NOVA Presents

What Exactly Is a Law of Nature? | Robert Hazen & Michael Wong

What’s the difference between a fact, a law, and a theory? Mineralogist Robert Hazen and astrobiologist Michael Wong unpack the hierarchy of scientific ideas and reveal how laws of nature elegantly unify the universe.For more, check out the extended interview with Robert Hazen and Michael Wong.Learn more about NOVA and subscribe to our YouTube channel. 

How Many Microbes Live on Earth? | Peter Girguis

Sorry, Beyoncé, it turns out microbes rule the world. Microbiologist Peter Girguis explains how to conceptualize just how many microbes are on Earth… and how understanding this helps us look for life on other worlds. For more, check out the extended interview with Peter Girguis.Learn more about NOVA and subscribe to our YouTube channel. 

Hunt for the Oldest DNA

Scientists have discovered the oldest DNA ever found: tiny fragments hidden in the dirt. The idea that soil could hold genetic traces from creatures that vanished millions of years ago seemed impossible – until one researcher had the wild idea to go and look. But how did he find DNA that most scientists thought could never survive? What forgotten worlds can this buried DNA reconstruct? And what might these revelations tell us about our own future on a rapidly changing planet?To watch the full film, visit here.Learn more about NOVA and subscribe to our YouTube channel. 

Why Tropical Trees Don’t Have Rings | Kirk Johnson

Growth rings on trees can measure time, allowing scientists to date things from the deep past. But, paleobotantist Dr. Kirk Johnson explains why, in the tropics, some trees have no rings.For more, check out the extended interview with Kirk Johnson.Learn more about NOVA and subscribe to our YouTube channel. 

How Weight Loss Drugs Were Inspired by Gila Monsters | Sean B. Carroll

Nature has been solving problems for billions of years. Evolutionary biologist Sean B. Carroll reveals why scientists still turn to evolution’s inventions for life-saving breakthroughs, from GLP-1 drugs to statins.For more, check out the extended interview with Sean B. Carroll.Learn more about NOVA and subscribe to our YouTube channel.