The most popular TED-Ed Lessons of 2022

Your heart beats more than 100,000 times a day. In just a minute, it pumps over five liters of blood throughout your body. But unlike skin and bones, the heart has a limited ability to repair itself. So if this organ is severely damaged, there's often only one medical solution: replacing it. Roni Shanoada explores how this complex and intricate procedure works. [Directed by Alexia Roider, Zedem Media, narrated by Addison Anderson].

In ancient Egypt, there was a spell that declared, "Be far from me, O vile cockroach." Thousands of years later, we're still trying to oust these insects. But from poison traps to brandished slippers, cockroaches seem to weather just about everything we throw at them. So, what makes cockroaches so hard to kill? Ameya Gondhalekar digs into the genetic wonders of this troublingly tenacious creature. [Directed by Irida Zhonga, narrated by Addison Anderson, music by Phil Brookes].

More than 500 years after its creation, Leonardo da Vinci's "Mona Lisa" is arguably the world's most famous painting. Many scholars consider it an outstanding work of Renaissance art— but history is full of great paintings. So, how did this particular portrait skyrocket to unprecedented fame? Noah Charney explores the factors that helped create a worldwide sensation. [Directed by Avi Ofer, narrated by Addison Anderson, music by Stephen LaRosa].

Every morning, Helios unleashed his golden chariot, and set out across the sky. As the Sun God transformed dawn into day, he thought of his son, Phaethon, below. To prove to Phaethon that he was truly his father, Helios decided to grant him anything he wanted. Unfortunately, what Phaethon wanted was to drive Helios' chariot for a day. Iseult Gillespie shares the tragic myth of the charioteer. [Directed by Raghav Arumugam and Jagriti Khirwar, narrated by Susan Zimmerman, music by Salil Bhayani, cAMP Studio].

One day, Persephone was frolicking in a meadow with the nymph, Cyane. As they admired a flower, they noticed it tremble in the ground. Suddenly, the earth split, and a terrifying figure arose. It was Hades, god of the underworld. He wrenched Persephone from Cyane, dragged her into his inky chariot, and blasted back through the earth. Iseult Gillespie shares the myth of the goddess of spring. [Directed by KERO Animation Studio, narrated by Susan Zimmerman, music by Stephen LaRosa].

In 2010, South Korea experienced a particularly cold winter. People couldn't activate their smartphones while wearing gloves, so they began wielding snack sausages— causing one company to see a 40% rise in sausage sales. So, what could sausages do that gloves couldn't? In other words, how do touchscreens actually work? Charles Wallace and Sajan Saini dig into the science of touchscreens. [Directed by Luis Torres, Mr. Flama, narrated by Addison Anderson].

Plants, animals, or minerals found in nature bear almost every color imaginable. There are two factors that influence what hues you see in the wild: physics and evolution. So, which colors are you least likely to see in the natural world? Victoria Hwang explores one of nature's rarest spectacles. [Directed by Tamara Bogovac, Artrake Studio, narrated by Alexandra Panzer, music by Nikola Radivojevic].