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    NOVA
            NOVA Wonders What's Living in You?
                
                    
                        
                            Season 45
                        
                    
                    
                        
                            Episode 102
                        
                    
                
            
            
            Whether they make you fat, fart, or freak out, microbes play a central role in your life. Right beneath your nose—on your face, in your gut, and everywhere in between—trillions of bacteria, viruses, and fungi are so abundant in your body, they outnumber your human cells. But these aren’t just nasty hitch-hikers. Many are crucial to your survival.
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            Find out why deadly flash floods are on the rise and how we can protect ourselves from them.
        
        
     
    
                        
  
  
    
      
    
  
  
    
      
        
          53:21
        
      
    
  
  
                    
                
            Explore mysterious 9,000-year-old Stone Age megastructures found in the Arabian Desert.
        
        
     
    
                        
  
  
    
      
    
  
  
    
      
        
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            Discover how two revolutionary ancient inventions changed the course of humanity forever.
        
        
     
    
                        
  
  
    
      
    
  
  
    
      
        
          53:25
        
      
    
  
  
                    
                
            Follow ancient humans’ journey into an icy and perilous new land.
        
        
     
    
                        
  
  
    
      
    
  
  
    
      
        
          53:27
        
      
    
  
  
                    
                
            Discover how Homo sapiens outlasted Neanderthals – and how they helped make us who we are today.
        
        
     
    
                        
  
  
    
      
    
  
  
    
      
        
          53:25
        
      
    
  
  
                    
                
            Follow Homo sapiens as they venture out of Africa and spread farther than any other human species.
        
        
     
    
                        
  
  
    
      
    
  
  
    
      
        
          53:32
        
      
    
  
  
                    
                
            Trace the remarkable origin story of Homo sapiens and the crucial moments that shaped our species.
        
        
     
    
                            
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          53:27
        
      
    
  
  
                    
                
            Forensic science is put to the test after the first-ever staged multi-vehicle pileup.
        
        
     
    
                            
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          53:29
        
      
    
  
  
                    
                
            A first-of-its-kind experiment aims to stage a multi-vehicle pileup to gain new data on car safety.
        
        
     
    
                        
  
  
    
      
    
  
  
    
      
        
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            After centuries of pseudoscience, researchers examine the causes of racial health disparities.
        
        
     
    
                            
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          53:41
        
      
    
  
  
                    
                
            Follow scientists in a quest to understand how complex forest ecosystems can help cool our planet.
        
        
     
    
                            
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          53:39
        
      
    
  
  
                    
                
            Explore key military technologies in the American colonies’ fight for freedom.
        
        
     
     
     
     
     
     
     
     
     
     
     
    