Have you heard the expression “dogs are people’s best friend”? Where did it come from? And why are dogs and humans such great pals? Molly and co-host Kha-ai jump back in time to learn how dogs became humans’ best friends, and answer the question why do dogs wag their tails? Plus, we’ll also explore how dogs help humans and even other animals like cheetahs. And keep your ears perked for a brand new Mystery Sound! This episode was sponsored by: Indeed (Indeed.com/BRAINS - Terms and conditions apply. Cost per application pricing not available for everyone.) ***** Do you have your Smarty Pass yet?? Get yours today for just $4/month (or $36/year) and get bonus episodes every month, and ad-free versions of every episode of Brains On, Smash Boom Best, Moment of Um, and Forever Ago. Visit www.smartypass.org to get your Smarty Pass today!

Friendship rules! Friends help us work through problems, keep us company and bring joy to our lives. Making friends might have also helped our prehistoric ancestors survive and thrive! Still, friendship can be tough sometimes. In this episode, we’ll answer your friendship questions with Eileen Kennedy-Moore (a.k.a Dr. Friendtastic!) and hear some advice from a filmmaker with autism about making friends. Plus an all-new Mystery Sound! This episode was sponsored by: Indeed (Indeed.com/BRAINS - Terms and conditions apply. Cost per application pricing not available for everyone.) *****Do you have your Smarty Pass yet?? Get yours today for just $4/month (or $36/year) and get bonus episodes every month, and ad-free versions of every episode of Brains On, Smash Boom Best, Moment of Um, and Forever Ago. Visit www.smartypass.org to get your Smarty Pass today!

Humans need sleep to survive, but do plants doze off too? In this episode, we’ll look into how plants rest. Turns out humans and plants aren’t all that different! We’ll hear about how we share a common ancestor, way, way back in history. We’ll also learn how plants and people have little built-in clocks that tell us when it’s day and night! Oh, and Sanden parties with his plant pals and we guess an all-new Mystery Sound. This episode was sponsored by: Indeed (Indeed.com/BRAINS - Terms and conditions apply. Cost per application pricing not available for everyone.) *****Do you have your Smarty Pass yet?? Get yours today for just $4/month (or $36/year) and get bonus episodes every month, and ad-free versions of every episode of Brains On, Smash Boom Best, Moment of Um, and Forever Ago. Visit www.smartypass.org to get your Smarty Pass today!

Our big, beautiful sky stretches all the way from the ground beneath our feet to about sixty miles above the Earth. It’s made up of countless air molecules, pinging around like tiny, invisible pinballs. And even though we can’t feel the weight of each individual air molecule, all together they weigh a lot! But how much does the sky actually weigh? (spoiler alert: it involves lots and lots of farting cats…) Molly and co-host Felix learn more by talking with a band of singing walruses and a pretty wacky weatherwoman. And don’t miss this week’s extra mysterious Mystery Sound! This episode was sponsored by: Indeed (Indeed.com/BRAINS - Terms and conditions apply. Cost per application pricing not available for everyone.) Thrive Market(Thrivemarket.com/brains - Click for 30% off your first order, plus a FREE $60 gift.) *****Do you have your Smarty Pass yet?? Get yours today for just $4/month (or $36/year) and get bonus episodes every month, and ad-free versions of every episode of Brains On, Smash Boom Best, Moment of Um, and Forever Ago. Visit www.smartypass.org to get your Smarty Pass today!

Lots of creatures are able to glow, like fish, mushrooms, fireflies and even some bacteria! This special ability is called bioluminescence and it looks like magic, but it’s actually chemistry. In this episode, we’ll travel to the bottom of the ocean in the ExPLORERR to meet some super spectacular, bioluminescent friends and find out why so many animals make their own light. And we’ll hear from a scientist who uses bioluminescence in cancer research. Plus a brand new mystery sound! This episode is sponsored by: Disney Plus Originals (Disneyplusoriginals.disney.com - Disney Plus Originals' Moon Girl & Devil Dinosaur) Indeed (Indeed.com/BRAINS - Terms and conditions apply. Cost per application pricing not available for everyone.) Thrive Market (Thrivemarket.com/brains - For 30% off your first order, plus a FREE $60 gift.) ***** Do you have your Smarty Pass yet?? Get yours today for just $4/month (or $36/year) and get bonus episodes every month, and ad-free versions of every episode of Brains On, Smash Boom Best, Moment of Um, and Forever Ago. Visit www.smartypass.org to get your Smarty Pass today!