Pictogram of a quadruped, suggested to depict a tiger, at Raisen, India
ESTIMATING THE AGE OF ROCK ART DIRECTLY
'Direct dating' of rock art is contingent upon two prerequisites: first, the physical relationship of the art and the dating criterion must be direct and indisputable; second, the propositions made concerning the chronological relationship of the rock art and the dating criterion should be scientifically testable (i.e. they should be refutable). The first requirement is met if the phenomenon being dated is directly relatable to the rock art: either of the same age (e.g. a paint binder, or the fracture surfaces caused by the impact used to make a petroglyph), older than the art (e.g. its support surface, or a lichen thallus dissected by an engraved line), or younger than the art (e.g. a subsequent mineral deposit, or a fracture transecting the motif) (Bednarik 1981, 1996).
The second requirement of direct dating demands that the chronological data obtained for the dating criterion (e.g. the paint binder, the support surface, the mineral deposit) and its relationship with the actual age of the rock art must be testable by refutation. For instance, some archaeologists have included the subjects supposedly depicted in the art as a form of direct dating. This is unacceptable as direct dating, as explained under 'Iconography', because the iconographic 'identifications' of archaeologists are not testable, they depend upon an untestable relationship between a form perceived by a subjective organism (the rock art 'interpreter') and the iconography of an alien culture. Archaeologists may well believe that they are able to identify depicted objects, and perhaps they are right occasionally, but science does not proceed by accepting such propositions as evidence - except when studying the perception of the scholar in question.
The criteria of direct rock art dating are clear, precise and rigorous. Direct dating does not produce actual ages of rock art, it generates testable propositions about the relevance of specific physical or chemical data to the true age of rock art. The interpretation of the relation demands a considerable understanding of the dating technique used; of the circumstances of sample collection, processing and distorting factors; and of the limitations and quite specific qualifications applying to the stated results. None of the methods used in direct dating of rock art produces results that can be conveyed by some simple numerical expression, which unfortunately is how they are often quoted in the archaeological literature. Therefore it is fair to say that archaeologically published results of direct dating are often presented in a misleading form. Such results should always be understood within the context they were acquired and within which the archaeometrists expect them to be seen (Bednarik 1996, 2000a; Watchman 1999).
Consider, for instance, the ubiquitous radiocarbon analysis results, and the way they are misused (see Pitfalls in rock art dating). There are very few kinds of circumstances in which a carbon-14 result can directly be related to the age of rock art, and so far (in 2001) no rock art has been dated by radiocarbon. This is not what one would be led to believe if one sifted through recent archaeological commentaries.
On the following pages aspects of these 'direct dating' approaches are divided into eight headings: