cattle, were introduced to the island around 1000 CE by settlers from east Africa, who also brought sorghum, goats, possibly Bambara groundnut, and other food sources. Because these cattle represented a form of wealth in east African and consequently Malagasy culture, they were eaten only rarely, typically after their ritual sacrifice at events of spiritual import such as funerals. Fresh zebu milk and curds instead constituted a major part of the pastoralists' diet. Zebu were kept in large herds in the south and west, but as individual herd members escaped and reproduced, a sizable population of wild zebu established itself in the highlands. Merina oral history tells that highland people were unaware that zebu were edible prior to the reign of King Ralambo (ruled 1575–1612), who is credited with the discovery, although archaeological evidence suggests that zebu were occasionally hunted and consumed in the highlands prior to Ralambo's time. It is more likely that these wild herds were first domesticated and kept in pens during this period, which corresponds with the emergence of complex, structured polities in the highlands. Foods were commonly prepared by boiling in water (at first using green bamboo as a vessel, and later clay or iron pots), roasting over a fire or grilling over hot stones or coals. Fermentation was also used to create curds from milk, develop the flavor of certain dried or fresh tubers or produce alcoholic beverages from honey, sugar cane juice or other local plants. The techniques of sun curing (drying), smoking and salting were used to preserve various foods for transport, trade or future consumption. Many foods prepared in these ways, such as a smoked dried beef called kitoza () and salted dried fish, are still eaten in a similar form in modern-day Madagascar. By the 16th century, centralized kingdoms had emerged on the west coast among the Sakalava and in the Central highlands among the Merina. The Merina sovereigns celebrated the new year with an ancient Merina ceremony called the Royal Bath (fandroana). For this ceremony, a beef confit called jaka () was prepared by placing beef in a decorative clay jar and sealing it with suet, then conserving it in an underground pit for a year. The jaka would be shared with friends at the following year's festival. As a dessert, revelers would eat rice boiled in milk and drizzled with honey, a preparation known as tatao (). According