Motivation is complicated. Psychologists define motivation as the desire or impetus to initiate and maintain a particular behavior. But sometimes, no matter how passionate you are about a goal or hobby, finding the motivation to actually do it can be difficult. Why is motivation so fickle? Explore intrinsic and extrinsic motivation, and dig into how these forces contribute to our drive. Directed by Magali García.

From its earliest incarnations, poker has always been a contest of guile, guts, and gambling. The game first emerged around 1800 in the melting pot of New Orleans, and soon spread up the Mississippi, Ohio, and Missouri rivers. So, how did this simple game of the American South skyrocket in popularity? James McManus shares how the card game became an international affair. Lesson by James McManus, directed by Chintis Lundgren.

In the 1930’s, a grand panda drama unfolded at the Chicago Zoo. Zookeepers procured a female panda named Mei Mei, and they were determined to find her a mate. They found a prospective suitor named Mei Lan, and the public eagerly awaited the patter of tiny panda paws. But the wait dragged on... and on. Why weren’t the bears breeding? Lucy Cooke shares common misperceptions about pandas. Lesson by Lucy Cooke, directed by Keegan Thornhill.

Rice contributes over 20% of the calories consumed by humans each year. Korean bibimbap, Nigerian jollof, Indian biryani, Spanish paella, and countless other culinary masterpieces all begin with rice. So how did this humble grain end up in so many cuisines? Carolyn Beans investigates the global expansion of this beloved crop and the unintended consequences of its popularity. Lesson by Carolyn Beans, directed by Na Na Na Studio.

Surveying his vast domain, Poseidon considers retirement. What if someone else donned the coral crown so he could spend his immortality harmonizing with whales and cozying up to hydrothermal vents? Poseidon decides he needs to prioritize himself for once. So, he summons his accountant and asks: how much could he sell the ocean for? Astrid J. Hsu conducts a financial analysis of our oceans’ worth. Lesson by Astrid J. Hsu, directed by Igor Coric, Artrake Studio.

Pharaoh Ramesses II reigned for almost 70 years in the 13th century BCE. He presided over a golden age of Egyptian prosperity, power, and wealth. But was he a model leader or a shameless egomaniac and master of propaganda? Jessica Tomkins puts this controversial figure on trial in History vs. Ramesses the Great. Lesson by Jessica Tomkins, directed by Brett Underhill, PorkchopBob Studio.

The question of whether or not humans are inherently selfish is one of philosophy’s oldest debates. The idea that we only act out of self-interest is an extreme stance that few philosophers would endorse. However, the idea that all humans have a deep selfish streak is something many philosophers would agree with. So, are we innately selfish? Mark Hopwood explores this classic conundrum. Lesson by Mark Hopwood, directed by Avi Ofer.

You might not guess it, but Alcon blue butterflies are just one of over 200 parasitic butterfly species, all of which target ants. And their offspring live highly unusual lives, tricking their way into ant colonies using mimicry. So, how do these butterflies do it— and why? Francesa Barbero explores the strategies caterpillars use to survive among ants on their journey to become butterflies. Lesson by Francesca Barbero, directed by Raghav Arumugam, Jagriti Khirwar.

Dodos are commonly considered brainless, blundering birds that were poorly adapted and doomed to die off, making their human-mediated extinction effortless and inevitable. But that’s not the case. So, what were dodos actually like? And what really caused their downfall? Leon Claessens uncovers the truth about these misunderstood and maligned creatures. Lesson by Leon Claessens, directed by Denys Spolitak.

Alcohol has been shown to have strange and selective effects on the brain. Many intoxicated people can perform complex tasks like holding a detailed conversation or navigating a walk home. Yet for those experiencing a blackout, the memory of these events is quickly forgotten. So, how does alcohol cause these memory lapses? Shannon Odell explores how ethanol interrupts the brain’s processes. Lesson by Shannon Odell, directed by Anton Bogaty.

