2221정승현

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From Treasure Hunting to Laboratory Science: The Development of Archaeological Excavation

For most of its history, digging up the past was not a science at all. Renaissance and early modern antiquarians collected statues, coins, and inscriptions much as they collected butterflies. When Pompeii was first explored in the 1740s, workers tunneled toward paintings and bronzes and discarded the plaster, pottery, and burnt wood that lay between them. The object was the prize; the dirt around it was an obstacle. Almost everything archaeologists now consider evidence was thrown away.

The first conceptual break came from geology. Nicolas Steno's principle of superposition — that lower layers were deposited before upper ones — gave excavators a way to read time directly out of the ground. Thomas Jefferson applied something like this logic in 1784, cutting a trench through a burial mound in Virginia and describing the distinct layers he passed through rather than simply emptying it. His report is often called the first scientific excavation, though the method took another century to become standard practice.

That standardization was largely the work of two men. General Augustus Pitt-Rivers, excavating on his English estate in the 1880s and 1890s, insisted that ordinary potsherds and animal bones be recorded as carefully as gold, that every find be located in three dimensions, and that results be published in full whether or not they were exciting. Flinders Petrie, working in Egypt at the same time, developed sequence dating: by arranging pottery from hundreds of graves according to gradual changes in form, he built a relative chronology for periods that had no written records. This technique, later formalized as seriation, showed that patterns in mundane artifacts could carry more information than any single spectacular object.

In the twentieth century, excavation itself became a controlled procedure. Mortimer Wheeler popularized the box-grid system, leaving standing sections of earth between excavated squares so the stratigraphy remained visible and verifiable throughout the dig. Kathleen Kenyon adapted this approach at Jericho, using deep vertical sections to untangle thousands of years of superimposed occupation. The underlying principle was uncomfortable but essential: excavation destroys its own evidence. A site can be dug only once, so the record — plans, sections, photographs, notes — becomes the permanent object of study.

The decisive change arrived from physics. In 1949, Willard Libby demonstrated radiocarbon dating, which measures the decay of carbon-14 in organic material and yields absolute dates independent of artifact styles or historical texts. Its effects were immediate and disruptive. Chronologies built on the assumption that innovations spread outward from the Near East collapsed when European megalithic tombs proved older than the Mediterranean structures they supposedly imitated. Other clocks followed: dendrochronology, developed from A. E. Douglass's tree-ring work, allowed calibration of radiocarbon results to the calendar year; potassium-argon dating pushed human origins research back millions of years; thermoluminescence dated fired ceramics and heated stone.

Meanwhile, the questions archaeologists asked were widening. The processual archaeology of the 1960s, associated with Lewis Binford, argued that the discipline should explain how past societies functioned rather than merely describe what they left behind. This demanded new kinds of data, and new recovery methods produced them. Flotation — washing excavated soil to separate carbonized seeds — turned agriculture into something observable. Pollen cores reconstructed ancient vegetation and climate. Microscopic wear traces on stone tools revealed what those tools had actually cut.

Recent decades have added two further dimensions. The first is the ability to see sites without digging them. Aerial photography, magnetometry, ground-penetrating radar, and above all airborne LiDAR have mapped buried and forest-covered landscapes at a scale no excavation could reach; LiDAR surveys in Cambodia and Guatemala revealed urban networks around Angkor and in the Maya lowlands that had gone unrecognized for a century. The second is molecular archaeology. Stable isotopes in teeth and bone indicate where an individual grew up and what they ate. Ancient DNA, pioneered in Svante Pääbo's laboratory, has sequenced Neanderthal genomes, identified the previously unknown Denisovans from a fingerbone fragment, and traced prehistoric migrations that pottery typologies could never have detected. Proteins and DNA can now be recovered from dental calculus and even from cave sediments containing no bones at all.

The trajectory is consistent. Archaeology has moved from valuing objects to valuing context, from relative to absolute chronology, and from asking what people made to asking how they lived, moved, and were related. It has also grown more cautious. Because every method still under development will need material to work on, many archaeologists now argue for excavating less rather than more — leaving sites intact for techniques that do not yet exist.