1450-1778 the pace of construction of heiau slowed dramatically as did the clearing of agricultural land. Accordingly, the estimated population in 1778 around Cook's arrival was between 110,000 and 150,000. Eastern contact Pre-Western contact syphilis James Cook may not have been the first outsider to visit Hawaii. Diseases to which Hawaiians lacked immunity may well have already been spread. Testing of a young woman's bones buried in O'ahu, dated sometime between 1422 AD and 1664 according to radiocarbon dating, indicated that she had congenital syphilis, a disease which can leave a variety of distinctive marks on bone. Syphilis has long been surmised to have originated in the American Hemisphere, and to have been imported into Europe, following the return of Europeans from Columbus's first voyage in 1494 in Naples Italy, where its first European appearance was first recorded. That postulation is an established part of the Columbian exchange. That supposition of an American origin has, however, been recently challenged, and is being further evaluated by historians of disease, who argue that its presence in Europe may not have been detected previously. Another possible explanation for syphilis in the pre-Cook era finds reference to traditional Hawaiian accounts of foreign shipwrecks as well as the presence of metal blades seen by James Cook upon landing in Kaua'i, later presumed to be from Japanese sailors. Syphilis was introduced to Japan around 1512 by mariners who had contracted the disease while in China. By 1600, approximately 39.4% of Japanese men had contracted syphilis. Shipwrecks Hawaiian tradition does not record the nationalities of the shipwrecks on Maui in Kiwi, Kona in Hawaii or Kauai (legend has it they cohabited and had children with Hawaiians) except to characterize them as white people arriving between years 1521 and 1530 AD. Many scholars, however, believed them to be Spanish. Records of Japanese sailors that were transmitted to their homeland during the Kamakura period state that Japanese boats landed at Makapu'u Point on the island of O'ahu in the year 1258. Further, in 1270, a separate group of Japanese sailors carrying sugar cane went ashore at Kahului, Maui. Metal blades seen by James Cook in Kaua'i There are many parallels between Hawaiian and Japanese cultures; the similarity of Japanese knives to iron blades in the possession of Hawaiians at the time of Cook's first landing at Kaua'i is a prime example. These were thought to have developed through cultural