Deep inside the Sumatran rainforest, a carrion fly descends, guided by the scent of its favorite place to lay eggs: rotting animal carcasses. But when it lands, it isn’t on liquifying flesh, but instead on the world’s biggest, and perhaps strangest, flower— Rafflesia arnoldii. So, how does this giant flower grow? Daniel Nickrent explores the parasitic tendencies of the foul-smelling plant. Lesson by Daniel Nickrent, directed by Igor Ćorić, Artrake Studio.

In 1947, India achieved independence from British rule — but this freedom came at a tremendous cost. Jawaharlal Nehru, India’s first Prime Minister, was eager to usher his country towards a brighter, united future. And one of the projects that would prove most essential to realizing this vision was the construction of Chandigarh. Vikramāditya Prakāsh details the creation of the futurist city. Lesson by Vikramāditya Prakāsh, directed by Jeff Le Bars, Jet Propulsion.

Long ago, the ancestral gods of Fiji settled on the Pacific archipelago. They eventually metamorphosed into various forms, with the god Dakuwaqa transforming into a shark. But he was unsatisfied. He became proud and greedy and wanted to establish himself as the mightiest god, and dominate all of Fiji’s islands. Raiana McKinney and Esther Wozniak share the tale of Dakuwaqa’s quest for power. Lesson by Raiana McKinney and Esther Wozniak, directed by KERO Animation.

In 1945, engineer Percy Spencer was standing near a RADAR device that produced high-intensity microwaves and noticed that his candy bar had melted. He then exposed popcorn kernels to the magnetron device, and sure enough, they popped. Soon after, the first microwave oven became available, using the very same technology. So, how does it work? Aaron Slepkov explores the science of microwave ovens. Lesson by Aaron Slepkov, directed by Yuriy Polyashko, Darvideo Animation Studio.

Suffering illness and despair, Chief Handsome Lake prepared for death. Then, he had a vision. He was walking through a planted field and heard a woman call out. She told him that the recent devastation had left her and her sisters with little hope for the future and asked if they could join him on his journey toward death. Who were these women? Rebecca Webster shares the tale of the Three Sisters. Lesson by Rebecca Webster, directed by Luisa Holanda.

In 1624, Mughal Emperor Jahangir received word of yet another defeat at the hands of his greatest enemy: Malik Ambar. Jahangir was so obsessed with defeating his rival, he commissioned a painting of himself shooting an arrow at Ambar’s skull. So, who was this brilliant tactician? And how did he come into power? Stephanie Honchell Smith shares Ambar's rise from enslaved youth to kingmaker. Lesson by Stephanie Honchell Smith, directed by Layron DeJarnette, Gumboyo.

Today is the annual wizard tournament featuring competitors from three schools, and you’re in charge. The wizards have entered the maze and compete in your chosen events in utmost secrecy; only you and they see what happens. But a dark wizard appears and casts a forgetting curse— throwing the results into question. Can you figure out who won the tournament? Alex Rosenthal shows how. Lesson by Alex Rosenthal, directed by Igor Coric, Artrake Studio.

On November 30th, 1935, dozens of writers passed away. They came from different backgrounds, espoused divergent beliefs, and wrote in a variety of styles. Yet almost 30,000 pages of their work was stashed in a trunk in an apartment in Lisbon, Portugal. So, what mysterious string tied all these writers together? Ilan Stavans explores the enigmatic life of Fernando Pessoa and his many identities. Lesson by Ilan Stavans, directed by Héloïse Dorsan-Rachet.

One day around 850 CE, a goatherd observed that his goats started acting abnormally after nibbling on some berries. The herder tried them himself, and soon enough, he was just as hyper. As the story goes, this was humanity’s first run-in with coffee. So, how did coffee go from humble plant to one of the world's most consumed beverages? Jonathan Morris traces the history of this energizing elixir. Lesson by Jonathan Morris, directed by Harry Tennant.

Anger is a complicated emotion. It can feel reasonable and righteous or impulsive and uncontrollable. Anger can be an important part of letting us know when something immoral is happening, but finding the right response to those psychological alarm bells can be tricky. So, is it ever right to be angry? And if so, when? Delaney Thull takes a philosophical look at this powerful emotion. Lesson by Delaney Thull, directed by Cara Watson.

