Researchers find oldest evidence of salmon consumption

FAIRBANKS, Alaska, Sept. 22 (UPI) -- Omega-3 fatty acids aren't a fad. Humans have been getting their fair share of fish oil for thousands of years -- 11,500 years, to be exact.

That's the age of chum salmon bones found by a team of researchers in Alaska, the earliest-yet evidence of salmon fishing. The sea-run chum salmon bones were found in an ancient cooking hearth among the remains of an Ice Age settlement, once home to Paleoindians.

Researchers published their findings in the journal Proceedings of the National Academy of Sciences.

"Salmon fishing has deep roots, and we now know that salmon have been consumed by North American humans at least 11,500 years ago," lead study author Carrin Halffman, an anthropologist at the University of Alaska Fairbanks, said in a press release.

DNA analysis confirmed that the salmon bones came from sea-run salmon, not landlocked fish.

"We have cases where salmon become landlocked and have very different isotopic signatures than marine salmon," explained study co-author Ben Potter. "Combining genetic and isotopic analyses allow us to confirm the identity as chum salmon, which inhabit the area today, as well as establish their life histories. Both are necessary to understand how humans used these resources."

These salmon traveled nearly 900 miles upriver from where the mouth of the Yukon now sits.

Because fish bones are so fragile, they don't preserve well, and many scientists believe their remains are underrepresented in the story of early human history. The latest discovery suggests fishing may have played an important role in the first colonization of North America by early peoples from Eurasia.