Species with large effective population sizes
can have high intraspecific genetic diversity, which could
overlap with interspecific divergence. DNA barcoding will
be ambiguous in these situations. Imperfect taxonomy also
could lead to erroneous identifications (Meyer and Paulay
2005). Because different organisms have different population
histories, the success of DNA barcoding will vary accordingly.
Even within the same group of organisms (e.g.,
butterflies), the performance of DNA barcoding can vary
among geographic regions and ecosystems (Elias et al.
2007).