... Carbon isotopes in photosynthesis.BioScience 38:328–336.Ostrom, P. H., C. G. Manuel, and S. H. Gage. 1997. Estab-lishing pathways of energy flow for insect predators using stable isotope ratios: ... mass spectrometrywere performed in the Princeton Isotope GeochemistryLaboratory (Princeton, New Jersey, USA; 1996 sam-ples) and the Harvard Laboratory for GeochemicalOceanography (Cambridge, ... as␦13C0. The similarity of this value to larval host plant(Table 1) indicates that there is little net carbon isotopefractionation (a shift in isotope ratio due to isotopediscrimination) associated...