill. 

Who are Jackie and Shadow? 

The pair first got together in 2018 and successfully raised chicks in 2019 and 2022. However, their eggs failed to hatch in 2023 and 2024. Only 50 percent of eagle eggs successfully hatch, so this pair has already beaten the odds.

What happened to Jackie and Shadow’s 2025 eaglets?

In 2025, Jackie laid three eggs that all hatched in early March. On March 13, a strong snowstorm dumped up to two feet of snow and battered the nest with strong winds. Only two of the chicks were visible on the live cam when the storm passed by the next morning. FOBBV later confirmed the passing of one of the chicks. The two surviving chicks were later named Sunny and Gizmo after 54,000 names were submitted by fans.

What happens after chicks fledge? 

Young eagles usually fledge–or leave the nest and fly–when they can flatten their wings and have feathers capable of flight. This typically occurs when the birds hit 10 to 14 weeks of age. Males also tend to take their first flight a little sooner than females. So we might expect to see Luna take flight first.

According to FOBBV, fledglings from Southern California have been spotted as far south as Baja California, as far north as British Columbia, and as far east as Yellowstone National Park.

About 70 percent of bald eagles survive the fledgling stage. FOBBV does not tag their eagles, so it’s not possible to follow the chicks’ journeys after they flee the nest.

Can I help Jackie and Shadow?

Yes. Environmental groups are currently fundraising $10 million to protect Jackie and Shadow’s foraging area from development. Learn more at SaveMoonCamp.org.

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Today, NASA announced the four Artemis III astronauts and one backup crew member for the 2027 test flight. NASA astronaut Randy Bresnik will serve as the commander, alongside mission specialists Andre Douglas and Frank Rubio (also with NASA). European Space Agency (ESA) astronaut Luca Parmitano will serve as the mission’s pilot. 

Parmitano was selected to the ESA astronaut corps in May 2009 and is also a colonel and test pilot for the Italian Air Force. He is the first ESA astronaut assigned to an Artemis mission and immediately pointed to his family as motivation. 

“I am honored by the role that I have been given,” Parmitano said during the press conference. “The rocket figuratively and literally is NASA. I am grateful that NASA is allowing me to be part of this incredible group of people and this crew and for letting me fly. But we wouldn’t be going anywhere without fuel and the fuel that lets everything move is right here–Maia, Sarah, Marta, and my extended family here in the crowd. You are the energy that feeds my soul and your love is the spark that ignites every passion.”

Parmitano has already proven that he possesses coolness under pressure. On July 16, 2013, he nearly drowned during a space walk, after data about a previous spacesuit did not make its way up the International Space Station’s chain of command. Water chemistry issues caused a leak in the spacesuit’s cooling system. 

The issue started near the end of a spacewalk on July 9. At the time, the crew concluded that the water came from Parmitano’s drink bag. That initial assessment was incorrect. The leak occurred due to contamination build up that blocked a filter. The blockage allowed water to go into a line that feeds air to the astronaut’s helmet.

“When the water reached my face, it spread over my nose and up into my nostrils in an instant. I was almost blinded, I couldn’t hear anything and I couldn’t breathe through my nose,” Parmitano wrote in a March 2026 commentary on the event published in New Scientist. “I already knew I needed to reach the airlock and get back inside the International Space Station. The key question: how long did I have before the water reached my mouth and I couldn’t breathe at all?”

In a report released several months later, investigators said that ISS management should not have given the go ahead for the July 16 spacewalk following the incident on July 9. The report also criticized management for not immediately stopping the dangerous task as soon as Parmitano reported water in his helmet. The report ultimately included 49 recommendations to help prevent a similar incident.

Artemis III will undertake a series of challenging tests in Earth orbit in 2027. These tests are essential for Artemis IV in 2028, the first planned crewed mission to the lunar South Pole.

The agency’s Space Launch System (SLS) rocket will propel the Orion spacecraft and its crew from NASA’s Kennedy Space Center into low Earth orbit. After Orion systems checkout, the spacecraft will demonstrate rendezvous and test docking capabilities for the first time. It will use test versions from one, or both, American commercial human landing systems in development by Blue Origin and SpaceX. 

“This highly choreographed mission includes a dramatic multi-launch campaign of the world’s most powerful rockets, testing integrated hardware between Orion and the landers, including system interfaces, software, propulsion, and communications,” NASA writes. 

“Artemis III will push the boundaries of spacecraft operations in orbit. Luca’s assignment as pilot reflects the depth of European expertise in human spaceflight and draws on his extensive operational experience in high-pressure situations,” ESA’s director general Josef Aschbacher said in a statement. 

“At the same time, ESA’s European Service Module will once again provide the critical capabilities that power Orion, demonstrating Europe’s enduring role at the very heart of the Artemis program. The news out of Houston today is a powerful recognition of ESA’s role in enabling humanity’s return to the Moon – and a key advancement in our partnership with NASA. Europeans can take pride in being part of this exciting journey.”

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Archaeologists in Germany say a uniquely shaped ceramic vessel discovered inside a castle was potentially used for much more than simple distillations. According to the Saxony State Office for Archaeology, the over 1.5-foot-tall jug’s origins are “presumably” tied to medieval alchemy. But before anyone conjures images of magical rituals, experts say it’s far more likely the container’s creators intended the vessel for more grounded research trying to turn dull metals into gold.

Located in southern Saxony, Germany, Gnandstein Castle’s earliest iteration was built during the 13th century to overlook the Wyhra Valley. Generations of modifications eventually transformed the fortification into a manor, although many medieval architectural elements are still visible throughout the former residence. Gnandstein Castle received around a decade of renovations between 1994 and 2004, during which archeologists scoured the grounds for important historical relics.

