Phylogeography and genetic ancestry of tigers (Panthera tigris).
Eight traditional subspecies of tiger (Panthera tigris),of which three recently became extinct, are commonly recognized on the basis of geographic isolation and morphological characteristics. To investigate the species' evolutionary history and to establish objective methods for subspecies recognition, voucher specimens of blood, skin, hair, and/or skin biopsies from 134 tigers with verified geographic origins or heritage across the whole distribution range were examined for three molecular markers: (1) 4.0 kb of mitochondrial DNA (mtDNA) sequence; (2) allele variation in the nuclear major histocompatibility complex class II DRB gene; and (3) composite nuclear microsatellite genotypes based on 30 loci. Relatively low genetic variation with mtDNA,DRB,and microsatellite loci was found, but significant population subdivision was nonetheless apparent among five living subspecies. In addition, a distinct partition of the Indochinese subspecies P. t. corbetti in to northern Indochinese and Malayan Peninsula populations was discovered. Population genetic structure would suggest recognition of six taxonomic units or subspecies: (1) Amur tiger P. t. altaica; (2) northern Indochinese tiger P. t. corbetti; (3) South China tiger P. t. amoyensis; (4) Malayan tiger P. t. jacksoni, named for the tiger conservationist Peter Jackson; (5) Sumatran tiger P. t. sumatrae; and (6) Bengal tiger P. t. tigris. The proposed South China tiger lineage is tentative due to limited sampling. The age of the most recent common ancestor for tiger mtDNA was estimated to be 72,000-108,000 y, relatively younger than some other Panthera species. A combination of population expansions, reduced gene flow, and genetic drift following the last genetic diminution, and the recent anthropogenic range contraction, have led to the distinct genetic partitions. These results provide an explicit basis for subspecies recognition and will lead to the improved management and conservation of these recently isolated but distinct geographic populations of tigers.
Luo
Shu-Jin
SJ
Laboratory of Genomic Diversity, National Cancer Institute, Frederick, Maryland, USA.
Kim
Jae-Heup
JH
Johnson
Warren E
WE
van der Walt
Joelle
J
Martenson
Janice
J
Yuhki
Naoya
N
Miquelle
Dale G
DG
Uphyrkina
Olga
O
Goodrich
John M
JM
Quigley
Howard B
HB
Tilson
Ronald
R
Brady
Gerald
G
Martelli
Paolo
P
Subramaniam
Vellayan
V
McDougal
Charles
C
Hean
Sun
S
Huang
Shi-Qiang
SQ
Pan
Wenshi
W
Karanth
Ullas K
UK
Sunquist
Melvin
M
Smith
James L D
JL
O'Brien
Stephen J
SJ
D000483:Alleles; D000818:Animals; D001499:Bayes Theorem; D005075:Biological Evolution; D016000:Cluster Analysis; D003247:Conservation of Natural Resources; D017931:DNA Primers / Q000737:chemistry; D004272:DNA, Mitochondrial / Q000378:metabolism; D014644:Genetic Variation; D005838:Genotype; D005843:Geography; D006239:Haplotypes; D008285:Major Histocompatibility Complex / Q000235:genetics; D018895:Microsatellite Repeats; D008954:Models, Biological; D008969:Molecular Sequence Data; D010802:Phylogeny; D011110:Polymorphism, Genetic; D046010:Tigers / Q000235:genetics*; D013997:Time Factors
D017931:DNA Primers; D004272:DNA, Mitochondrial