Did you know? Age of oldest musical instrument (42,000 y) is 4 x Time since first domestication of cattle (10,500 y)
Age of the earliest city (6,500 y)
/fact/age-of-the-earliest-city
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If this was a standard unit ...
Yes, there's now a book based on these numbers. Oxford University Press: July 2018.
Click here to learn more about it.
Click here for Podcast: Andrew Elliott interviewed for New Books Network.