In the mid-18th century, England was crazy for ketchup. The sauce was a staple, but this ketchup wasn’t the ubiquitous red goop you’re familiar with today. In fact, it was a sweet and savory brown sauce that didn’t even have tomatoes in it. So where did this early ketchup come from, and how did it become the dip we know and love? Dan Kwartler traces the condiment's history. Lesson by Dan Kwartler, directed by Denys Spolitak.

For centuries, scholars puzzled over the hieroglyphs they found carved onto ancient Egyptian ruins, tablets, and papyri. But in 1799, a unique discovery would finally help unlock their meaning. It was a stone inscribed with three different texts: Egyptian Hieroglyphs, Demotic Egyptian, and Ancient Greek. Franziska Naether shares how scholars decoded the ancient message of the Rosetta Stone. Lesson by Franziska Naether, directed by Tim Rauch.

As of 2021, more than 36 million people were estimated to be experiencing substance use disorder. This condition spans a spectrum of patterned drug use that causes issues in a person’s life, with substance addiction at the more severe end. Why are some people more susceptible to addiction, and why can it be so difficult to treat? Judy Grisel takes a look at how addictive drugs affect the body. Lesson by Judy Grisel, directed by Gabriella Marsh.

The breathtaking geological formations of Cappadocia are one of the most astonishing landscapes on Earth. Also known as “fairy chimneys,” this impressive terrain hides an equally remarkable feat of pre-modern engineering: a network of extensive underground cities stretching deep below the surface. Who inhabited these cities, and why? Veronica Kalas uncovers the secrets of this buried history. Lesson by Veronica Kalas, directed by Serin İnan, Tolga Yıldız, Kozmonot Animation Studio.

Mestra, princess of Thessaly, was far from home. She had watched her father, King Erysichthon, plunge into a ruin of his own making. Now, to save himself, he’d sold his own daughter to the highest bidder. But Mestra refused to accept this fate and began to plan her escape. Iseult Gillespie shares the Greek myth of Mestra's bid for freedom. Lesson by Iseult Gillespie, directed by Vitalii Nebelskyi, and action creative agency.

While we’re already feeling the devastating effects of human-caused climate change, governments continue to fall short on making and executing emissions pledges that would help thwart further warming. So, what will our world look like in the next 30 to 80 years, if we continue on the current path? Shannon Odell offers a glimpse at Earth's possible future. Lesson by Shannon Odell, directed by Sofia Pashaei.

Grooming paraphernalia has been found in numerous archeological sites, many of which have included earwax removal tools. And earwax evacuation remains a popular hygienic habit today. But what is earwax? And are the efforts to eliminate it actually good for us? Henry C. Ou explores the important role earwax plays in our health. Lesson by Henry C. Ou, directed by Yuriy Polyashko, Max Zaglotskyi, Darvideo Animation Studio.

An undulating sky melds into the landscape, two silhouettes move along a balustraded walkway, and a ghostly figure’s features extend in agony. Since Norwegian artist Edvard Munch created "The Scream" in 1893, it’s become one of the world’s most famous artworks. But why has its cry traveled so far and endured so long? Noah Charney shares the inspiration behind the dramatic and haunting masterpiece. Lesson by Noah Charney, directed by Martina Meštrović.

Asano Naganori, lord of Akō domain, fixed his gaze on Kira Yoshinaka, a senior master of ceremony. Asano extended his short sword, charged through the castle, and struck Kira. While the wound wasn’t fatal, its consequences would be. What brought about this violent quarrel? And what would come of Asano and his samurai? Adam Clulow shares the legend of the 47 Rōnin and their quest for revenge. Lesson by Adam Clulow, directed by Arvind Singh Jeena, Anantha Krishnan, Totem Creative.

Corruption is often defined as misuse of a position of power for personal gain. And while corruption in politics is nothing new, it isn’t limited to the political sphere; it can happen in schools, sports, businesses, or religious institutions. So, what exactly is corruption, and what can we do to combat it? Stephanie Honchell Smith explores the importance of transparency in building public trust. Lesson by Stephanie Honchell Smith, directed by Jeff Le Bars, JetPropulsion.space.

