I thought this..
"Only 5 of the 137 mummies were Unangan. The rest were agricultural. Since the mid 1700's, the Unangan lived under Russian rule and hunted only otters for their hides. By the time the Unangan mummies died, 1850 to 1900, they had been relying on trade goods for at least 100 years."
all were agricultural except for 5 who most likely got lots of wheat and sugar from the Russians. The mummy study says nothing about non-ag peoples.
An optimist is someone who falls off the Empire State Building, and after 50 floors says, 'So far so good!'