Season 5

    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?

    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 Where Did Life Come From? (feat. PBS Space Time and Eons!)

    It's Okay to Be Smart

    Where Did Life Come From? (feat. PBS Space Time and Eons!)

    Let’s journey back to the origin of life, as best as we know it.

    Where Did Life Come From? (feat. PBS Space Time and Eons!)

    Video thumbnail: It's Okay to Be Smart Can You Bend Light Like This?

    It's Okay to Be Smart

    Can You Bend Light Like This?

    Light bending experiments tested!

    Can You Bend Light Like This?

    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

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