Season 5

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

    It's Okay to Be Smart

    The Raisin Bran Effect

    Where do you see the Brazil Nut Effect around you?

    The Raisin Bran Effect

    Video thumbnail: It's Okay to Be Smart Can We Get Older Without Aging?

    It's Okay to Be Smart

    Can We Get Older Without Aging?

    What do other life forms have to teach us about staying alive as we get old?

    Can We Get Older Without Aging?

    Video thumbnail: It's Okay to Be Smart The Dinosaur On Your Thanksgiving Table

    It's Okay to Be Smart

    The Dinosaur On Your Thanksgiving Table

    Eating turkey this holiday season? You’re eating a dinosaur!

    The Dinosaur On Your Thanksgiving Table

    Video thumbnail: It's Okay to Be Smart What is Farthest Away?

    It's Okay to Be Smart

    What is Farthest Away?

    The edge of everything might not even exist…

    What is Farthest Away?

    Video thumbnail: It's Okay to Be Smart The Deadliest Flu Season in History?

    It's Okay to Be Smart

    The Deadliest Flu Season in History?

    The 1918 Flu outbreak killed 5% of the world's population--could it happen again?

    The Deadliest Flu Season in History?

    Video thumbnail: It's Okay to Be Smart The Largest River On Earth Is In The Sky

    It's Okay to Be Smart

    The Largest River On Earth Is In The Sky

    Scientists have discovered the largest river on Earth, and it’s in the sky above.

    The Largest River On Earth Is In The Sky

    Video thumbnail: It's Okay to Be Smart Where Do Teeth Come From?

    It's Okay to Be Smart

    Where Do Teeth Come From?

    Teeth are made from some biological nanotechnology that will blow your mind.

    Where Do Teeth Come From?

    Video thumbnail: It's Okay to Be Smart What Do Raindrops Really Look Like?

    It's Okay to Be Smart

    What Do Raindrops Really Look Like?

    Raindrops are shaped like teardrops, right? Wrong! Let's discover rain's true shape.

    What Do Raindrops Really Look Like?

    Video thumbnail: It's Okay to Be Smart Is Height All in Our Genes?

    It's Okay to Be Smart

    Is Height All in Our Genes?

    Turns out the inheritance of height is a lot more complicated than we thought.

    Is Height All in Our Genes?

    Video thumbnail: It's Okay to Be Smart Will You Still Eat Raw Fish After Watching This Video?

    It's Okay to Be Smart

    Will You Still Eat Raw Fish After Watching This Video?

    Ever wondered why restaurants warn you about raw or undercooked seafood on their menus?

    Will You Still Eat Raw Fish After Watching This Video?

    Video thumbnail: It's Okay to Be Smart How Habits are Formed

    It's Okay to Be Smart

    How Habits are Formed

    Got a bad habit you can’t break? That’s because it’s literally wired into your brain.

    How Habits are Formed

    Video thumbnail: It's Okay to Be Smart How Some Words Get Forgetted

    It's Okay to Be Smart

    How Some Words Get Forgetted

    English is confusing. Its irregular verbs can teach us a lot about how languages evolve.

    How Some Words Get Forgetted

    Video thumbnail: It's Okay to Be Smart Why Do Disney Princesses All Look Like Babies?

    It's Okay to Be Smart

    Why Do Disney Princesses All Look Like Babies?

    Why do we find things cute? Let's take a scientific look.

    Why Do Disney Princesses All Look Like Babies?

    Video thumbnail: It's Okay to Be Smart 3 Incredible Examples of Evolution Hidden In Your Body

    It's Okay to Be Smart

    3 Incredible Examples of Evolution Hidden In Your Body

    Here are some stories of how evolution and natural selection made you the way you are.

    3 Incredible Examples of Evolution Hidden In Your Body

    Video thumbnail: It's Okay to Be Smart The Only Animal That Weeps

    It's Okay to Be Smart

    The Only Animal That Weeps

    Why do we cry? Here’s the science of human tears!

    The Only Animal That Weeps

    Video thumbnail: It's Okay to Be Smart The Surprising Reason We Eat Spicy Food

    It's Okay to Be Smart

    The Surprising Reason We Eat Spicy Food

    Spices and other plant ingredients have powers that make them truly magical superfoods!

    The Surprising Reason We Eat Spicy Food

    Video thumbnail: It's Okay to Be Smart It's Okay to Fart

    It's Okay to Be Smart

    It's Okay to Fart

    Farting is natural and here's how it works.

    It's Okay to Fart

    Video thumbnail: It's Okay to Be Smart Which Life Form REALLY Dominates Earth?

    It's Okay to Be Smart

    Which Life Form REALLY Dominates Earth?

    This week we break down the concept of “biomass” to judge Earth’s living things.

    Which Life Form REALLY Dominates Earth?

    Video thumbnail: It's Okay to Be Smart What’s The Hottest Hot and Coldest Cold?

    It's Okay to Be Smart

    What’s The Hottest Hot and Coldest Cold?

    Weird things happen at extreme hot and absolute cold.

    What’s The Hottest Hot and Coldest Cold?

    Video thumbnail: It's Okay to Be Smart How Evolution Turned A Possum Into A Wolf

    It's Okay to Be Smart

    How Evolution Turned A Possum Into A Wolf

    Here’s the science of convergent evolution!

    How Evolution Turned A Possum Into A Wolf

    Video thumbnail: It's Okay to Be Smart The Cosmic Origins of Earth's Water

    It's Okay to Be Smart

    The Cosmic Origins of Earth's Water

    The origin of water traces beyond the solar system to the earliest days of the universe.

    The Cosmic Origins of Earth's Water

    Video thumbnail: It's Okay to Be Smart The Deadpool Salamander That Can Regrow Limbs

    It's Okay to Be Smart

    The Deadpool Salamander That Can Regrow Limbs

    Axolotls are special salamanders. They can regenerate entire limbs!

    The Deadpool Salamander That Can Regrow Limbs

    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 What If You Never Forgot Anything?

    It's Okay to Be Smart

    What If You Never Forgot Anything?

    How does memory work? And how does… un-memory work?

    What If You Never Forgot Anything?

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