This is a stemmed bowl used for serving food. This type of vessel emerged during the Yayoi Period, when wet-rice agriculture began in Japan. As people shifted to a rice-centered diet, pottery also changed. Three new types of vessel appeared on the scene: pots for cooking, jars for preserving food, and stemmed bowls for serving food. Pottery was fired at higher temperatures in the Yayoi period, so Yayoi earthenware is harder and redder than its Jomon predecessor. Furthermore, the potter's wheel came into use during the mid-Yayoi period, so vessels from this era display a neat, undistorted roundness when viewed from above.The mouth of the bowl is decorated with a neat, evenly-spaced comb-tooth pattern. This also provides evidence that a potter's wheel was used. Pots, jars, and stemmed bowls from the early Yayoi period are collectively known as Ongagawa-style pottery after the river in Fukuoka Prefecture, where many of them were found. Ongagawa-style vessels have been found in a number of regions stretching from Kyushu to Kanto. This suggests rice farming culture spread across the Japanese archipelago.