To better understand the relationship between changing retouched implement morphology and intensity of reduction, archaeologists must develop measures of morphological change that work outside of, and challenge, existing typologies. This paper attempts such an approach by exploring changes in four aspects of implement morphology as retouch increases, using a population of scrapers - or non-formally retouched flakes - from four rockshelters in northern Australia. The results allow the formulation of a reduction model that accounts for many of the differences in implement morphology that underlie most traditional scraper typologies. The results provide the basis for a critique of an early but influential scraper typology that underlies most Australian classifications in use today
