This statement is the cornerstone for the development of a methodology based on the analysis of stable isotopes and directed to respond to questions as diverse as the structure and function of biological communities, migration patterns of species or populations or the study of the impact of global change on vector ecosystems.
What's a stable isotope?
Stable isotopes are non-radioactive atoms of a particular chemical element which have the same number of protons but different number of neutrons. The relative abundance of the heavy compared with the light isotope (e.g. 13C/12C) is given the name isotopic signature or fingerprint and is represented by a delta symbol (?) by means of the ratio of this proportion in the sample, with respect to international standards, giving the results in units per thousand (‰).