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Kingdom Chromista and its eight phyla: a new synthesis emphasising periplastid protein targeting, cytoskeletal and periplastid evolution, and ancient divergences

In 1981 I established kingdom Chromista, distinguished from Plantae because of its more complex chloroplast-associated membrane topology and rigid tubular multipartite ciliary hairs. Plantae originated by converting a cyanobacterium to chloroplasts with Toc/Tic translocons; most evolved cell walls early, thereby losing phagotrophy. Chromists originated by enslaving a phagocytosed ...

Kingdoms Protozoa and Chromista and the eozoan root of the eukaryotic tree

Thomas Cavalier-Smith * 0 0 Thomas Cavalier-Smith Articles on similar topics can be found in the following collections: evolution (794 articles) taxonomy and systematics (81 articles) Receive free

A Higher Level Classification of All Living Organisms

We present a consensus classification of life to embrace the more than 1.6 million species already provided by more than 3,000 taxonomists’ expert opinions in a unified and coherent, hierarchically ranked system known as the Catalogue of Life (CoL). The intent of this collaborative effort is to provide a hierarchical classification serving not only the needs of the CoL’s database ...

Origin of the cell nucleus, mitosis and sex: roles of intracellular coevolution

Background The transition from prokaryotes to eukaryotes was the most radical change in cell organisation since life began, with the largest ever burst of gene duplication and novelty. According to the coevolutionary theory of eukaryote origins, the fundamental innovations were the concerted origins of the endomembrane system and cytoskeleton, subsequently recruited to form the ...

Deep phylogeny, ancestral groups and the four ages of life

life Thomas Cavalier-Smith* Organismal phylogeny depends on cell division, stasis, mutational divergence, cell mergers (by sex or symbiogenesis), lateral gene transfer and death. The tree of life is a

Two-Gene Phylogeny of Bright-Spored Myxomycetes (Slime Moulds, Superorder Lucisporidia)

Myxomycetes, or plasmodial slime-moulds, are one of the largest groups in phylum Amoebozoa. Nonetheless, only ∼10% are in the database for the small subunit (SSU) ribosomal RNA gene, the most widely used gene for phylogenetics and barcoding. Most sequences belong to dark-spored Myxomycetes (order Fuscisporida); the 318 species of superorder Lucisporidia (bright-spored) are ...

Origin of mitochondria by intracellular enslavement of a photosynthetic purple bacterium

Thomas Cavalier-Smith * 0 0 Department of Zoology, University of Oxford , South Parks Road, Oxford OX1 3PS , UK Mitochondria originated by permanent enslavement of purple non-sulphur bacteria. These

Rooting the tree of life by transition analyses

Background Despite great advances in clarifying the family tree of life, it is still not agreed where its root is or what properties the most ancient cells possessed – the most difficult problems in phylogeny. Protein paralogue trees can theoretically place the root, but are contradictory because of tree-reconstruction artefacts or poor resolution; ribosome-related and DNA-handling ...

Cell evolution and Earth history: stasis and revolution

Thomas Cavalier-Smith * 0 0 Department of Zoology, University of Oxford , South Parks Road, Oxford OX1 3PS , UK This synthesis has three main parts. The first discusses the overall tree of life and

18S rDNA Phylogeny of Lamproderma and Allied Genera (Stemonitales, Myxomycetes, Amoebozoa)

The phylogenetic position of the slime-mould genus Lamproderma (Myxomycetes, Amoebozoa) challenges traditional taxonomy: although it displays the typical characters of the order Stemonitales, it appears to be sister to Physarales. This study provides a small subunit (18S or SSU) ribosomal RNA gene-based phylogeny of Lamproderma and its allies, with new sequences from 49 specimens ...

DNA evidence for global dispersal and probable endemicity of protozoa

Background It is much debated whether microbes are easily dispersed globally or whether they, like many macro-organisms, have historical biogeographies. The ubiquitous dispersal hypothesis states that microbes are so numerous and so easily dispersed worldwide that all should be globally distributed and found wherever growing conditions suit them. This has been broadly upheld for ...

Multigene Phylogeny of Choanozoa and the Origin of Animals

Animals are evolutionarily related to fungi and to the predominantly unicellular protozoan phylum Choanozoa, together known as opisthokonts. To establish the sequence of events when animals evolved from unicellular ancestors, and understand those key evolutionary transitions, we need to establish which choanozoans are most closely related to animals and also the evolutionary ...

Evolutionary position of breviate amoebae and the primary eukaryote divergence

Integration of ultrastructural and molecular sequence data has revealed six supergroups of eukaryote organisms (excavates, Rhizaria, chromalveolates, Plantae, Amoebozoa and opisthokonts), and the root of the eukaryote evolutionary tree is suggested to lie between unikonts (Amoebozoa, opisthokonts) and bikonts (the other supergroups). However, some smaller lineages remain of ...

Evolution of Dinoflagellate Unigenic Minicircles and the Partially Concerted Divergence of Their Putative Replicon Origins

Dinoflagellate chloroplast genes are unique in that each gene is on a separate minicircular chromosome. To understand the origin and evolution of this exceptional genomic organization we completely sequenced chloroplast psbA and 23S rRNA gene minicircles from four dinoflagellates: three closely related Heterocapsa species (H. pygmaea, H. rotundata, and H. niei) and the very ...

Large-Scale Phylogenomic Analyses Reveal That Two Enigmatic Protist Lineages, Telonemia and Centroheliozoa, Are Related to Photosynthetic Chromalveolates

Fabien Burki 1 Yuji Inagaki Jon Brate John M. Archibald 3 Patrick J. Keeling k Thomas Cavalier-Smith 2 Miako Sakaguchi Tetsuo Hashimoto Ales Horak k Surendra Kumar Dag Klaveness Kjetill S. Jakobsen 0

Analyses of RNA Polymerase II Genes from Free-Living Protists: Phylogeny, Long Branch Attraction, and the Eukaryotic Big Bang

The phylogenetic relationships among major eukaryotic protist lineages are largely uncertain. Two significant obstacles in reconstructing eukaryotic phylogeny are long-branch attraction (LBA) effects and poor taxon sampling of free-living protists. We have obtained and analyzed gene sequences encoding the largest subunit of RNA Polymerase II (RPB1) from Naegleria gruberi (a ...