In May of 1945 the Third Reich was in chaos. Adolf Hitler was dead and German surrender was imminent. But while World War II was almost over, a new war was brewing. And the US was eager to recruit the smartest minds in Germany before the Soviets got the chance— regardless of their affiliation with the Nazis. This became known as Operation Paperclip. Brian Crim digs into the clandestine campaign. Lesson by Brian Crim, directed by Jeff Le Bars, JetPropulsion.space.

A group of strangers have gathered to design a just society. To ensure none of them rig the system, they’ve been placed under a veil of ignorance. Under this veil, they’re blind to information about age, sex, profession, wealth, religion, and so on. Can they build a fair society where everyone has the resources they need? Joseph Lacey details John Rawls' classic thought experiment. Lesson by Joseph Lacey, directed by Eoin Duffy.

A mathematician with a knife and ball begins slicing and distributing the ball into an infinite number of boxes. She then recombines the parts into five precise sections. Moving and rotating these sections around, she recombines them to form two identical, flawless, and complete copies of the original ball. How is this possible? Jacqueline Doan and Alex Kazachek explore the Banach-Tarski paradox. Lesson by Jacqueline Doan and Alex Kazachek, directed by Mads Lundgård.

During the 8th century CE, warfare and failing agriculture forced Maya people to move north, to hotter, drier Yucatán. Because of its freshwater access, Chichen Itza became the most powerful Maya city, with nearly 50,000 citizens at its height. But the region presented its own challenges and the city's golden age wouldn’t last forever. Geoffrey E. Braswell traces the city's rise and fall. Lesson by Geoffrey E. Braswell, directed by Hernando Bahamon, Globizco Studios.

You might think of gas masks as clunky military-looking devices. But in the near future, we may need to rely on these filters as part of our everyday lives. In addition to emerging diseases, wildfire frequency has more than tripled, and climate change has increased toxic ground level ozone. So how do these masks work, and can they protect us from airborne threats? George Zaidan investigates. Lesson by George Zaidan, directed by Michael Kalopaidis, Zedem Media.

Many people would say the connection between happiness and gratefulness is very simple: when you are happy, you are grateful. But think again. Is it really the happy people that are grateful? Quite a number of people have everything that it would take to be happy, and they are not happy. So, how does gratefulness work? Explore the key components to living gratefully. Directed by Avi Ofer.

For most of the world’s 4,000 mayfly species, adulthood lasts roughly one day. And for some species, it’s only a matter of minutes. This isn’t because they’re all eaten up by predators. Rather, this abridged adulthood is a natural part of their life cycle. So, what role do these bugs play in their ecosystems? Luke M. Jacobus explores the stunningly short life span of the winged insects. Lesson by Luke M. Jacobus, directed by Denys Spolitak.

Philosopher Hannah Arendt was a German Jew who dedicated herself to understanding how the Nazi regime came to power, and more specifically, how it inspired so many atrocities. She believed the true conditions behind the unprecedented rise of totalitarianism weren’t specific to Germany, and developed theories on how to best combat such threats. Joseph Lacey explores the work of Hannah Arendt. Lesson by Joseph Lacey, directed by Sarah Saidan.

In the millions of years since oxygen began saturating Earth’s oceans and atmosphere, most organisms have evolved to rely on this gas. However, there are some places where oxygen-averse microorganisms like those from Earth’s earliest days have re-emerged. And one such place is hidden high in the Swiss Alp’s Piora Valley. Nicola Storelli and Daniele Zanzi dive into the depths of Lake Cadagno. Lesson by Nicola Storelli and Daniele Zanzi, directed by Ivana Volda, Thomas Johnson Volda.

Under certain conditions, the idea of a dictator can sound appealing, like when a democracy isn’t functioning as it should due to corruption or political polarization. People may believe the solution is a "benevolent dictator"— a leader who only uses their absolute power for the common good. But can such a leader actually exist in today’s world? Stephanie Honchell Smith examines this common myth. Lesson by Stephanie Honchell Smith, directed by Avi Ofer.

