In corresponding to ESU (Evolutionaryly Significant Unit), an OTU (Operational Taxonomic Unit) measured by DNA variation may be used to replace categories of taxa since its subjectivity.

• 为了避免物种和其他分类群的随意性, 建议以DNA 序列变异作为可操作的分类单元(OTU)和国际上进化上显著单元(ESU)相呼应。