After entering the Neolithic Period, people in Taiwan still continued to fish and hunt, but they also developed agriculture. Besides rhizome crops, such as taro and yam, people also started cultivating grains, like millet and rice, roughly 5,000 years ago. As food became more plentiful and reliable, people had the ability to develop more complex, refined aspects of culture, such as religion and craft. At the same time, the interactions among distant communities became more frequent. This can be seen from the cultural relics unearthed throughout Taiwan, such as jade ornaments that were produced exclusively in Hualien, while basalt products from Penghu have been found on the southwest coast. This shows that goods not only travelled all across the main island of Taiwan, but also to the offshore islands.