CARDIFF, WALES—Cardiff University announced that researcher Philip Staudigel and his colleagues at the University of Miami and Valencia College studied possible cooking techniques used by the first residents of the island of Puerto Rico some 2,500 years ago. The scientists employed a type of chemical analysis known as clumped isotope geochemistry to analyze some 45 pounds of fossilized clamshells, and found that some of the shellfish were exposed to high heat, as if they had been barbecued, rather than boiled in water at a lower temperature. Staudigel suggests that pottery technology, which would have been necessary for boiling the clams in water, may not have been in widespread use. Some of the clams had been exposed to lower levels of heat, he added. They may have been placed on top of clams that had been placed directly over cooking fires. To read about a cave on an island west of Puerto Rico that contains both Taino and European inscriptions, go to "Spiritual Meeting Ground," one of ARCHAEOLOGY's Top 10 Discoveries of 2016.