A planktonic diatom displays genetic structure over small spatial scales

A1 Journal article (refereed)

Internal Authors/Editors

Publication Details

List of Authors: Josefin Sefbom, Anke Kremp, Karin Rengefors, Per R. Jonsson, Conny Sjöqvist, Anna Godhe
Publisher: Wiley
Publication year: 2018
Journal: Environmental Microbiology
Volume number: 20
Issue number: 8


Marine planktonic microalgae have potentially global dispersal, yet
reduced gene flow has been confirmed repeatedly for several species.
Over larger distances (>200 km) geographic isolation and restricted
oceanographic connectivity have been recognized as instrumental in
driving population divergence. Here we investigated whether similar
patterns, that is, structured populations governed by geographic
isolation and/or oceanographic connectivity, can be observed at smaller
(6–152 km) geographic scales. To test this we established 425 clonal
cultures of the planktonic diatom Skeletonema marinoi collected
from 11 locations in the Archipelago Sea (northern Baltic Sea). The
region is characterized by a complex topography, entailing several
mixing regions of which four were included in the sampling area. Using
eight microsatellite markers and conventional F‐statistics,
significant genetic differentiation was observed between several sites.
Moreover, Bayesian cluster analysis revealed the co‐occurrence of two
genetic groups spread throughout the area. However, geographic isolation
and oceanographic connectivity could not explain the genetic patterns
observed. Our data reveal hierarchical genetic structuring whereby
despite high dispersal potential, significantly diverged populations
have developed over small spatial scales. Our results suggest that
biological characteristics and historical events may be more important
in generating barriers to gene flow than physical barriers at small
spatial scales.

Last updated on 2020-12-08 at 06:20