POPULATION-GENETICS AND SYSTEMATICS OF ASIAN ELEPHANT (ELEPHAS-MAXIMUS) - A STUDY BASED ON SEQUENCE VARIATION AT THE CYT-B GENE OF PCR-AMPLIFIED MITOCHONDRIAL-DNA FROM HAIR BULBS

To investigate genetic variability and differentiation in Asian elepha nt (Elephas maximus) a total of 53 individuals from Sri Lanka, souther n India, northeastern India, northern and southern Myanmar (Burma), no rthern and eastern Thailand, and Vietnam were screened for sequence va riation at the mitochondrial cytochrome b gene. An about 480 bp part o f the gene was PCR amplified from hair bulbs, directly cycle-sequenced , and 335 bp were analysed on a direct blot sequencing device. Eight h aplotypes, differing from one another by one to six third position tra nsitions at a total of seven polymorphic sites, were found. They diffe red from published sequences of African elephant (Loxodonta africana) by at least 18, and from those of the Siberian woolly mammoth (Mammuth us primigenius) by at least eight nucleotide substitutions. Haplotypes separated out by nucleotide divergence into two major groups, which s howed differences in their geographic distribution. However, there was no indication of a major separation between elephants from Sri Lanka and the Asian mainland, previously assumed to represent two different subspecies. Populations studied showed remarkable differences as to es timates of haplotype and nucleotide diversity Phylogeographic patterns of haplotypes suggest that Asian elephants have formed a coherent pop ulation after their Pliocene invasion of southern and southeastern Asi a. Taking into account records on population histories, the present lo cal differentiation can be explained by varying human impact on popula tion structure and size.