To date molecular data have not revealed the exact phylogenetic position of Balanophoraceae in relation to hemiparasitic Santalales. To elucidate the phylogeny of Santalales and the position of Balanophoraceae, three plastid genes (matK, rbcL, accD), three nuclear genes (SSU and LSU rDNA and RPB2) and one mitochondrial gene (matR) from 197 Santalales samples (including 11 Balanophoraceae species) were analyzed with parsimony, maximum likelihood and Bayesian inference methods. Our results demonstrate that Balanophoraceae is composed of two well‐supported clades: a relatively slow‐evolving one including Dactylantus, Hachettea, and Mystropetalon (Mystropetalaceae) and an extremely fast‐evolving one composed of the remaining Balanophoraceae s.str. Support for monophyly of the two clades was low, thus it appears holoparasitism has arisen twice independently in Santalales. These two clades appeared during a time of great change in the order (ca. 100 Ma) when several major evolutionary innovations emerged, e.g., the root hemiparasites of Santalaceae s.l., the first aerial parasites (Misodendraceae), herbaceous root parasites (Schoepfiaceae), root parasitic Loranthaceae (the ancestors of aerial parasitic mistletoes), as well as the holoparasites in Balanophoraceae and Mystropetalaceae.

The reference sequence for each human chromosome provides the framework for understanding genome function, variation and evolution. Here we report the finished sequence and biological annotation of human chromosome 1. Chromosome 1 is gene-dense, with 3,141 genes and 991 pseudogenes, and many coding sequences overlap. Rearrangements and mutations of chromosome 1 are prevalent in cancer and many other diseases. Patterns of sequence variation reveal signals of recent selection in specific genes that may contribute to human fitness, and also in regions where no function is evident. Fine-scale recombination occurs in hotspots of varying intensity along the sequence, and is enriched near genes. These and other studies of human biology and disease encoded within chromosome 1 are made possible with the highly accurate annotated sequence, as part of the completed set of chromosome sequences that comprise the reference human genome.

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Clitellata is a major clade of Annelida comprising nearly all freshwater and terrestrial annelids as well as several marine species. We investigated clitellate phylogenetic relationships using transcriptomes sampled from 74 taxa (64 clitellates and 10 polychaetes), including multiple representatives of nearly all major clitellate higher taxa (Branchiobdellida, Capilloventridae, Crassiclitellata, Enchytraeidae, Haplotaxidae, Hirudinida, Lumbriculida, Moniligastridae, Naididae, Parvidrilidae, Phreodrilidae, Propappidae and Randiellidae). We used a number of filtered data matrices and phylogenetic analyses to examine the effects of data partitioning, missing data and compositional and branch‐length heterogeneity and used the resulting phylogenies for divergence time estimation and ancestral habitat reconstructions. All analyses and filtering methods produced a consistent, strongly supported topology in which (a) Enchytraeidae, Hirudinida, Hirudinea (here, Branchiobdellida plus Hirudinida), Lumbriculida, Lumbriculata (Lumbriculida plus Hirudinea), Phreodrilidae and Naididae are monophyletic, (b) a Parvidrilidae + Randiellidae clade is sister to the rest of Clitellata, (c) Phreodrilidae is sister to Naididae, (d) Haplotaxidae is non‐monophyletic, with some haplotaxids grouping with Crassiclitellata + Moniligastridae, (e) the Phreodrilidae + Naididae clade is sister to all other clitellates except Parvidrilidae + Randiellidae and Capilloventridae, and (f) Lumbriculata is sister to the Crassiclitellata + Moniligastridae + Haplotaxidae (in part) clade. Ancestral habitat reconstructions and divergence time analysis suggested that the most recent common ancestor of Clitellata lived in freshwater during the Devonian (419–359 million years ago) and that all major extant clitellate lineages arose over the next ~150 million years, with multiple lineages subsequently returning to marine habitats or invading land. This study provides a phylogenetic framework for further investigation of the geological, environmental and biotic forces and genomic changes that may have impacted clitellate evolution and enabled several major habitat transitions within this group.

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