Fish hooks found in a cave in Okinawa, Japan, are believed to be the oldest ever discovered, dating back some 23,000 years and showing how fishing technology developed earlier than previous thought.
The research, which was published last week in the Proceedings of the National Academy of Sciences Journal, stated that the fish hooks were made from the shells of sea snails, according to The Guardian. The hooks were found in the Sakitari cave, a limestone cave where scientists have conducted excavations since 2009.
"Well-stratified strata at the Sakitari cave site yielded a rich assemblage of seashell artifacts, including formally shaped tools, beads, and the world's oldest fish hooks," the PNAS study said in its abstract section. "These are accompanied by seasonally exploited food residue."
"The persistent occupation on this relatively small, geographically isolated island, as well as the appearance of Paleolithic sites on nearby islands by 30,000 years ago, suggest wider distribution of successful maritime adaptations than previously recognized, spanning the lower to midlatitude areas in the western Pacific coastal region," the study continued.
The study's co-author, Masaki Fujita, the curator at Okinawa Prefectural and Art Museum, told CNN that it was maritime technology that allowed the human race to spread throughout the world. Fujita said that, while humans were first believed to have crossed to Australia about 50,000 years ago, evidence only existed that the maritime adaption was only from Australia to Wallacea, a group of mainly Indonesian islands.
"Our findings suggest that Paleolithic people had adapted their maritime technologies to live not only in Wallacea and Australia, but a much wider geographic zone," Fujita told CNN.
"We found fish and human bones that dated back some 30,000 to 35,000 years. We don't know what kind of tools were used to catch these fish, but we're hoping to find some even older fishing tools," Fujita added.