title: Controls on diatom biogeography in the ocean.
abstract: The extent to which the spatial distribution of marine planktonic microbes is controlled by local environmental selection or dispersal is poorly understood. Our ability to separate the effects of these two biogeographic controls is limited by the enormous environmental variability both in space and through time. To circumvent this limitation, we analyzed fossil diatom assemblages over the past ~1.5 million years from the world oceans and show that these eukaryotic microbes are not limited by dispersal. The lack of dispersal limitation in marine diatoms suggests that the biodiversity at the microbial level fundamentally differs from that of macroscopic animals and plants for which geographic isolation is a common component of speciation.
authors.affiliation: Environmental Biophysics and Molecular Ecology Program, Institute of Marine and Coastal Sciences, Rutgers University, 71 Dudley Road, New Brunswick, NJ 08901, USA. pedro@uvigo.es
authors.forename: Pedro
authors.initials: P
authors.lastname: Cermeño
authors.forename: Paul G
authors.initials: PG
authors.lastname: Falkowski
mesh_terms: D044822:Biodiversity; D005075:Biological Evolution; D055907:Climatic Processes; D016208:Databases, Factual; D017377:Diatoms / Q000145:classification / Q000235:genetics / Q000502:physiology; D017753:Ecosystem; D005580:Fossils; D049810:Genetic Speciation; D005843:Geography; D019015:Geologic Sediments / Q000382:microbiology*; D009792:Oceans and Seas; D010839:Phytoplankton / Q000145:classification / Q000235:genetics / Q000502:physiology; D012623:Seawater / Q000382:microbiology*