Usually when you think of evolution or natural selection, you think of survival of the fittest. But sometimes, the resulting traits of evolution aren’t the most efficient solutions to the problems at hand. With the bar set to “good...

From menstrual cycles to rainfall, there are lots of claims about the moon's influence. In today's episode, Hank is here to set the record straight with 8 myths & facts about our moon.

Unless you saw the spider bite you, that swollen, bite-looking lesion on your arm is probably something else, and blaming it on an innocent 8-legged critter might do more harm than good. Hosted by: Stefan Chin

Scientists know that the Y chromosome has been shrinking in size over millions of years, but recent studies suggest that it has more important genes, besides the ones that cause biological maleness. Hosted by: Michael Aranda

Is there a chance that more species may actually be closer to fish than we originally thought?

You might have a beard, or a mustache, or even a soul patch. What you don't have are whiskers. Hosted by: Hank Green

Unlike lots of other animals, there’s no such thing as the “mating season” for humans, and it might have to do with how we raise our kids.

You'd think that air that was the same temperature as your body would feel neutral, but if you've ever been outside when it's 37 degrees Celsius out... you know that's not the case! Hosted by: Stefan Chin

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?

A new strain of bird flu has been detected in North American birds for the first time in seven years. And U.S. President Biden is temporarily lifting the country's summertime ban on E15 gasoline.

Why is it so hard for us to keep the bears out of our trash? Well, it turns out that trash cans are basically like giant food puzzles for the bears, and they are determined to win... But, we can use their wily trash-nabbing instincts...

In today's episode Hank talks about hair: What's it good for, what's it made of, and why do we have less than other mammals?

Chimpanzees and bonobos may be very close to us humans on the tree of life, but one of our differences is the way we store fat. That difference comes down to types of fat cells and our DNA. Hosted by: Hank Green

About 10% of the world population is left-handed. But why does handedness exist and what determines which hand is dominant? Scientists have suggested several theories, but the answer may well lie with evolution.

We often think of categories as fixed, with a species being a species no matter what. The thing is, life doesn’t have to follow our rules.

Imagine opening a bag of chips, only to find Santa Claus looking back at you. Or turning a corner to see a building smiling at you. Humans see faces in all kinds of mundane objects, but these faces aren't real— they're illusions due to a...

According to the fossil record, ancient humans usually had straight teeth, complete with wisdom teeth. In fact, the dental dilemmas that fuel the demand for braces and wisdom teeth extractions today appear to be recent developments. So,...

A lot of our food comes from plants, including honey! Mister Brown and Squeaks learn how honey goes from being watery nectar in a flower to the sweet sticky substance we all know and love - and it's all thanks to bees!

Imagine that your life began as one of the planet's first humans. After dying, you're reincarnated as the second human ever to live. You then return as the third person, the fourth, the fifth, and so on – living the lives of every human...

Can AI help us see beyond our human capabilities? Through a kaleidoscopic blend of technology, nature and art, neural artist Sofia Crespo brings to life animals that push the boundaries of creativity and imagination. Her artistic...

People have been captivated by horses for a long time. They appear more than any other animal in cave paintings dating back 30,000 years. But how did horses make the journey from wild animals to ones humans could hitch themselves to and...

Mosquitoes are responsible for more human deaths every year than any other animal, but very few of the 3,500 mosquito species actually transmit deadly diseases to humans. Scientists have been conducting experiments using engineered...

Nestled in the forests of Canada sits the world's longest beaver dam. This 850-meter-long structure is large enough to be seen in satellite imagery and has dramatically transformed the region, creating a pond containing 70 million liters...

John Green is teaching history again. This time, we're looking at the history of Europe in 50 episodes. We'll start at the tail end of the so called Middle Ages, and look at how Europe's place in the world has developed and changed in...