Marked population structure and recent migration in the critically endangered Sumatran orangutan (Pongo abelii).
A multitude of factors influence how natural populations are genetically structured, including dispersal barriers, inhomogeneous habitats, and social organization. Such population subdivision is of special concern in endangered species, as it may lead to reduced adaptive potential and inbreeding in local subpopulations, thus increasing the risk of future extinctions. With only 6600 animals left in the wild, Sumatran orangutans (Pongo abelii) are among the most endangered, but also most enigmatic, great ape species. In order to infer the fine-scale population structure and connectivity of Sumatran orangutans, we analyzed the most comprehensive set of samples to date, including mitochondrial hyper-variable region I haplotypes for 123 individuals and genotypes of 27 autosomal microsatellite markers for 109 individuals. For both mitochondrial and autosomal markers, we found a pronounced population structure, caused by major rivers, mountain ridges, and the Toba caldera. We found that genetic diversity and corresponding long-term effective population size estimates vary strongly among sampling regions for mitochondrial DNA, but show remarkable similarity for autosomal markers, hinting at male-driven long-distance gene flow. In support of this, we identified several individuals that were most likely sired by males originating from other genetic clusters. Our results highlight the effect of natural barriers in shaping the genetic structure of great ape populations, but also point toward important dispersal corridors on northern Sumatra that allow for genetic exchange.
Anthropological Institute & Museum, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland. a.nater@aim.uzh.ch
Alexander
A
Nater
Natasha
N
Arora
Maja P
MP
Greminger
Carel P
CP
van Schaik
Ian
I
Singleton
Serge A
SA
Wich
Gabriella
G
Fredriksson
Dyah
D
Perwitasari-Farajallah
Joko
J
Pamungkas
Michael
M
Krützen
D025041:Animal Migration; D000818:Animals; D001483:Base Sequence; D004272:DNA, Mitochondrial / Q000235:genetics; D056727:Endangered Species; D005243:Feces / Q000737:chemistry; D051456:Gene Flow / Q000235:genetics*; D014644:Genetic Variation; D005828:Genetics, Population; D005843:Geography; D006197:Hair / Q000737:chemistry; D006239:Haplotypes / Q000235:genetics; D007214:Indonesia; D018895:Microsatellite Repeats / Q000235:genetics; D008969:Molecular Sequence Data; D012150:Polymorphism, Restriction Fragment Length; D057080:Pongo abelii / Q000235:genetics / Q000502:physiology*; D011156:Population Density; D011157:Population Dynamics; D060888:Real-Time Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
D004272:DNA, Mitochondrial