Tomas Cedhagen

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Shallow marine benthic communities around Antarctica show high levels of endemism, gigantism, slow growth, longevity and late maturity, as well as adaptive radiations that have generated considerable biodiversity in some taxa. The deeper parts of the Southern Ocean exhibit some unique environmental features, including a very deep continental shelf and a(More)
Benthic foraminifers inhabit a wide range of aquatic environments including open marine, brackish, and freshwater environments. Here we show that several different and diverse foraminiferal groups (miliolids, rotaliids, textulariids) and Gromia, another taxon also belonging to Rhizaria, accumulate and respire nitrates through denitrification. The widespread(More)
N that it is widely accepted that global warming is happening, there is a growing demand for accurate forecasts of its effects, and much concern about its effects on biological diversity. Specialists know that theoretical models of these effects are limited—although useful in certain contexts when all the provisions, preconditions, and limitations of a(More)
Benthic foraminifera are unicellular eukaryotes found abundantly in many types of marine sediments. Many species survive and possibly reproduce in anoxic habitats, but sustainable anaerobic metabolism has not been previously described. Here we demonstrate that the foraminifer Globobulimina pseudospinescens accumulates intracellular nitrate stores and that(More)
Despite its often featureless appearance, the deep-ocean floor includes some of the most diverse habitats on Earth. However, the accurate assessment of global deep-sea diversity is impeded by a paucity of data on the geographical ranges of bottom-dwelling species, particularly at the genetic level. Here, we present molecular evidence for exceptionally wide(More)
Fossil Foraminifera appear in the Early Cambrian, at about the same time as the first skeletonized metazoans. However, due to the inadequate preservation of early unilocular (single-chambered) foraminiferal tests and difficulties in their identification, the evolution of early foraminifers is poorly understood. By using molecular data from a wide range of(More)
The measurement of species diversity represents a powerful tool for assessing the impacts of human activities on marine ecosystems. Traditionally, the impact of fish farming on the coastal environment is evaluated by monitoring the dynamics of macrobenthic infaunal populations. However, taxonomic sorting and morphology-based identification of the(More)
Komokiaceans are testate agglutinated protists, extremely diverse and abundant in the deep sea. About 40 species are described and share the same main morphological feature: a test consisting of narrow branching tubules forming a complex system. In some species, the interstices between the tubules are filled by sediment, creating a mudball structure.(More)
We describe two new species of spherical single-chambered ('saccamminid') foraminifera from the bathyal and abyssal Weddell Sea (Southern Ocean), collected in epibenthic sledge and Agassiz trawl samples obtained during the 2005 ANDEEP III campaign. Both are assigned to Leptammina gen. nov. The new genus is similar in overall test morphology to Saccammina(More)
1 Tropical Biosphere Research Center, University of the Ryukyus, Motobu, Okinawa, Japan, 2 Research and Development Center for Submarine Resources, Japan Agency for Marine-Earth Science and Technology, Yokosuka, Japan, 3 Department of Genetics and Evolution, University of Geneva, Geneva, Switzerland, 4 National Oceanography Centre, University of Southampton(More)