A couple has been considering getting engaged, but they’re worried about divorce statistics. An AI-based model was just released that can predict your likelihood of divorce with 95% accuracy. The only catch is the model doesn’t offer any reasons for its results. So, should they decide whether or not to get married based on this AI’s prediction? Thomas Hofweber explores AI’s transparency problem. Lesson by Thomas Hofweber, directed by Hannah Lau-Walker.

Spelling reformers have been advocating for changes to make English spelling more intuitive and less irregular. One example of its messiness: take the “g-h” sound from “enough,” the “o” sound from “women” and the “t-i” sound from “action,” and you could argue that “g-h-o-t-i” spells “fish.” So, how did English get like this? Arika Okrent explores the complexity of English spelling conventions. Lesson by Arika Okrent, directed by Emily Howells, Aaron Brady.

Typically, with any piece of technology, you pump one unit of energy in and you get about one out. That’s just the first law of thermodynamics: energy has to be conserved. But there’s a piece of technology called a heat pump, where for every bit of energy you put in, you get three to five times as much heat out. What wizardry is this? Anna Rothschild investigates the science of heat pumps. Lesson by Anna Rothschild, directed by Kevin Herrmann, AIM Creative Studios.

Ice cream has a unique role in our world’s history, culture, and cravings. The first accounts of cold desserts date back to the first century, in civilizations including ancient Rome, Mughal India, and Tang Dynasty China. Yet the cream-based delicacy we know today made a much later debut. So, how did the delicious sweet treat come to be? Vivian Jiang shares the scoop on the history of ice cream. Lesson by Vivian Jiang, directed by Masayoshi Nakamura, Good General

According to legend, in the 27th century BCE, the Yellow Emperor of China charged his historian, Cangjie, to develop a system of writing. Sitting alongside a riverbank, Cangjie noted the imagery that surrounded him. From this, he created the first Chinese characters. So, how has Chinese evolved in the last 3,000 years? Gina Marie Elia explores the history of one of the earliest written languages. Lesson by Gina Marie Elia, directed by PeiHsin Cho.

Each year, approximately 20 million people receive a cancer diagnosis. At that time, a patient usually learns their cancer’s stage, which is typically a number ranging from one to four. While staging is designed, in part, to help patients better understand what they’re facing, the number can be confusing. So, what do cancer stages actually mean? Hyunsoo Joshua No and Trudy Wu explain. Lesson by Hyunsoo Joshua No and Trudy Wu, directed by Jess Mountfield.

Stars have cores hot and dense enough to force atomic nuclei together, forming larger, heavier nuclei in a process known as fusion. In this process, the mass of the end products is slightly less than the mass of the initial atoms. But that “lost” mass doesn’t disappear — it’s converted to energy ... a lot of energy. So, can we harness this energy to power the world? George Zaidan investigates. Lesson by George Zaidan, directed by Igor Ćorić, Artrake Studio.

Globally, around 23 million pregnancies end in miscarriage each year. Despite how common it is, miscarriage can still feel isolating, and for some, emotionally traumatizing. And myths about miscarriage add to the stigma, leading many to blame themselves for the loss. So what happens in the body during miscarriage? Nassim Assefi & Emily M. Godfrey take a closer look at pregnancy loss and treatment. Lesson by Nassim Assefi and Emily M. Godfrey, directed by Lené van Heerden, We Are Batch TV. A special thanks to the World Health Organization who provided information and insights for the development of this video.

Recent studies found that elite runners can take in twice as much oxygen as non-runners. And it’s likely that this superhuman ability played a role in breaking the two-hour marathon barrier in 2019. But when it comes to breathing efficiently, not even the best runners can compete with the average fish. What makes fish some of the best breathers on Earth? Dan Kwartler explores the science of gills. Lesson by Dan Kwartler, directed by Denys Spolitak.

When Cadmus walked the Earth, just a few generations separated him from his divine ancestors. From atop Mount Olympus, they scrutinized and meddled with mortals like himself. Cadmus was a skilled warrior and heir to the Phoenician throne, but he wouldn’t stay in the gods’ favor for long— a critical mistake would seal his tragic fate. Iseult Gillespie details the Greek myth of the serpent’s curse. Lesson by Iseult Gillespie, directed by Adriana Monteforte Lahera.

