Can trees really save us from climate change? For eons, nature has relied on photosynthesis as a big way to keep carbon dioxide levels from getting out of control. But as we have put more carbon into the air, we’ve also cut down many of the forests we need to suck that carbon up. So big tree-planting initiatives like #TeamTrees to the rescue, right? Actually, we need to think bigger. Here’s three ways trees really can help us solve climate change, from a guy who wants to plant a TRILLION trees, to how we might save the forests we’ve got, to scientists hacking biology to make trees even better.

If you tried to sum up the last 150 years or so in one image, a chart of exponential growth would be a good place to start. It shows that some things change faster over time. You could apply it to life expectancy. Or compound interest. Or any number of things. But especially population growth. Back in 1798 a guy named Thomas Malthus noticed that not everything grows this way. And this caused people to worry, because they were sure it would lead to massive death and starvation and famine. But that didn’t happen, thanks to something called the Green Revolution and a guy named Norman Borlaug. As we face a future population of ten billion and a world impacted by climate change, how will we do a Green Revolution 2.0?

The first thing a baby giraffe experiences after being born is a 2 meter fall straight down to the ground. But within an hour, it’s standing, walking, and nursing on its own. And a blue whale calf, after nearly a year growing inside mom, can swim to the surface moments after being born. Human babies on the other hand? We’re born unable to move or eat on our own, we can’t communicate or fully sense our world, and we leak EVERYWHERE. If humans are so smart, why are our babies so… un-smart? You may think it’s all about head size, but the real science is more complex.

If the sun instantly switched off like a light bulb–which can’t happen, by the way–then we wouldn’t know for almost 8 and a half minutes. Light travels at the fastest speed there is, but it still takes almost 500 seconds to get to Earth. That’s how long it would take before we knew the sun went dark.But the most amazing thing about the sunlight we see is it’s actually really old. SUPER old. AMAZINGLY OLD! Tens of thousands of years old. How is that possible? Because of the physics and mathematics of random walks.

Every year, hundreds of millions of people voluntarily turn their lives upside down by setting their clocks forward one hour in the spring and back one hour in the autumn on a particular date mandated by the government wherever they happen to live. Daylight saving time is a perfect example of how a few people with the best of intentions can end up annoying millions of the rest of us for the better part of a century. And it’s time we take an honest look at how we got to this place where half the world comes unstuck in time twice a year, and ask if the supposed advantages for springing forward and falling back still hold up!

Stay informed. Stay cautious, but not scared. Listen to scientists and public health officials and follow their guidance. By protecting yourself, you’re protecting the most vulnerable among us. Together we can flatten the curve on COVID-19 and SARS-CoV-2. More resources below!

One of the most effective things you can do to protect yourself from catching a germ and becoming a statistic, whether it’s a global pandemic like COVID-19 or just every single other day of your life, is something that people have been trying to get you to do since you were like 2. Wash your hands. With good ol’ soap. And do it the right way. That’s it. Here’s the science of handwashing!

I’ve explained a lot of weird bodily functions on this show but there’s one that we haven’t covered that’s always confused me: Tickling. What are you for, tickling? What’s the point of you? Why do you exist? Why do you make us laugh even though we hate you? Let’s dig into our evolutionary past to try and find an answer.

SARS-CoV-2 and COVID-19 are nasty enemies. Invisible, mysterious, and deadly, they have spread around the world and caused much of humanity to hide away. Germs like these only succeed and spread because of our social evolution, and our social nature is why social and physical distancing is so deeply painful for us. But evolution has also given us the gifts we need to survive this difficult time. Here’s how.

Viruses keep jumping out of nature and into humans, and getting us very sick in the process. So why do zoonotic spillovers like SARS-CoV-2 happen, and why are they becoming more frequent? We asked an expert.

The largest pterosaurs like Quetzalcoatlus were closer in size to airplanes than birds. No flying animal alive today comes close to their huge size. So did giant pterosaurs actually fly? I went to see the fossil bones of the largest pterosaur that ever lived so I could learn how these winged giants actually took to the skies.

There’s a lot of confusion out there about what is and isn’t a dinosaur. And you’d be forgiven for being kinda confused. Maybe paleontologists are just messing with us. Or… maybe the question of what is and isn’t a dinosaur goes deeper than we think? Well, like an intrepid fossil hunter, I set out to dig up an answer, and what I found teaches us a lesson about how hard it is to build a picture of the past when you only have a few puzzle pieces, and a lot about why we classify things the way we do.

Wearing a mask is a cheap and easy way to help stop the spread of airborne infections like COVID-19. It’s also a sign that you want to help protect other people and have them protect you… that we’re all in this together. Here’s some awesome slow-motion schlieren imaging experiments to demonstrate why masks work! Share with someone who needs to see this.

Bottom line: Masks work. They are safe for almost everyone to wear, and the more people that wear them along with adhering to physical distancing and other strategies, then that’s more lives we’ll save. But there’s still a lot of confusion and misinformation out there when it comes both to wearing masks and the actual risks of getting infected with COVID-19. In this video I address a few of the most common myths and misunderstandings using scientific evidence.

Having bones is pretty cool. They make our blood, let us hear, and keep us from being just a squishy puddle on the floor. But for every species with bones, there’s at least 20 species on Earth with exoskeletons instead. And those exoskeleton animals are incredibly tough and strong. So why don’t WE have our skeletons on the outside? This is the story of bones!

Time passes for all of at the saem rate of one second per second. But why does it sometimes feel like time is passing so fast, or so slowly? Especially during COVID? Let’s learn about how our brains keep track of and try to make sense of time, and how they get fooled.

The fastest animal in nature isn’t what you think it is. It’s way, way smaller than that. Nature’s tiniest creatures warp the laws of physics, and they do it in ways that even human engineers would gawk at. Using the power of super slow-motion macro video, let’s uncover the biological engineering that lets nature’s fastest creatures do their zoomy thing.

I don’t want to alarm you, but the world is going to end. All of this. Gone. And scientists are certain all of this will happen. On the bright side this isn’t going to happen for 4-5 billion years. It makes me wonder: In a universe bigger than we can fathom, across eons of time, could… all of it end? Everything? The whole universe? Yes. And it probably will. Here’s how.

Geckos can grip and climb almost anything. Walking up walls, hanging upside down… even from glass. It’s almost like they can defy gravity. How do they do it? The secret lies in nanotechnology. I’ll tell you how that works and how scientists are using this incredible gripping ability to inspire next-generation adhesives

Why does everyone use a 7 day week, and where did it come from? Where do the names of the days come from? And who can we blame for Mondays? Here’s the true story of one of the oldest human customs still in use today. It gets a little weird.

You’ve probably heard of Ben Franklin and the kite. But do you know the TRUE story of how his famous experiment changed the world? Here’s the tale of how one person’s quest for scientific knowledge altered the direction of history.

Here we are, just a year after the first news of the coronavirus we now call SARS-CoV-2 and the global pandemic known as COVID-19… and scientists have already developed more than one safe & effective vaccine. How did they do that so quickly? I visited the lab whose work directly led to these first COVID vaccines, so you can learn how basic research connects to life-saving medicine. This is how to make a COVID-19 vaccine.