Within a given habitat, herbivores generally have a higher strontium/calcium ratio in their bone mineral than do carnivores; this observation makes it possible to estimate the proportion of meat and vegetable foods in the diet of humans who have left excavated remains. The analysis is by atomic absorption spectrophotometry, and the Natufian Cave of Ha Yonim, flanking the Galilee, is being used as a test site. -- AATA