Archer, Steve. 1982. Dietary Analysis of Sympatric Herbivores at Wind Cave National Park. 1 p. + 7 tables.
Plants fractionate the naturally occurring isotopes of carbon during the process of photosynthesis. This fractionation results in distinct groups of plants which can be characterized by their different ratios of Carbon 13 to Carbon 12 (delta Carbon 13 values). These plants generally compose two broad categories referred to as C3 and C4 plants. These specimens thus possess a unique label which cannot only be used to determine their photosynthetic pathway, but also as a tracer to identiry this carbon as it passes through the system. Five species tested include bison, pronghorn, prairie dog, elk, and mule deer.