Humans (and our pets) frequently instinctively stretch as soon as we wake up. But why? What is happening in our bodies when we stretch and yawn to wake ourselves up?

For as long as we've had language, some people have tried to control it. And some of the most frequent targets of this communication regulation are the ums, ers, and likes that pepper our conversations. These linguistic fillers occur...

"A record of our emotional life is written on our hearts," says cardiologist and author Sandeep Jauhar. In a stunning talk, he explores the mysterious ways our emotions impact the health of our hearts -- causing them to change shape in...

At some point, you may have noticed a poster or photo with eyes on it hanging somewhere public. What you probably didn't notice is the effect that picture has on your brain.

The average 20-year-old knows between 27,000 and 52,000 different words. Spoken out loud, most of these words last less than a second. With every word, the brain has a quick decision to make: which of those thousands of options matches...

Hank tells us about NASA's Near-Earth Object Program, which tracks the paths of asteroids and categorizes them according to the likelihood that they will strike the Earth at some point in the future.

Sitting down for brief periods can help us recover from stress or recuperate from exercise. But nowadays, our lifestyles make us sit much more than we move around. Are our bodies built for such a sedentary existence? Murat Dalkilin�c...

CubeSats have a lot of advantages, but they need a way to move and still stay small, and that means new miniaturized propulsion systems that can help us get these tiny spacecraft out into the universe.

You know how resolutions often go: you set a goal and start strong ... then the motivation runs out and feelings of frustration and shame creep in. The struggle is real -- but what if it doesn't have to be? Sociologist Christine Carter...

After drinking a few glasses of water on a hot day, you might be struck with a sudden urge. Behind that feeling are two bean-shaped organs that work as fine-tuned internal sensors. Emma Bryce details how the incredible kidneys balance...

Explore inheritance when carried on the X chromosome with the Amoeba Sisters! This video focuses on how to do general Punnett square problems that involve traits on the sex chromosomes (X and Y chromosomes). We do want to point out...

You know what's amazing? That we can talk to people, they can make meaning out of it, and then talk back to us. In this episode of Crash Course Psychology, Hank talks to us and tries to make meaning out of how our brains do this thing...

Hank explains speciation - the evolutionary process by which new biological species arise - in terms of finches, ligers, mules, and dogs.

You might’ve heard people talking about how awesome psychotherapy can be, but is it actually effective?

Language is complex, and when abstract or nuanced concepts get lost in translation, the consequences may be catastrophic. Given the complexities of language and cultural exchange, how do these epic miscommunications not happen all the...

What would it be like to have a limitless memory? Can the meaning of life be found in an infinite library? Is time a labyrinth or a single moment? Jorge Luis Borges explored these questions of infinity in his many works. His body of...

1, 11, 21, 1211, 111221. These are the first five elements of a number sequence. Can you figure out what comes next? Alex Gendler reveals the answer and explains how beyond just being a neat puzzle, this type of sequence has practical...

Teflon was in the spacesuits the Apollo crew wore for the moon landing, in pipes and valves used in the Manhattan project, and it may be in your kitchen, as the nonstick coating on frying pans and cookie sheets. So what is this slippery...

Vitamins are the building blocks that keep our bodies running; they help build muscle and bone, capture energy, heal wounds and more. But if our body doesn't create vitamins, how do they get into our system? Ginnie Trinh Nguyen describes...

To figure out an organism's genome and DNA sequence, field biologists need big, expensive equipment in the labs. But, new high-tech devices help scientists to examine samples on the sites!

Fruit trees are unpredictable and grow slowly, and consumer tastes are fickle, so successful new varieties of fruit are rare

Have you ever felt like you're talking, but nobody is listening? Here's Julian Treasure to help. In this useful talk, the sound expert demonstrates the how-to's of powerful speaking -- from some handy vocal exercises to tips on how to...

Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo' is a grammatically correct sentence. How? Emma Bryce explains how this and other one-word sentences illustrate some lexical ambiguities that can turn ordinary words and...

Last week we talked about language and meaning. Today, Hank explores some of the things that complicate meaning and how we get around that. We’ll explain conversational implicature, the cooperative principle, and the four main maxims of...