Abstract: In this review , we discuss two applications of mtDNA analysis in zoological conservation biology. One is to describe and manage genetic diversity , an issue more relevant to long2term planning for conservation. Another is its use as a tool for the short-term demographic management of populations. We emphasize its use in recognizing Evolutionary Significant Units ( ESUs) and Management Units (MUs) . ESUs are recognized to partition genetic diversity and assess conservation value and can be identified as populations having significant phylogenetic divergence of mtDNA from other populations , with corroborating divergence of allele frequencies at nuclear loci. MUs are defined as demographically independent breeding units and are identified as populations having distinctive allele frequencies , regardless of phylogenetic structure and the level of genetic divergence. ESUs and MUs are both important units in conservation biology. The use of mtDNA should be in concert with analysis of nuclear loci in order to obtain reliable data for conservation.

Key words: cavefishes, concept, species diversity, research progress