While the sites of the early ceramic period (ca. 1500-500 B.C.) are few, small and difficult to locate (not a single complete vessel is known), the period between roughly 400 B.C. until 400 A.D. was a major watershed in Costa Rican prehistory, witnessing a dramatic increase in sites and population, coupled with a trend towards social stratification.

In terms of sociopolitical organization, this time span marked the first appearance of what anthropologists call chiefdoms, which cover a range of complexity between simple egalitarian bands and highly structured political states like the Aztec or Inca. In Costa Rica, chiefdoms seemed to have been made up of several thousands of people and encompassed thousands of square miles in some cases. Power, status and wealth were at least partially hereditary, and there was a virtual explosion of fancy artifacts that were intrinsically ceremonial in nature or sometimes symbolic of rank and high status.

Trade and exchange systems some were long-distance, sea-going routes become more important, and it was during this period that the three major archaeological culture zones in Costa Rica became clearly differentiated: Guanacaste-Nicoya, the drier NW quarter of the country; the Central Region, which includes the Central Valley and the Central Atlantic and Pacific Watersheds (the northeast and southeast corners of Costa Rica are still little-known archaeologically); and Diquis, the southwest quadrant of the country.

For archaeologists, Diquis, always more southern-oriented, is part of the Greater Chiriqui Region, which includes the Panamanian province of that name, and Guanacaste-Nicoya, always more northern-oriented, is part of the Greater Nicoya Region, including the Rivas sub-region of Nicaragua. Obviously, modern national frontiers were nonexistent in prehistoric times.

Agriculture and Ceramics

Agriculture was being practiced in some form about 2,000 years before the key period discussed here, but its effects of rising population, the tendency of people to stay longer in one place (sedentism) and the greater size of archaeological sites did not become apparent before 400 B.C. The type of agriculture associated with this period is known as slash-and-burn or swidden agriculture, which involves cutting down trees and clearing enough ground for planting, usually quite near the settlement itself. After a few generations, soil fertility decreases and new agricultural plots as nearby as possible are sought.

Over hundreds of years, this shifting pattern results in cultural remains being scattered over a large area. If the remains include virtually non-perishable materials such as fired pottery, stone tools and charcoal (chemically inert), then a treasure trove of information awaits the archaeologist.

Given these circumstances, archaeologists in the 1950s and 1960s were able to identify and date sites and pottery with the Carbon-14 technique to the several centuries before and after Christ (C-14 or radiocarbon dating had only been developed a decade or so before). This was the oldest known pottery known in Costa Rica until 1977, when I discovered and dated the La Monta�a ceramic complex to 1,000 years earlier.

But in the Central Valley (Pavas complex) and especially the Central Atlantic Watershed (El Bosque complex), pottery made from roughly 2,400 to 1,600 years ago is remarkably common and widely distributed. Indeed, in these subregions it is rather rare for archaeologists to excavate more recent sites without encountering Pavas or El Bosque complex pottery fragments as past of the soil matrix. The very high quality of the pottery and other artifacts produced during this time span suggest that it was a long, relatively peaceful period during which sociopolitical and religious complexity germinated and flowered.

The dramatic increase in the amounts of pottery produced during the 400 B.C. 400 A.D. period can be said to correlate positively with greater (and more productive) agriculture (carbonized maize, beans and palm nuts are the foodstuffs most often found by archaeologists) simply because ceramic vessels were used extensively in the processing, cooking and storage of agricultural products, as well as to hold water and other liquids.

Most pottery vessel forms can be classified as culinary/storage, such as large globular and ovoid jars and large plates (often with soot and carbon deposits), and serving vessels, such as bowls, dishes, and cups.

In all parts of Costa Rica, most pottery of this time period was made with two distinct zones of color, usually a hard, brightly polished red slip over the rims, bases and sometimes interiors of lighter color of the natural fired clay; this is often called red-on-bluff ware, and it predominated in the Central Atlantic Watershed and Diquis (Aguas Buenas complex). It is also common in the Central Valley and Guanacaste-Nicoya, but in the former zones of maroon paint contrasting with an orange slip are more frequent, while in the latter designs in black mineral paint are outlined by engraved lines. Modeled, appliqu�, stamped, and incsed decorative techniques were widely used throughout the country during this time period.

Ritual, Ceremony, and Human Sacrifice

But it was also during this period that special-purpose pottery vessels and other ceramic objects began to appear with increasing frequency. These included long-legged tripod vases with ornate decoration, but often with soot deposits as well. This implies their use in the ritual or ceremonial preparation of foodstuffs or other substances, almost certainly including fermented, soupy beers of maize, peach palm, or other cultigens, and psychotropic potions of any number of trance-inducing or mood-altering plants found in the tropical rainforest. That some of the latter were also smoked or inhaled is suggested by the appearance of carefully crafted ceramic pipes and double-tube nasal snuffers.

Rituals and ceremonies accompanied by music are indicated by finds of ceramic maracas, both single-finger and hand-held, and a huge variety of whistles, flutes and ocarinas, almost all of which are decorated with human figures costumed with elaborated headdresses and masks (drums were surely present too, but were probably made of organic materials, thus not preserved). Ceramic stamps for body painting appear for the first time. Certain larger ocarinas even display scenes from the rituals themselves, such as for men carrying another on a litter, men and women copulating, and men holding another prone while a masked figure cuts open his chest. The details of clothing, costumes and customs displayed by these kinds of figurines (many served as rattles, too) is simply amazing, and a comprehensive study remains to be done.

Ceramics like these were not possessed or used by everyone, and, although they look to us like toys, tend to be found in the greatest numbers as grave goods in high-status tombs. Culinary and serving vessels are also found in tomb offerings, frequently with one inverted over another; they undoubtedly held food and drink for the deceased in the afterlife. I have excavated many tombs of this period in the Central Atlantic Watershed, which are rectangles and even longer corridors of stone river cobbles.

The houses or domiciles that are best preserved defined by fired adobe floors in the Central Valley and lines of stone cobbles as foundations in the Atlantic Watershed are also usually rectangular. Tombs may be found beneath and around a house, or in separate cemetery zones.

One tomb beneath a large house 2,000 years old near the modern town of Guacimo on the Old Line railroad contained 27 fancy artifacts, among them flutes, maracas, elaborate vessels, the plate of ceremonial stone metate, and a necklace of jade beads. It is fascinating that the skillful stone sculpture of this time was almost always incorporated into a metate or grinding table, high-status ceremonial objects used in rituals to propitiate agricultural deities.