Season 5

    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 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

    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 How to Figure Out the Day of the Week For Any Date Ever

    It's Okay to Be Smart

    How to Figure Out the Day of the Week For Any Date Ever

    Here’s a neat mental trick for calculating the day of the week for any day ever.

    How to Figure Out the Day of the Week For Any Date Ever

    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 Inside an ICE CAVE! - Nature's Most Beautiful Blue

    It's Okay to Be Smart

    Inside an ICE CAVE! - Nature's Most Beautiful Blue

    Where do glaciers and icebergs get their beautiful blue color?

    Inside an ICE CAVE! - Nature's Most Beautiful Blue

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