It may be a global practice that accounts for a large percentage of protein consumption in many countries, but fishing is perhaps the least intuitive way to get food — most of the time, you can’t even see what you’re looking for.

Hunting and gathering make sense, dealing as they do with the terrestrial realm in which we landlubbers evolved. We’re all familiar with this part of our heritage: Early humans got by spearing mammoths and foraging wild plants. Yet fishing also has ancient roots, as revealed in recent decades, by archaeological discoveries from around the world.

Did Our Ancestors Fish?

It’s impossible to say precisely when our ancestors began hauling fish out of the water. If they started by snatching prey from the shallows with their bare hands, no tools would remain to prove it. And any leftover food scraps, of course, would have been biodegradable.

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Nevertheless, the oldest solid evidence of hominins eating aquatic creatures comes from northern Kenya. That’s where archaeologists uncovered hundreds of bones from butchered animals, including turtles, crocodiles, and catfish according to a study published in the journal Anthropology in 2010. Those specimens date to just under 2 million years ago, long before modern humans arrived on the scene, and it’s unclear which species was responsible for the animals’ demise.

Clearly, though, fishing arose in our predecessors (like Homo erectus and Homo ergaster), some of whom are known to have been hunters. It’s even possible, as the researchers involved in the 2010 study suggest, that the omega-3 and omega-6 fatty acids in fish “could have played an important role in the evolution of larger brains in the early history of our lineage.”

Even if its precise origin is uncertain, we’re no doubt dealing with a tradition that has developed gradually over a long, long time — not one that some innovator conjured out of thin air in the recent past.

“No one ‘invented’ fishing,” writes Brian Fagan, a professor emeritus of anthropology at the University of California, Santa Barbara, in Fishing: How the Sea Fed Civilization. “Everyone knew fish were there for the taking at specific times and places.”

Did Early Humans Fish?

As for our own species, the earliest evidence comes from Tianyuan Cave, near Beijing. In 2009, a team led by Chinese researchers analyzed 40,000-year-old human remains from the cave. High levels of nitrogen isotopes, which are helpful for determining what ancient people ate, led them to conclude that “a substantial portion of [their] diet” came from freshwater fish. Our forebears hadn’t just begun to get their calories from fish; they’d made it a staple.

Lakes and streams are one thing, but what about the ocean? Based on another site from roughly the same period, it seems that seafaring cultures were also reeling in pelagic fish, like tuna, swordfish and mackerel, which swim far beneath the surface and likely required more sophisticated techniques to catch.

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In 2011, in an East Timor cave called Jerimalai, archaeologists found thousands of bones from tuna, sharks, rays and other pelagic fish. Like the remains from Tianyuan, they too date to about 40,000 years ago, and were almost certainly brought there by humans.

What’s more, the team found what was at that point the oldest known fish hook, carved from a piece of mollusk shell. Granted, it came from a younger layer of the excavation, but still boasted a remarkable age between 16,000 and 23,000 years old. A few years later, in 2016, Japanese researchers working on the island of Okinawa discovered more hooks of similar age and origin — around 23,000 years old and manufactured from the shells of sea snails.

When Did Humans Start Sailing the High Seas?

This all fits with what we know of humanity’s progression toward maritime mastery. It seems humans had blossomed into advanced ocean-goers much earlier: Around 50,000 years ago, they’d reached many of the Southeast Asian islands, not to mention Australia, a voyage requiring some 50 miles of sailing across open water.

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Though the settlement of Australia remains hotly debated, many experts believe that to make the trip, Indigenous Australians must have been capable of long-distance sea travel (as opposed to having drifted there accidentally). If so, it’s possible they were casting lines or nets along the way, especially considering those nearby deep-sea fish bones in Timor.

Fishing Throughout the Centuries

Zooming out further, the past 50,000 years account for only a fraction of the history of Homo sapiens. Humans have lived along coastlines for much longer, and though it’s unclear what role fishing may have played in that remote era, some evidence suggests they took advantage of marine resources well before Jerimalai and Tianyuan.

In 2007, an international team of researchers found shells of mussels, abalone and other invertebrates in a cave on the southern coast of South Africa, perhaps harvested during famines in that harsh environment. They’re approximately 160,000 years old, illustrating just how ancient the connection is between humans and their underwater neighbors.

In the ensuing millennia, that bond changed dramatically. Fishing spread far and wide, evolving into the diverse disciplines we see today — from angling to trawling, recreational to industrial. Indeed, of the three pre-agricultural methods for acquiring food (the other two being hunting and gathering), it’s the only one that still feeds people on a significant scale.

That said, the astronomical growth of commercial fishing in modern times has resulted in severe overexploitation, leading to population declines and biodiversity loss on a devastating scale. This is a problem not only for animals and ecosystems, but also for the communities who rely on them.

For better or worse, we’ve come a long way since our ancestors hung the first “Gone Fishing” sign.

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