title: High genetic diversity in a remote island population system: sans sex.
abstract: It has been proposed that long-distance dispersal of mosses to the Hawaiian Islands rarely occurs and that the Hawaiian population of the allopolyploid peat moss Sphagnum palustre probably resulted from a single dispersal event. Here, we used microsatellites to investigate whether the Hawaiian population of the dioicous S. palustre had a single founder and to compare its genetic diversity to that found in populations of S. palustre in other regions. The genetic diversity of the Hawaiian population is comparable to that of larger population systems. Several lines of evidence, including a lack of sporophytes and an apparently restricted natural distribution, suggest that sexual reproduction is absent in the Hawaiian plants. In addition, all samples of Hawaiian S. palustre share a genetic trait rare in other populations. Time to most recent ancestor (TMRCA) analysis indicates that the Hawaiian population was probably founded 49-51 kyr ago. It appears that all Hawaiian plants of S. palustre descend from a single founder via vegetative propagation. The long-term viability of this clonal population coupled with the development of significant genetic diversity suggests that vegetative propagation in a moss does not necessarily preclude evolutionary success in the long term.
authors.affiliation: Environmental Science Program, Ramapo College, Mahwah, NJ 07430, USA.
authors.forename: Eric F
authors.initials: EF
authors.lastname: Karlin
authors.affiliation: Department of Botany, University of Wisconsin-Madison, Madison, WI 53706, USA.
authors.forename: Sara C
authors.initials: SC
authors.lastname: Hotchkiss
authors.affiliation: Department of Biology, Duke University, Durham, NC 27708, USA.
authors.forename: Sandra B
authors.initials: SB
authors.lastname: Boles
authors.affiliation: Systematics and Evolution Group, Section of Natural History, Museum of Natural History and Archaeology, Norwegian University of Science and Technology, N-7491 Trondheim, Norway.
authors.forename: Hans K
authors.initials: HK
authors.lastname: Stenøien
authors.affiliation: Systematics and Evolution Group, Section of Natural History, Museum of Natural History and Archaeology, Norwegian University of Science and Technology, N-7491 Trondheim, Norway.
authors.forename: Kristian
authors.initials: K
authors.lastname: Hassel
authors.affiliation: Systematics and Evolution Group, Section of Natural History, Museum of Natural History and Archaeology, Norwegian University of Science and Technology, N-7491 Trondheim, Norway.
authors.forename: Kjell I
authors.initials: KI
authors.lastname: Flatberg
authors.affiliation: Department of Biology, Duke University, Durham, NC 27708, USA.
authors.forename: A Jonathan
authors.initials: AJ
authors.lastname: Shaw
mesh_terms: D018703:Founder Effect; D014644:Genetic Variation; D005843:Geography; D006239:Haplotypes; D006254:Hawaii; D018895:Microsatellite Repeats; D012100:Reproduction, Asexual; D044003:Sphagnopsida / Q000235:genetics* / Q000502:physiology