dust, smoke, and even tree canopy and soil and thus provide images for targets that cannot be seen with the other platforms.

These characteristics have proved to be of great value not only for the detection of archaeological features situated underneath a tree canopy or other covering but also for the detection of subsurface archaeological features. One SIR-A radar image made over the Sahara revealed a prehistoric river system located between one and four meters beneath the sand. Subsequent excavation yielded human artifacts dating back to the Paleolithic period and other archaeological data that indicated a moister environment.

The complex nature of the archaeological data, comprising cultural and environmental elements, requires archaeologists to take advantage of all the available methodological tools. With the changing emphasis in archaeological research, which has shifted from site-oriented problems to more-regional approaches, the adoption of remote sensing along with other new technologies such as geographic information systems makes perfect sense. Although still in its early stages, remote sensing provides an excellent means of gathering data that describe the biophysical context where human groups developed. The growing access to affordable computer power along with the increasing availability of satellite and radar images will soon consolidate the position of remote sensing as an essential component of the archaeologist’s tool kit.

Armando Anaya Hernández

See also

Crawford, O. G. S.; United States of America, Prehistoric Archaeology

References

Ebert, J.I. 1984. “5 Remote Sensing Applications in Archaeology.” In Advances in Archaeological Method and Theory 7:293–362. Ed. Michael B Schiffer. New York: Academic Press.

Lillesand, T. M., and R.W. Kiefer. 1991. Remote Sensing and Image Interpretation. 3d ed. New York: John Wiley and Sons.

Liverman, D., E.F. Moran, R.R. Rindfuss, and P.C. Stern. 1998. People and Pixels. Washington, DC: National Academy Press.

Rock Art

The study of rock art in all its various forms has no specific point of origin. Indeed, rock art was never really “discovered” at all with the obvious exceptions of caves blocked since the Ice Age, sites buried by deposits (which had to be excavated), and areas no longer frequented by humans (deep jungle, remote desert). Local people always knew the rock art was there, often believing it to be the work of devils, evil spirits, sorcerers, or fairies, and would sometimes point it out to visiting explorers or scholars. Most early “scholarly discoveries” of rock art came about accidentally as traveling missionaries or explorers reported on anything of interest that they encountered.

It was not until the late ninteenth or early twentieth century that systematic searches for rock art began. Naturally, early reports had no concept of the art’s age (even today, most rock art remains undated) since archaeology had not yet become an established discipline and there was as yet no idea of the antiquity of humankind or of the very concept of prehistory.

It seems that it was the Chinese who were the pioneers, since the earliest known written reports of rock art are to be found in Han Fei Zi, a book written 2,300 years ago by the philosopher Han Fei (280–233 b.c.). In the fifth century a.d., Li Daoyuan, a geographer of the northern Wei dynasty (a.d. 386–534), wrote a famous geography book called Shui jing zhu (Notes on the Systems of Rivers), which consists mostly of his personal experiences and describes places he had seen. He mentions a score of places with rock art in about half of china’s provinces and states that he had also heard of rock art in India and Pakistan. The book also describes techniques (painting and engraving) and subjects (tigers, horses, goats, and chickens as well as divinities and masks, footprints, and hoofprints).

The earliest known reference to rock art in Europe occurred 1,000 years after Li Daoyuan’s book when, in 1458, Calixtus III, one of the Borgia popes from Valencia, forbade the Spanish to carry out cult ceremonies in a cave with horse pictures—presumably a decorated cave of Ice Age date—showing the persistence of beliefs