Adam Rutherford gives us a fascinating tour of what genetics tells us about the history of our species, including the close relatives with whom we interbred, the Neanderthals and Denisovans.
New discoveries show the first H. Sapiens left Africa even earlier than we previously thought, and didn't always take the paths we assumed. Our DNA tells us a great deal about ourselves as a species, but not nearly as much as we like to imagine about ourselves. There just isn't that much diversity in the genome of H. Sapiens, and most of what there is, is among the peoples of Africa. The rest of us haven't been gone from Africa long enough, or separated from each other long enough, to produce that much genetic variation.
Experience and environment have far more to do with who we are as individuals than merely our genes, although some of that experience gets passed along to the next generation or two in the form of a relatively new discovery: epigenetics. Extreme or intense experiences, such as drought or famine, seem to affect how genes get activated and expressed in the next couple of generations after the one that experienced the stress.
The real secrets revealed by our genome are the secrets of our history as a species, including what we did when we met other members of genus homo who looked, and acted, "close enough." Specifically, there seems to have been an awful lot of sex, whether our ancestors met other H. Sapiens, or Neanderthals, or Denisovans (or possibly other close relatives that we're only just starting to discover.) We exchanged genes, and some of those "alien" genes are still in our genome.
In many ways, the most interesting aspect of this is what our genome tells us about the paths of human migration as H. Sapiens spread out from Africa, and Rutherford tells the story very well.
Recommended.
I bought this audiobook.
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