An alligator snapping turtle lures its prey using a blood-engorged tongue that resembles a wriggling worm. And it’s far from the only animal doing tongue trickery. Tongues in the animal kingdom vary widely — from texture and length, to shape and dexterity. So, what's the point of having so many different kinds of tongues? Cella Wright explores how different species use the appendage to survive. Lesson by Cella Wright, directed by Igor Ćorić, Artrake Studio.

Astronauts aboard the space station Mir made a frightening discovery: several species of Earth-derived fungi were found growing throughout the shuttle, blanketing air conditioners and corroding control panels, putting both the station’s integrity and their lives at risk. How had the fungi survived the journey to space? Shannon Odell shares why fungi may be the key to our future on other planets. Lesson by Shannon Odell, directed by Denys Spolitak.

It's something we've all experienced: the back of your elbow smacks against a hard surface and the impact sends a sensation so distinctly disquieting shooting down your arm that it takes several moments to regain composure. So, why does hitting this spot on your elbow— commonly known as the funny bone— feel so weird? Cella Wright explains one of the most complicated joints in the body. Lesson by Cella Wright, directed by Anton Bogaty.

Throughout the 1980s, oil industry reps discussed the dangers of burning fossil fuels, acknowledging the risk their product posed to the future of humanity. However, instead of warning the public or pivoting towards renewable energy sources, they doubled down on oil — and launched a decades-long campaign to discredit climate change science. Stephanie Honchell Smith digs into Big Oil's tactics. Lesson by Stephanie Honchell Smith, directed by Sofia Pashaei.

Wigs date at least as far back as ancient Egypt, where well-regarded hairdressers crafted them into intricate styles. And under certain ancient Roman dynasties, women’s wigs became particularly ornate. Yet it wasn’t until Louis XIII unveiled a magnificent mane in the 17th century that big wigs truly began booming. Stephanie Honchell Smith details the rise and fall of the bewigged fashion craze. Lesson by Stephanie Honchell Smith, directed by Patrick Smith.

Within the periodic table loom many potential hazardous elements. Some elements are dangerous due to their toxicity. Others are dangerous because of how they respond, react, or even explode in the outside environment. And perhaps the most threatening elements are those that silently emit energy. So, which substances on the periodic table are the most dangerous? Shannon Odell investigates. Lesson by Shannon Odell, directed by Anton Bogaty.

Throughout history, people have attributed warts to contact with things like sea foam, boiled egg water, and, of course, toads. Fortunately, we now know that warts are not caused by toads, but are actually caused by human papillomaviruses, or HPVs. So, how exactly do HPVs lead to warts? And what should you do if you get one? Cella Wright explores the science of these bumpy skin growths. Lesson by Cella Wright, directed by Anton Bogaty.

In the 5th century, a ship master was suffering from a nasty infection that caused his jaws to press together, his teeth to lock up, and the muscles in his neck and spine to spasm. Today we know this account to be one of the first recorded cases of tetanus. So, what causes this peculiar infection? Louise Thwaites explores how tetanus affects our bodies, and how we can prevent it. Lesson by Louise Thwaites, directed by Andrew Foerster, Rewfoe.

By 1975, Richard Davis had been shot at close range 192 times. But not only was he completely healthy, each of those bullets were part of a demonstration to sell his new product: the bulletproof vest. So, how does such a light, flexible piece of clothing stop a bullet? The secret was a synthetic fiber material invented a decade earlier. Max G. Levy explores the incredible strength of kevlar. Lesson by Max G. Levy, directed by Vitalii Nebelskyi, and action creative agency.

Whales frequently surface to take in air and let out massive plumes of waste. And while this slurry might seem disgusting, whale poop is much more desirable than it may seem. In fact, it may be one of the most important substances in the ocean — and the world. So, what makes whale poop so vital to our ecosystems? David Biello shares the surprising benefits of whale excrement. Lesson by David Biello, directed by Joseph Clark, Oh Studio.

