Modern Wyoming plant and pronghorn isoscapes and their implications for archaeology

Stable isotope ratios obtained from pronghorn teeth recovered from archaeological sites in southwestern Wyoming may provide information on past climate and hunter behavior. However, the interpretation of archaeological isotope values depends on pronghorn isotopic correlations with the environment and geography. To investigate these correlations, a series of modern Wyoming carbon, oxygen and strontium isoscapes are compared with recent temperature, humidity and geological variation. Results indicate that both pronghorn and sagebrush carbon, and to a lesser degree oxygen, isotope ratios are tied to relative humidity. Temperature is correlated with oxygen isotope ratios in sagebrush, but not pronghorn. Strontium isotope ratios in both sagebrush and pronghorn vary with geography, which in turn reflects variation in geology.