title: Genetic and acoustic population structuring in the Okinawa least horseshoe bat: are intercolony acoustic differences maintained by vertical maternal transmission?
abstract: The origin and meaning of echolocation call frequency variation within rhinolophid bats is not well understood despite an increasing number of allopatric and sympatric examples being documented. A bimodal distribution of mean regional call frequency within the Okinawa-jima Island population of Rhinolophus cornutus pumilus (Rhinolophidae) provided a unique opportunity to investigate geographic call frequency variation early in its development. Individual resting echolocation frequencies, partial mitochondrial DNA D-loop sequences and genotypes from six microsatellite loci were obtained from 288 individuals in 11 colonies across the entire length of the island, and nearby Kume-jima Island. Acoustic differences (5-8 kHz) observed between the north and south regions have been maintained despite evidence of sufficient nuclear gene flow across the middle of the island. Significant subdivision of maternally inherited D-loop haplotypes suggested a limitation of movement of females between regions, but not within the regions, and was evidence of female philopatry. These results support a 'maternal transmission' hypothesis whereby the difference in the constant frequency (CF) component between the regions is maintained by mother-offspring transmission of CF, the restricted dispersal of females between regions and small effective population size. We suggest that the mean 5-8 kHz call frequency difference between the regions might develop through random cultural drift.
authors.affiliation: Department of Ecology and Evolutionary Biology, Graduate School of Life Sciences, Tohoku University, Aoba, Sendai, Miyagi 980-8578, Japan. hajimeyoshino@mail.tains.tohoku.ac.jp
authors.forename: Hajime
authors.initials: H
authors.lastname: Yoshino
authors.forename: Kyle N
authors.initials: KN
authors.lastname: Armstrong
authors.forename: Masako
authors.initials: M
authors.lastname: Izawa
authors.forename: Jun
authors.initials: J
authors.lastname: Yokoyama
authors.forename: Masakado
authors.initials: M
authors.lastname: Kawata
mesh_terms: D000818:Animals; D002685:Chiroptera / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000235:genetics; D004455:Echolocation; D005260:Female; D051456:Gene Flow; D014644:Genetic Variation; D005828:Genetics, Population; D005838:Genotype; D040582:Inheritance Patterns; D007564:Japan; D018895:Microsatellite Repeats; D017422:Sequence Analysis, DNA
chemical_list: D004272:DNA, Mitochondrial