More recent construction efforts took place in a previously demolished, 2,400-square-foot portion of the grounds. There, archaeologists found remnants of early modern brick paving and floor tiles dating to the early 16th century. But one additional artifact was particularly interesting—a glazed ceramic vessel with a rounded body, tapered neck, and three feet on the bottom, allowing it to stand upright. Its overall shape and design strongly suggest prolonged, controlled usage instead of storing liquids like wine or cooking oils.

Archaeologists suspect that the container was part of a larger distillation setup. Similar items from the era held liquid that was then heated from flames underneath it. After placing a rounded cap over the neck, vapors would transport up the neck and condense in the cooler top known as a helm or head. Final results frequently included plant extracts, mineral oils, medicines, and alcohol.

The Saxony State Office noted the artifact closely aligns to equipment used in “alchemical and proto-chemical practice” during the 15th and 16th centuries. Popular culture often depicts medieval alchemy as mystical pseudoscience, but a great deal of it actually forms the basis for present-day chemistry, pharmacy, and laboratory research. The ceramic relic itself supports this, as its creator likely chose the material knowing that metal containers sometimes release toxic or contaminating substances during various hot or acidic preparations. The Saxony region also had strong ties to mining and metallurgy around that time, further suggesting alchemical influences.

Unfortunately, the team cautioned that the object’s true use remains unclear. Researchers didn’t find any residual material inside the vessel, so there currently is no way of knowing what it once held. Despite the mystery, it’s now clear someone in Gnandstein Castle hoped to distill something—and possessed the equipment to accomplish it.

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Part of Dungeons and Dragons’ enduring charm is the game’s seemingly infinite possibilities. Players may start on a quest to slay a villainous dragon, only to spend hours of their campaign helping a local village deal with a vengeful necromancer. But no matter where the story goes, everyone’s choices are influenced by rolling a lot of dice.

The roleplaying game is particularly famous for its reliance on the 20-sided die, but there are all types of sizes depending on the situation. That said, the situations when someone might need to toss a 120-sided variant are few and far between. However, a collective of game designers called The Mint Tin Guys decided to make just such an accessory available for D&D fans. But why stop there? All those sides deserve some decorative flourishes, so the team recently debuted a unique, aluminum-crafted D120 die highlighting all 118 elements currently listed on the Periodic Table of Elements.

According to its creators, the elemental D120 is “perfect for tabletop RPGs, science classrooms, chemistry enthusiasts, or anyone who enjoys the fusion of geek culture and education.” It’s also a great way to bone up on the universe’s building blocks. Interested dice-throwers can head over to Etsy to snag one for about $150.

However, the designers took one small liberty.. At last count, the Periodic Table currently stands at 118 elements. The synthetically-created Oganesson was added to the reference table in 2002. With only 118 elements and a 120-sided die, two sides are essentially “wildcards,” but that adds to the overall charm. And with a 1-in-120 chance of landing on a non-element, the chances that you’ll encounter one of them often are pretty slim. Then again, anything is possible during a good D&D campaign.

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Evolution is responsible for Earth’s stunningly diverse spectrum of life, but that wasn’t always the case. In fact, the earliest eras of living organisms were comparatively boring. The earliest known animals date back about 635 million years (during the Ediacaran Period), yet they look remarkably similar to their descendents 96 million years later at the dawn of the Cambrian.

Why did evolution remain so stable for so long? It might be simply because Earth’s first creatures simply weren’t having much sex.

“Life was pretty nice during the Ediacaran, so the need for sex was rather limited,” Emily Mitchell, a paleozoologist at the University of Cambridge, explained in a statement. “There was relatively little competition, so there was no real pressure to change anything.”

Along with her colleague Andrea Manica, Mitchell recently combined spatial analysis and laser scanning with machine learning to analyze 574-million-year-old fossils excavated from southernmost Newfoundland’s Mistaken Point. Their findings, published today in the journal Nature Ecology & Evolution, show that the earliest animals’ reliance on asexual reproduction kept things largely uniform, and reduced the struggle for resources.

They offered Fractofusus as a prime example. At over 6.5 feet tall, the fern-like creatures dwarfed most of their oceanic relatives and likely lacked organs or mouths. They also absorbed food from the surrounding water while remaining anchored in place, reproducing through clones distributed by stolons or runners like present-day strawberry plants.

“If you’re connected to your neighbor by these runners, then you’re sharing nutrients and you don’t need to compete with them,” said Manica.

From there, the team constructed a machine learning model to approximate how Fractofusus and its fellow Ediacaran animals possibly behaved through varying reproductive strategies. The program’s neural network then identified simulations that aligned with known fossil record diversity patterns. Known as Approximate Bayesian Computation let them basically travel back in time to estimate how animals proliferated and squared off for limited resources.

They now believe the Ediacaran Period’s overall tranquility (and sexlessness) began to get complicated as species gradually migrated from deep waters to shallower regions. Once there, ancient animals endured new stressors like temperature swings, nutrient deficits, tides, and even storms. Life then adapted to face these increased threats—and left behind more fossils. The story they tell indicates that environmental stress often precedes a rise in sexual reproduction versus other methods of procreation. 

“When that happens, we can see a massive increase in dispersal distances as animals attempt to colonize new areas due to an increase in competition,” said Mitchell.

These shifting trends eventually ushered in what’s known as the Ediacaran “second wave” of animal evolution, which further amplified millions of years later during the Cambrian era, as animals started physically moving through their environments.

“If you’re suddenly in an environment where you’re essentially getting killed a couple of times per year, then that changes everything,” Mitchell explained.

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