burials with Panama’s first radiocarbon date (4860 ± 110 b.c.). Later a date of 2090 ± 70 b.c. was obtained on charcoal from the Monagrillo type-site (He-5). Willey and McGimsey inferred that preceramic and ceramic populations were preagricultural hunter-fisher-gatherers with a littoral focus. Their macroscopic analysis of sediments and the distribution of shell species through time spawned an accurate model of coastal progradation and habitat use.

The amateur Isthmian Archaeology Society became active in the 1950s, and some of its members wrote careful reports. At Playa Venado hundreds of graves were excavated, some under Lothrop’s guidance. A few contained gold jewelry, whose social and temporal contexts were usually not revealed. Lothrop’s contention that some skeletons were mutilated and sacrificed requires verification by modern bio-anthropology. In 1998 Luís Sánchez compared Playa Venado pottery in U.S. museums to samples excavated in the 1990s at Cerro Juan Díaz and confirmed that most of Playa Venado’s polychrome pottery corresponds stylistically to the Cubitá (a.d. 500–750) and Conte (a.d. 700–850) styles of the Gran Coclé semiotic tradition. Shell and bone jewelry and burial practices have close parallels at Cerro Juan Díaz for the same time period. Contact among littoral populations around Panama Bay appears to have been strong from about a.d. 500 to 850, when Spondylus shell was an important exchange commodity.

In the 1960s archaeologists’ opinions about external connections were influenced by james ford’s formative paradigm, which argued for constant contact among American littoral populations (Ford 1969). One result of this mode of thought was the Interrelationships of New World Cultures project, whose Panama Pacific branch was directed by McGimsey, accompanied by the Panamanian Olga Linares. In 1961 sixty sites along the Chiriquí coast and islands were recorded, twelve of which were tested. In the late 1950s and early 1960s Wolfgang Haberland studied Chiriquí mortuary sites and described their pottery. Linares established three ceramic phases for the Gulf of Chiriquí, from about a.d. 300 to 1520. The following year researchers from the program tested sites in the Gulf of Montijo and the Darién, including deep shellmounds at Mariato.

The “New Archaeology” convinced Linares that research in the Neotropics should be more than Fordian seriation based on arbitrary stratigraphy. She designed a multidisciplinary program for testing hypotheses concerning the origins, dispersal, and economies of the past and present Native Americans of Panama and costa rica. Archaeological sediments were sieved, excavations followed natural stratigraphy, and features were cleared. Systematic surveys used subsurface testing. Linares chose three regions with contrasting ecologies—the Aguacate Peninsula on the Caribbean coast, the environs of the 3,400-meter-high Barú volcano, and the central Chiriquí coast. Anthony J. Ranere’s simultaneous discovery of preceramic deposits (dated to 4600–350 b.c.) at four Pacific-side foothill rock shelters showed that not all small-scale preagricultural peoples in tropical America were coastal. He proposed the “Tropical Forest Archaic” as an alternative to Willey’s “Northwestern South American Littoral Tradition,” which then included Cerro Mangote and Monagrillo (He-5) (Linares and Ranere 1980; Ranere 1975; Willey 1971).

Linares hypothesized that maize-based agriculture developed originally in the Pacific foothills and spread to the Pacific highlands, coast, and islands in the first millennium b.c. (Linares 1977a). Her own surveys—and Catherine Shelton’s later survey in the Chiriquí Viejo and Chiriquí Rivers—indicated that highland farming villages coalesced into two territories dominated in the lower chiefdom by Barriles and in the upper one by Sitio Pittí. Volcanic ash atop house features at Sitio Pittí from a.d. 300 indicated that an eruption caused the abandonment of settlements in the upper chiefdom but occupation continued around Barriles (Linares, Sheets, and Rosenthal 1975). Excavations at Cerro Brujo on the Caribbean coast revealed two occupations. Pottery modes in the thin basal level were similar to those manufactured on the Pacific slopes between about a.d. 400 and 600. Linares therefore surmised that highland peoples migrated to the western Caribbean coast at this time; subsequently, settlement patterns, material culture, and subsistence