Regional Genetic Structuring and Evolutionary History of the Impala Aepyceros melampus

TY - JOUR

T1 - Regional Genetic Structuring and Evolutionary History of the Impala Aepyceros melampus

AU - Lorenzen, Eline Deirdre

AU - Arctander, Peter

AU - Siegismund, Hans Redlef

PY - 2006

Y1 - 2006

N2 - Samples of 162 impala antelope (Aepyceros melampus) from throughout its distribution range in sub-Saharan Africa were surveyed using eight polymorphic microsatellite loci. Furthermore, 155 previously published mitochondrial DNA (mtDNA) sequences from the same localities were reanalyzed. Two subspecies of impala are presently recognized-the isolated black-faced impala (Aepyceros melampus petersi) in southwest Africa and the common impala (Aepyceros melampus melampus) abundant in southern and east Africa. All tests performed indicated significant genetic differentiation at the subspecific level. Furthermore, individual-based analyses split the common impala subspecies into two distinct genetic groups, conforming with regional geographic affiliation to southern or east Africa. This was supported by assignment tests, genetic distance measures, pairwise values, and analysis of molecular variance. We suggest that the presence of such previously unknown regional structuring within the subspecies reflects a pattern of colonization from a formerly large panmictic population in southern Africa toward east Africa. This scenario was supported by a progressive decline in population diversity indices toward east Africa and a significant increase in the quantity /(1 - ). Both microsatellite and mtDNA data indicated a genetic distinctiveness of the Samburu population in Kenya.

AB - Samples of 162 impala antelope (Aepyceros melampus) from throughout its distribution range in sub-Saharan Africa were surveyed using eight polymorphic microsatellite loci. Furthermore, 155 previously published mitochondrial DNA (mtDNA) sequences from the same localities were reanalyzed. Two subspecies of impala are presently recognized-the isolated black-faced impala (Aepyceros melampus petersi) in southwest Africa and the common impala (Aepyceros melampus melampus) abundant in southern and east Africa. All tests performed indicated significant genetic differentiation at the subspecific level. Furthermore, individual-based analyses split the common impala subspecies into two distinct genetic groups, conforming with regional geographic affiliation to southern or east Africa. This was supported by assignment tests, genetic distance measures, pairwise values, and analysis of molecular variance. We suggest that the presence of such previously unknown regional structuring within the subspecies reflects a pattern of colonization from a formerly large panmictic population in southern Africa toward east Africa. This scenario was supported by a progressive decline in population diversity indices toward east Africa and a significant increase in the quantity /(1 - ). Both microsatellite and mtDNA data indicated a genetic distinctiveness of the Samburu population in Kenya.

U2 - 10.1093/jhered/esj012

DO - 10.1093/jhered/esj012

M3 - Journal article

C2 - 16407525

SN - 0022-1503

VL - 97

SP - 119

EP - 132

JO - Journal of Heredity

JF - Journal of Heredity

IS - 2

ER -