Main content
                
    Why your family tree isn’t written in your DNA
Genetic material is lost as it passes down the generations; we don’t inherit DNA from all our ancestors. So as we go back through time, our actual family tree and our genetic family tree diverge.
(Image: A family on a hillside with a tree in the background Credit: Getty Images)
Duration:
This clip is from
Featured in...
![]()  - Why you are the way you are—CrowdScience- What's going on when we want to pee and why are we embarrassed to be naked? 
More clips from CrowdScience
- 
                                                ![]()  What would happen if we fell straight through the earth?Duration: 02:34 
- 
                                                ![]()  Why is aurora green?Duration: 02:19 
- 
                                                ![]()  In a random universe, is anything predictable?Duration: 01:58 
- 
                                                ![]()  How do birds survive so high up?Duration: 02:13 
 
         
             
 
             
             
            