(NaturalNews) New archaeological findings show that human beings were already deep-sea fishing at least 42,000 years ago, which is 30,000 years earlier than previously believed.
"All the bones we got inside were just the result of human meals, 40,000 years ago," said researcher Sue O'Connor of the Australian National University. "They were living in that shelter and we are fortunate that all the materials are preserved so well in that limestone cave, which preserves bone and shell really well."
Writing in the journal "Science," Australian and Japanese researchers recount their discovery of three fish hooks and almost 39,000 fish bones in a limestone cave in Jerimalai, East Timor. The cave is just 300 meters (985 feet) from the shore and 50 meters (165 feet) above sea level. Because all the hooks and bones were found in a single 1 meter (3 foot)-square "test pit", further excavation is likely to produce even more results.
The hooks were made from the shell of a large sea snail known as a Trochus.
"They are very strong shell ... we think they just put bait on and dropped the hook in the water from a boat (at the) edge of a reef," O'Connor said.
Although the archaeologists found bones from 23 different fish species, including emperors, groupers, parrotfish, snappers, trevallies, triggerfish and unicornfish, nearly half of all bones belonged to pelagic tuna fish.
And while the fish hooks found in the cave are only between 16,000 and 23,000 years old, the presence of so many fish bones from 42,000 years ago strongly indicates open-sea fishing.
"Parrotfish and unicorn were probably caught on baited hooks ... but tuna are deepwater, fast-moving fish," O'Connor said. "Tuna and trevallies were probably caught by lure fishing."
Clues to Our Past
Previously, the oldest evidence of open-sea fishing dated to only 12,000 years ago. Yet human beings were obviously able to traverse long oceanic distances at least 50,000 years ago, which is when they crossed from Asia to Australia. The new findings raise the possibility that the development of deep-sea fishing may have been one of the innovations that allowed humans to settle the remote islands out past New Guinea, such as the Solomon Islands.
Researchers do not know whether the fish hooks were being used in deep sea fishing or only in other types of fishing. It also remains to be seen whether the archaeologists will find any older fish hooks when they explore the site more fully.
"[The hooks] must have been attached with strong fiber lines of some kind, string, but we really don't know whether they were using this kind of fishing technology at 42,000 years ago," said archaeologist Chris Clarkson of the University of Queensland. "They may well have been out in boats with nets. They may have been spear fishing but certainly by sort of 20,000 years ago it seems that they were using strong, fiber lines and probably hand casting or dangling these fish hooks off the edge of some kind of boat."
Humans have been eating fish for at least 1.9 million years, since before the evolution of the species Homo sapiens. Scientists believe that the earliest humans caught fish by wading into freshwater streams and lakes and using only spears or other simple tools. According to researcher Kathlyn Stewart of the Canadian Museum of Nature, who was not involved in the study, the first ocean fishers probably used boats made from lashed together logs, and caught fish with nets and with fish hooks made from wood or shells. It is unknown how far out to sea these first fishing peoples ever ventured.