An orchestral symphony has a lot of instruments, but you tend to concentrate on the soloists. 

In this metaphor I see the soloists as mitochondrial and Y chromosome DNA going right back through the maternal and Y chromosome DNA. But against a background of the symphony all the other pieces of the orchestra are playing as well. And up until the last couple of years we couldn't really hear what they were playing.

But because of the developments and the analysis of the chromosomes other than the Y and mitochondria we can now begin to pick out that music from the symphony background.  

60 Second Reads is recorded in Big Think's studio.

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