As a cultural area, Mesoamerica is defined by a mosaic of cultural traits developed and shared by its indigenous cultures. Beginning as early as 7000 BC, the domestication of cacao, maize, beans, tomato, avocado, vanilla, squash and chili, as well as the turkey and dog, caused a transition from paleo-Indian hunter-gatherer tribal grouping to the organization of sedentary agricultural villages. In the subsequent Formative period, agriculture and cultural traits such as a complex mythological and religious tradition, a vigesimal numeric system, and a complex calendric system, a tradition of ball playing, and a distinct architectural style, were diffused through the area. Also in this period, villages began to become socially stratified and develop into chiefdoms with the development of large ceremonial centers, interconnected by a network of trade routes for the exchange of luxury goods, such as obsidian, jade, cacao, cinnabar, Spondylus shells, hematite, and ceramics. While Mesoamerican civilization did know of the wheel and basic metallurgy, neither of these technologies became culturally important.
Among the earliest complex civilizations was the Olmec culture, which inhabited the Gulf coast of Mexico and extended inland and southwards across the Isthmus of Tehuantepec. Frequent contact and cultural interchange between the early Olmec and other cultures in Chiapas, Guatemala and Oaxaca laid the basis for the Mesoamerican cultural area. All this was facilitated by considerable regional communications in ancient Mesoamerica, especially along the Pacific coast.