section_path: Global trends/Trade and communication
section_name: Trade and communication
paragraph_text: Trade and communication
  
  Finally, communication and trade across Afro-Eurasia increased rapidly. The Silk Road continued to spread cultures and ideas through trade. Communication spread throughout Europe, Asia, and Africa. Trade networks were established between western Europe, Byzantium, early Russia, the Islamic Empires, and the Far Eastern civilizations. In Africa, the earlier introduction of the camel allowed for a new and eventually large trans-Saharan trade, which connected Sub-Saharan West Africa to Eurasia. The Islamic Empires adopted many Greek, Roman, and Indian advances and spread them through the Islamic sphere of influence, allowing these developments to reach Europe, North and West Africa, and Central Asia. Islamic sea trade helped connect these areas, including those in the Indian Ocean and in the Mediterranean, replacing Byzantium in the latter region. The Christian Crusades into the Middle East (as well as Muslim Spain and Sicily) brought Islamic science, technology, and goods to Western Europe. Western trade into East Asia was pioneered by Marco Polo. Importantly, China began to influence regions like Japan, Korea, and Vietnam through trade and conquest. Finally, the growth of the Mongol Empire in Central Asia established safe trade which allowed goods, cultures, ideas, and disease to spread between Asia, Europe, and Africa.
  
  The Americas had their own trade network, but here trade was restricted by range and scope. The Mayan network spread across Mesoamerica but lacked direct connections to the complex societies of South and North America, and these zones remained separate from one another.
  
  In Oceania, some of the island chains of Polynesia engaged in trade with one another. For instance, with outrigger canoes long-distance communication of over 2,300 miles between Hawaii and Tahiti was maintained for centuries before its disruption and separation. Meanwhile, in Melanesia there is evidence of exchanges between mainland Papua New Guinea and the Trobriand Islands off its coast, most likely for obsidian. Populations moved westward until 1200, after which the network dissolved into much smaller economies.