Shallow population histories in deep evolutionary lineages of marine fishes: insights from sardines and anchovies and lessons for conservation

The ghost of introduction past: Spatial and temporal variability in the genetic diversity of invasive smallmouth bass

“…The authors observed a significant decrease in Na for the contemporary population when compared to samples collected 60 years before, likely due to a recent genetic bottleneck. Our results support this proposition, as the CN population exhibited high haplotype, but low nucleotide genetic diversity, as well as significantly negative Tajima's D and Fu's Fs levels, all of which are commonly observed in a population that had undergone a genetic bottleneck before experiencing expansion (Grant & Bowen, 1998). Moreover, the lack of population structure in the CN range, as well as low AR and Na, further supports this notion.…”

Molecular phylogeny and phylogeography of free-living Bryozoa (Cupuladriidae) from both sides of the Isthmus of Panama

“…As indicators of population structure and history (Grant and Bowen, 1998;Nei, 1987), we determined indices of haplotype and nucleotide diversity for each haplotype group. Haplotype diversity (h) was calculated manually as h ¼ 1 À Rf 2 i , where f i is the frequency of the ith haplotype.…”

“…Three of the four haplotype groups in the Pacific show star phylogeny structures (Fig. 6), with high haplotype and low nucleotide diversities (Table 4), indicative of populations that have expanded after a period of low effective population size (Grant and Bowen, 1998). Low F ST values indicate considerable gene flow among these populations.…”

“…Both haplotype and nucleotide diversities of these are low (Table 4), attributable to relatively recent colonization events or periodic regionwide bottlenecks; examination of metapopulation structure is necessary to distinguish between these alternatives. Three Caribbean species show deeper population structure, with high haplotype and nucleotide diversities (Table 4), indicative of larger, more stable populations over evolutionary time (Cupuladria 6 and Discoporella 8) or secondary contact between allopatrically divergent lineages (Cupuladria 4) (Grant and Bowen, 1998). For these species, F ST statistics (Table 5) indicate limited gene flow between populations at Bocas del Toro/Gulf of Mosquitos and those at Costa Arriba/ San Blas.…”

Genetic Diversity and Evolution of Marine Animals Isolated in Marine Lakes

“…Therefore, marine organisms often show low levels of genetic differentiation even over large geographical ranges (Grant and Bowen, 1998), because ocean currents and/or the apparent lack of physical barriers to movement appear to facilitate extensive gene flow (Avise, 2000;Palumbi, 1994).…”