Season 5

Video thumbnail: It's Okay to Be Smart Why Do We Itch?

It's Okay to Be Smart

Why Do We Itch?

Why does it feel better when you scratch an itch and what is itching for?

Why Do We Itch?

Video thumbnail: It's Okay to Be Smart 97% of Climate Scientists Really Do Agree

It's Okay to Be Smart

97% of Climate Scientists Really Do Agree

97% of climate scientists really agree that humans are the main cause of climate change.

97% of Climate Scientists Really Do Agree

Video thumbnail: It's Okay to Be Smart Could You Be Immune To Everything?

It's Okay to Be Smart

Could You Be Immune To Everything?

With scientists learning more about immune systems, could we ever be immune to everything?

Could You Be Immune To Everything?

Video thumbnail: It's Okay to Be Smart Why Are There As Many Males As Females?

It's Okay to Be Smart

Why Are There As Many Males As Females?

In most cases, an equal balance of the sexes is the evolutionary stable strategy.

Why Are There As Many Males As Females?

Video thumbnail: It's Okay to Be Smart Defusing the Population Bomb

It's Okay to Be Smart

Defusing the Population Bomb

Is overpopulation real? Human overpopulation is a major concern for many people

Defusing the Population Bomb

Video thumbnail: It's Okay to Be Smart Tuatara All the Way Down

It's Okay to Be Smart

Tuatara All the Way Down

Meet the chillest reptile, weird living fossil...the tuatara.

Tuatara All the Way Down

Video thumbnail: It's Okay to Be Smart The Most Extreme Life Forms On Earth… And Beyond?

It's Okay to Be Smart

The Most Extreme Life Forms On Earth… And Beyond?

Extremophiles find a way to survive and expand the possibilities of where life can exist.

The Most Extreme Life Forms On Earth… And Beyond?

Video thumbnail: It's Okay to Be Smart Why Is Blue So Rare In Nature?

It's Okay to Be Smart

Why Is Blue So Rare In Nature?

Learn how living things make blue, and why this beautiful hue is so rare in nature.

Why Is Blue So Rare In Nature?

Video thumbnail: It's Okay to Be Smart How Atom Bombs Can Uncover Forged Art

It's Okay to Be Smart

How Atom Bombs Can Uncover Forged Art

Here’s some of the amazing ways that science can detect fake art.

How Atom Bombs Can Uncover Forged Art

Video thumbnail: It's Okay to Be Smart Why Do You Love Your Family?

It's Okay to Be Smart

Why Do You Love Your Family?

Why do we feel such a deep sense of connection with our family members?

Why Do You Love Your Family?

Video thumbnail: It's Okay to Be Smart 20 MILLION Year-Old Spider!! Unweaving Spider Silk 🕷

It's Okay to Be Smart

20 MILLION Year-Old Spider!! Unweaving Spider Silk 🕷

Spider silk is as strong, stretchy, and resilient as even humans’ most advanced creations.

20 MILLION Year-Old Spider!! Unweaving Spider Silk 🕷

Video thumbnail: It's Okay to Be Smart The Romantic Lure of Moonlight

It's Okay to Be Smart

The Romantic Lure of Moonlight

Many animals use moonlight and Earth’s lunar cycle to run their biological clock.

The Romantic Lure of Moonlight

Video thumbnail: It's Okay to Be Smart Should You Eat Everyday?

It's Okay to Be Smart

Should You Eat Everyday?

A look at the science behind intermittent fasting.

Should You Eat Everyday?

Video thumbnail: It's Okay to Be Smart The Cheerios Effect

It's Okay to Be Smart

The Cheerios Effect

Who knew there was so much science in a bowl of cereal?

The Cheerios Effect

Video thumbnail: It's Okay to Be Smart Doomsday Machines

It's Okay to Be Smart

Doomsday Machines

Nuclear weapons represent the darker side of E=mc^2.

Doomsday Machines

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