Laocoön, a seer and priest, was deeply suspicious of the enormous wooden horse that the Greeks left in Troy and cautioned the Trojans not to accept this strange offering. But their fate was already sealed — the gods granted the Greeks victory and punished the priest for threatening their success. Noah Charney explores how Laocoön’s tragic tale inspired countless artists across the ancient world. Lesson by Noah Charney, directed by Michael Kalopaidis, Zedem Media.

Shock seized the West African Dagara village as word travelled of a new decree. Completely disregarding time-honored naming rituals, the tyrannical chief declared that he alone would name the village’s children. But soon an unlikely challenger appeared: Yagangnaa, the boy who named himself. Paschal Kyiiripuo Kyoore shares the tale of the defiant boy and his battle of wits with the chief. Lesson by Paschal Kyiiripuo Kyoore, directed by Lesego Vorster, The Hidden Hand Studios.

Imagine a scientist who has teleported to space. His spacesuit’s pressurized air protects his bodily fluids from vaporization, its oxygen tank keeps him breathing, and the insulation prevents him from freezing. But although these features thwart an immediate tragedy, space is still an incredibly dangerous place. So, what does a prolonged stay in space do to the human body? Tejal Gala investigates. Lesson by Tejal Gala, directed by Henrique Barone.

Zebras belong to the same equine family as horses and donkeys. After their lineage entered Africa, they evolved into three zebra species, lived in social herds, grazed on grasses, and evaded fierce predators. One mystery that has perplexed prominent scientists for decades is the matter of their coats: why are they striped? Cella Wright digs into the common theories about the unique patterning. Lesson by Cella Wright, directed by Sharon Colman.

In 1961, an Antarctic expedition took a harrowing turn: Dr. Leonid Rogozov began feeling feverish, with an excruciating pain in his right side. It soon became clear that he had appendicitis. While Rogozov’s predicament was extreme, appendicitis is not uncommon; affecting roughly one in 12 people. So, what causes appendicitis? And why is this organ so prone to bursting? David R. Flum investigates. Lesson by David R. Flum, directed by Igor Ćorić, Artrake Studio.

For some animals, losing a limb is a decidedly permanent affair. But for salamanders, particularly axolotls, amputation is just a temporary affliction. Not only can they grow back entire limbs in as little as six weeks, they can also regenerate heart and even brain tissue. So, how does this astonishing adaptation work? Jessica Whited explores the incredible regenerative capacity of salamanders. Lesson by Jessica Whited, directed by Anton Bogaty.

Between 2011 and 2022, the deadliest kitchen appliances in the US were ovens and ranges; taking lives by causing fires and leaking carbon monoxide. These kinds of sudden, catastrophic fatalities are thankfully rare. But the kitchen dangers that cause the most casualties may actually be less immediate, and more gradual. George Zaidan explores the safety of common kitchen appliances. Lesson by George Zaidan, directed by Anastasiia Falileieva, Studio Plastic Bag.

From incantations in ancient Egypt, bloodletting in 18th century Europe, to President Coolidge inhaling poisonous chlorine gas in 1924, the common cold has inspired a variety of creative treatments. Today pharmacies are filled with an endless assortment of cold remedies. But how do these products work? And are they effective? Explore the most common categories of cold medicines and their purposes.

Thirteen billion years ago, the gas and dust particles that eventually became our Milky Way were whizzing around in every direction. Despite the wild motion of its parts, the galaxy as a whole was rotating about an axis. So why did the Milky Way, like most galaxies, become flat, and not spherical like stars and planets? Scott Hershberger explores the ever-evolving structure of our galaxy. Lesson by Scott Hershberger, directed by Josh O'Caoimh, Mikai Geronimo.

Do you ever feel tired? Overwhelmed? Depressed? Do you have headaches, dizziness, cramps, difficulty breathing? From 300 BCE to the 1900s, if you answered yes to any of these questions and you had a uterus, a doctor would likely diagnose you with hysteria. So, where did this medical diagnosis come from? And why did it persist for so long? Mark S. Micale traces the history of the catch-all term. Lesson by Mark S. Micale, directed by Laura Jayne Hodkin.

