Gomez, A., G. J. Adcock, D. H. Lunt, and G. R. Carvalho (2002) The interplay between colonization history and gene flow in passively dispersing zooplankton: microsatellite analysis of rotifer resting egg banks. JOURNAL OF EVOLUTIONARY BIOLOGY 15:158-171. PDF
Zooplanktonic organisms that disperse passively as diapausing eggs often exhibit surprisingly strong population subdivision given their high colonization ability. Here we attempt to disentangle the impacts of colonization history and gene flow on these organisms by studying the population genetic structure of the rotifer Brachionus plicatilis. The resting egg banks of B. plicatilis in four-teen salt take populations in the Iberian Peninsula were examined using seven microsatellite loci. A remarkably high degree of geographical structuring was found (Fst = 0.43), with a significant pattern of isolation by distance. Microsatellite loci were in genetic equilibrium, ruling out inbreeding as an important force in population structuring. Comparisons are drawn with previously published phylogeographical data. Surprisingly, introgression of nuclear genes was detected in neighbouring populations with divergent mtDNA haplotypes. These results stress the long lasting impact of colonization history and the modulating effect of gene flow at local scales in these organisms.
The interplay between colonization history and gene flow in passively dispersing zooplankton: microsatellite analysis of rotifer resting egg banks
An efficient method for PCR-based isolation of microsatellite arrays (PIMA)
Lunt, D. H., W. F. Hutchinson, and G. R. Carvalho (1999) An efficient method for PCR-based isolation of microsatellite arrays (PIMA). MOLECULAR ECOLOGY 8:891-893. PDF
Laboratory PIMA protocol
Microsatellite markers for the hake Macruronus magellanicus amplify other gadoid fish
D’Amato, M. E., D. H. Lunt, and G. R. Carvalho (1999) Microsatellite markers for the hake Macruronus magellanicus amplify other gadoid fish MOLECULAR ECOLOGY 8:1086-1088. PDF
The long-tail hake Macruronus magellanicus is a demersal pelagic species that constitutes the most abundant fish resource in the southwestern Atlantic (Prenski et al. 1996). However, the fisheries have only recently developed and stock identification is required before large-scale exploita- tion occurs. However, ecological (R. Gonzalez, B. Prenski, personal communication) and morphological (A. Giussi,personal communication) data suggest stock differentiation in Patagonian gulfs. Mitochondrial DNA (mtDNA) restriction fragment length polymorphism (RFLP), the only genetic data available, detected no differentiation among coastal and off- shore samples (M. E. D’Amato & G. R. Carvalho, unpublished), indicating a need to develop more polymorphic markers such as microsatellites.
