TED-Ed
TED-ED: When will the next mass extinction occur? - Borths, D'Emic, and Pritchard
About 66 million years ago, a terrible extinction event wiped out the dinosaurs. But it wasn't the only event of this kind -- extinctions of various severity have occurred throughout the Earth's history -- and are still happening all...
TED-Ed
TED-ED: How brain parasites change their host's behavior - Jaap de Roode
The biggest challenge in a parasite's life is to move from one host to another. Intriguingly, many parasites have evolved the ability to manipulate the behavior of their hosts to improve their own survival -- sometimes even by direct...
TED-Ed
TED-Ed: How smart are dolphins? - Lori Marino
Dolphins are one of the smartest animal species on Earth. In fact, their encephalization quotient (their brain size compared to the average for their body size) is second only to humans. But exactly how smart are they? Lori Marino...
TED-Ed
TED-Ed: How do the lungs work? - Emma Bryce
When you breathe, you transport oxygen to the body's cells to keep them working, while also clearing your system of the carbon dioxide that this work generates. How do we accomplish this crucial and complex task without even thinking...
TED-Ed
TED-Ed: The cancer gene we all have - Michael Windelspecht
Within every cell in our body, two copies of a tumor suppressor gene called BRCA1 are tasked with regulating the speed at which cells divide. Michael Windelspecht explains how these genes can sometimes mutate, making those cells less...
TED-Ed
TED-ED: How do fish make electricity? - Eleanor Nelsen
Nearly 350 species of fish have specialized anatomical structures that generate and detect electrical signals. Underwater, where light is scarce, electrical signals offer ways to communicate, navigate, find, and sometimes stun prey. But...
TED-Ed
TED-Ed: The twisting tale of DNA - Judith Hauck
What do a man, a mushroom, and an elephant have in common? A very long and simple double helix molecule makes us more similar and much more different than any other living thing. But, how does a simple molecule determine the form and...
TED-Ed
TED-Ed: Myths and misconceptions about evolution - Alex Gendler
How does evolution really work? Actually, not how some of our common evolutionary metaphors would have us believe. For instance, it's species, not individual organisms, that adapt to produce evolution, and genes don't "want" to be passed...
TED-Ed
TED-ED: How do drugs affect the brain? - Sara Garofalo
Most people will take a pill, receive an injection, or otherwise take some kind of medicine during their lives. But most of us don't know anything about how these substances actually work. How can various compounds impact the way we...
TED-Ed
TED-Ed: Why do we itch? - Emma Bryce
The average person experiences dozens of individual itches each day. We've all experienced the annoyance of an inconvenient itch - but have you ever pondered why we itch in the first place? Is there actually an evolutionary purpose to...
TED-Ed
TED-Ed: What happens when your DNA is damaged? - Monica Menesini
The DNA in just one of your cells gets damaged tens of thousands of times per day. Because DNA provides the blueprint for the proteins your cells need to function, this damage can cause serious issues-including cancer. Fortunately, your...
TED-Ed
TED-Ed: Can animals be deceptive? - Eldridge Adams
A male firefly emits a series of enticing flashes. He hopes a female will respond and mate with him. A female from a different species mimics his patterns: by tricking the male, she lures him in -- and turns him into a meal. Where else...
TED-Ed
TED-Ed: How does anesthesia work? - Steven Zheng
When under anesthesia, you can't move, form memories, or -- hopefully -- feel pain. And while it might just seem like you are asleep for that time, you actually aren't. What's going on? Steven Zheng explains what we know about the...
TED-Ed
TED-Ed: Why are human bodies asymmetrical? - Leo Q. Wan
Symmetry is everywhere in nature. And we usually associate it with beauty: a perfectly shaped leaf or a butterfly with intricate patterns mirrored on each wing. But it turns out that asymmetry is pretty important, too - and more common...
TED-Ed
TED-ED: How do scars form? - Sarthak Sinha
It's hard to escape childhood without racking up a few scars. Why do these leftover reminders of a painful cut or crash look different from the rest of our skin? And why do they stick around for so long after the incident that caused...
TED-Ed
TED-ED: Why is being scared so fun? - Margee Kerr
At this very moment, people are lining up somewhere to scare themselves, be it with a thrill-ride or a horror movie. In fact, in October of 2015 alone, about 28 million people visited a haunted house in the US. But you might wonder: What...
TED-Ed
TED-Ed: How do germs spread (and why do they make us sick)? - Yannay Khaikin and Nicole Mideo
Germs are found on almost every surface we come in contact with, which makes it incredibly common for our bodies to be exposed to them. But why are some of these germs relatively harmless, while others can be fatal? Yannay Khaikan and...
TED-Ed
TED-ED: Tracking grizzly bears from space - David Laskin
Grizzly bears stick to a mostly vegetarian diet in sync with plant growing seasons. However, as grizzlies' habitats grow smaller, food is harder to come by. Using NASA satellites, scientists track the shifting, interrelated patterns of...
TED-Ed
TED-ED: The strange case of the cyclops sheep - Tien Nguyen
In the 1950s, a group of ranchers in Idaho were baffled when their sheep gave birth to lambs with only one eye. Mystified by these cyclops sheep, they called in scientists from the U.S. Department of Agriculture to investigate. What...
TED-Ed
TED-ED: Nature's smallest factory: The Calvin cycle - Cathy Symington
A hearty bowl of cereal gives you the energy to start your day, but how exactly did that energy make its way into your bowl? It all begins with photosynthesis, the process that converts the air we breathe into energizing glucose. Cathy...
TED-Ed
TED-ED: Why are there so many types of apples? - Theresa Doud
Have you ever walked into a grocery store and wondered where all the varieties of apples came from? You might find SnapDragon, Pixie Crunch, Cosmic Crisp, Jazz, or Ambrosia next to the more familiar Red Delicious and Granny Smith. So why...
TED-Ed
TED-ED: What is leukemia? - Danilo Allegra and Dania Puggioni
Stem cells found in the bone marrow are crucial for our health because they are needed to become new blood cells that sustain and protect our bodies. But when the transformation goes wrong, harmful mutations can cause the cells to start...
TED-Ed
TED-ED: Cannibalism in the animal kingdom - Bill Schutt
Until recently, scientists thought cannibalism was a rare response to starvation or other extreme stress. Well-known cannibals like the praying mantis and black widow were considered bizarre exceptions. But now, we know they more or less...
TED-Ed
TED-ED: Why are fish fish-shaped? - Lauren Sallan
In tropical seas, flying fish leap out of the water, gliding for up to 200 meters, before dipping back into the sea. In the Indo-Pacific, a hunting sailfish swims up to 110 kilometers per hour. These feats are made possible by a fish's...