title: Comparison of population genetic patterns in two widespread freshwater mussels with contrasting life histories in western North America.
abstract: We investigate population genetic structuring in Margaritifera falcata, a freshwater mussel native to western North America, across the majority of its geographical range. We find shallow rangewide genetic structure, strong population-level structuring and very low population diversity in this species, using both mitochondrial sequence and nuclear microsatellite data. We contrast these patterns with previous findings in another freshwater mussel species group (Anodonta californiensis/A. nuttalliana) occupying the same continental region and many of the same watersheds. We conclude that differences are likely caused by contrasting life history attributes between genera, particularly host fish requirements and hermaphroditism. Further, we demonstrate the occurrence of a 'hotspot' for genetic diversity in both groups of mussels, occurring in the vicinity of the lower Columbia River drainage. We suggest that stream hierarchy may be responsible for this pattern and may produce similar patterns in other widespread freshwater species.
authors.affiliation: Ecology Center and Department of Wildland Resources, Utah State University, Logan, UT, 84322, USA.
authors.forename: K E
authors.initials: KE
authors.lastname: Mock
authors.forename: J C
authors.initials: JC
authors.lastname: Brim Box
authors.forename: J P
authors.initials: JP
authors.lastname: Chong
authors.forename: J
authors.initials: J
authors.lastname: Furnish
authors.forename: J K
authors.initials: JK
authors.lastname: Howard
mesh_terms: D000818:Animals; D049877:Anodonta / Q000145:classification / Q000235:genetics* / Q000502:physiology; D002467:Cell Nucleus / Q000235:genetics; D004272:DNA, Mitochondrial / Q000235:genetics; D005399:Fishes; D005618:Fresh Water; D014644:Genetic Variation; D005828:Genetics, Population / Q000379:methods*; D006239:Haplotypes; D008018:Life Cycle Stages; D018895:Microsatellite Repeats; D008969:Molecular Sequence Data; D009656:North America; D012098:Reproduction / Q000502:physiology; D017422:Sequence Analysis, DNA; D049876:Unionidae / Q000145:classification / Q000235:genetics* / Q000502:physiology
chemical_list: D004272:DNA, Mitochondrial
keywords: Anodonta; Columbia River Basin; Margaritifera falcata; genetic diversity; genetic structure; hermaphroditism; inbreeding