In 1873, fishermen glimpsed what they thought was a shipwreck. But when they probed the mass, it moved— and huge, serpentine appendages soon besieged their boat. One fisherman took an axe to the animal, and it disappeared in a cloud of ink, leaving behind definitive evidence that giant squids were more than mythical monsters. So, what do we know about these creatures? Anna Rothschild investigates. Lesson by Anna Rothschild, directed by Vitalii Nebelskyi, and action creative agency.

Your granddaughter created a surprise for your birthday: a holographic map displaying everywhere you’ve traveled— not just on Earth, but through the universe. Considering you’re living on a spinning rock hurtling around a sun whizzing through a galaxy, you’ve made some real progress. But, how much, exactly? Fabio Pacucci and Lindsay DeMarchi explore how far you travel over the course of your life. Lesson by Fabio Pacucci and Lindsay DeMarchi, directed by Vicente Numpaque, Hernando Bahamon, Globizco Studios.

Insects are the world’s most numerous and diverse animals. Even where you’d least expect them in some of Earth’s most extreme environments, there they are. From a scalding volcano, parched desert, to a frigid glacier, insects are living life on the edge. So, how do they do it? Charles Wallace illuminates the incredible survival skills of insects living in some of Earth's harshest ecosystems. Lesson by Charles Wallace, directed by Raghav Arumugam, Jagriti Khirwar.

Born to a sea nymph and a king, and trained by the legendary centaur Chiron, Achilles was a demigod destined for greatness. When Greece declared war on Troy, Achilles knew the war was written into his destiny. With horses born from the west wind and a spear wrought from a mountain peak, he readied himself for battle. Iseult Gillespie tells the tale of the infamous warrior and his heel. Lesson by Iseult Gillespie, directed by Luis Torres, Mr. Flama.

Humans have known about the toxicity of death cap mushrooms for millennia. Yet they continue to pose a significant threat to unsuspecting foragers and mushroom hunters throughout the world. Today, death caps are responsible for more than 90% of all mushroom related deaths, killing upwards of 100 people each year. So, what makes this one species of mushroom so dangerous? Michael Beug investigates. Lesson by Michael Beug, directed by Denys Spolitak.

While his disciples loved their roguish leader, Sun Wukong’s misadventures had spread chaos throughout the land. The Jade Emperor, watching from his throne in Heaven, decided he would no longer stand by as this monkey wreaked havoc across his domain. The Emperor decided the best way to maintain order was to keep a close eye on Sun Wukong. Ji Hao follows the Monkey King's exploits in Heaven. Lesson by Ji Hao, directed by Mohammad Babakoohi, Yijia Cao.

In the 1600s, Isaac Newton conducted a series of experiments to better understand the lights and colors that sometimes appear when your eyes are closed. If you’ve ever sat around an evening campfire or unintentionally glanced at the Sun, you may have noticed illuminated patterns briefly dance along your vision. So how do these visual illusions form? Paul Taylor explores the science of afterimages. Lesson by Paul Taylor, directed by Sofia Pashaei.

Yet another party of adventurers has broken into your lair to slay your minions and steal your treasures. Judging by the trail of destruction, you’re up against a fighter, a rogue, and a cleric. The first two won’t be a problem for a powerful necromancer like you— but the clerics' spells are trouble. Can you figure out which adventurer is the cleric before it’s too late? Alex Rosenthal shows how. Lesson by Alex Rosenthal, directed by Igor Ćorić, Artrake Studio.

A century after its discovery, insulin remain essential in treating diabetes, and has a relatively low production cost, with a vial generally costing less than $6 to make. But those in the US pay on average 10 times more than those in other countries— leading some patients to take less than prescribed. Kiah Williams takes a look at the US supply chain to explore why medications are so expensive. Lesson by Kiah Williams, directed by Tolga Yıldız, Serin İnan, Kozmonot Animation Studio.

In many parts of the world heat waves are happening more often with greater intensity and for longer durations. By 2050, Earth’s mid-latitudes could be experiencing extreme heat between 90 and 180 days a year, with tropical regions enduring even more. So how hot is too hot, and what can people do to handle the heat? Carolyn Beans digs into how heat waves affect your body. Lesson by Carolyn Beans, directed by Reza Riahi.