IANS

Washington, Jul 7:  Freshwater fish remains a staple in many regions of the world, but it remains unclear when it became a year-round diet for early humans. A new study led by Erik Trinkaus, anthropology professor at Washington University, St. Louis, shows it may have happened in China as far back as 40,000 years ago.

Chemical analysis of collagen, a protein, can show whether such fish consumption was an occasional treat or a regular food item.

Analysis of a bone from one of the earliest human's in Asia, the 40,000-year-old skeleton from Tianyuan Cave near Beijing, has shown that at least this individual was a regular fish eater.

This analysis provides the first direct evidence for the substantial consumption of aquatic resources by early modern humans in China, said a Washington University release.

Since this occurred before there was consistent evidence for effective fishing gear, the shift to more fish in the diet likely reflects greater pressure from an expanding population at the time of modern human emergence across Eurasia.

The study has been published online in the Proceedings of the National Academy of Sciences.