Summary: The program MRBAYES performs Bayesian inference of phylogeny using a variant of Markov chain Monte Carlo. Availability: MRBAYES, including the source code, documentation, sample data files, and an executable, is available at http://brahms.biology.rochester.edu/software.html.

http://webpages.icav.up.pt/PTDC/BIA-BEC/104097/2008/23.pdf

MRBAYES: Bayesian inference of phylogenetic trees

抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

mothur aims to be a comprehensive software package that allows users to use a single piece of software to analyze community sequence data. It builds upon previous tools to provide a flexible and powerful software package for analyzing sequencing data. As a case study, we used mothur to trim, screen, and align sequences; calculate distances; assign sequences to operational taxonomic units; and describe the alpha and beta diversity of eight marine samples previously characterized by pyrosequencing of 16S rRNA gene fragments. This analysis of more than 222,000 sequences was completed in less than 2 h with a laptop computer.

/pdf/introducing-mothur-open-source-platform-independent-3tr77w6374.pdf

Introducing mothur: Open-Source, Platform-Independent, Community-Supported Software for Describing and Comparing Microbial Communities

Motivation: DnaSP is a software package for a comprehensive analysis of DNA polymorphism data. Version 5 implements a number of new features and analytical methods allowing extensive DNA polymorphism analyses on large datasets. Among other features, the newly implemented methods allow for: (i) analyses on multiple data files; (ii) haplotype phasing; (iii) analyses on insertion/deletion polymorphism data; (iv) visualizing sliding window results integrated with available genome annotations in the UCSC browser.

Availability: Freely available to academic users from: http://www.ub.edu/dnasp

Contact: [email protected]

DnaSP v5

With its theoretical basis firmly established in molecular evolutionary and population genetics, the comparative DNA and protein sequence analysis plays a central role in reconstructing the evolutionary histories of species and multigene families, estimating rates of molecular evolution, and inferring the nature and extent of selective forces shaping the evolution of genes and genomes. The scope of these investigations has now expanded greatly owing to the development of high-throughput sequencing techniques and novel statistical and computational methods. These methods require easy-to-use computer programs. One such effort has been to produce Molecular Evolutionary Genetics Analysis (MEGA) software, with its focus on facilitating the exploration and analysis of the DNA and protein sequence variation from an evolutionary perspective. Currently in its third major release, MEGA3 contains facilities for automatic and manual sequence alignment, web-based mining of databases, inference of the phylogenetic trees, estimation of evolutionary distances and testing evolutionary hypotheses. This paper provides an overview of the statistical methods, computational tools, and visual exploration modules for data input and the results obtainable in MEGA.

/pdf/mega3-integrated-software-for-molecular-evolutionary-1hk8vjhymf.pdf

MEGA3: Integrated software for Molecular Evolutionary Genetics Analysis and sequence alignment

MacClade is a computer program, with accompanying manual, that provides theory and tools for the graphic and interactive analysis of molecular and morphological data, phylogeny, and character evolution. Systematists and other evolutionary biologists can use its flexible tools to analyse phylogeny and character evolution, yet its ease of use allows beginning students to grasp phylogenetic principles in an interactive environment.

MacClade: Analysis of phylogeny and character evolution

Exploration of the relationship between gene trees and their containing species trees leads to consideration of how to reconstruct species trees from gene trees and of the concept of phylogeny as a cloud of gene histories. When gene copies are sampled from various species, the gene tree relating these copies might disagree with the species phylogeny. This discord can arise from horizontal transfer (including hybridization), lineage sorting, and gene duplication and ex- tinction. Lineage sorting could also be called deep coalescence, the failure of ancestral copies to coalesce (looking backwards in time) into a common ancestral copy until deeper than previous speciation events. These events depend on various factors; for instance, deep coalescence is more likely if the branches of the species tree are short (in generations) and wide (in population size). A similar dependence on process is found in historical biogeography and host-parasite relation- ships. Each of the processes of discord could yield a different parsimony criterion for reconstruct- ing the species tree from a set of gene trees: with horizontal transfer, choose the species tree that minimizes the number of transfer events; with deep coalescence, choose the tree minimizing the number of extra gene lineages that had to coexist along species lineages; with gene duplication, choose the tree minimizing duplication and/or extinction events. Maximum likelihood methods for reconstructing the species tree are also possible because coalescence theory provides the prob- ability that a particular gene tree would occur given a species tree (with branch lengths and widths specified). In considering these issues, one is provoked to reconsider precisely what is phylogeny. Perhaps it is misleading to view some gene trees as agreeing and other gene trees as disagreeing with the species tree; rather, all of the gene trees are part of the species tree, which can be visualized like a fuzzy statistical distribution, a cloud of gene histories. Alternatively, phylogeny might be (and has been) viewed not as a history of what happened, genetically, but as a history of what could have happened, i.e., a history of changes in the probabilities of inter- breeding. (Biogeography; coalescence; coevolution; evolution; gene duplication; gene genealogy; gene trees; horizontal transfer; hybridization; lineage sorting; parsimony; phylogeny; species con- cepts; species trees; tree reconciliation.)

/pdf/gene-trees-in-species-trees-3saat11ld6.pdf

Gene Trees in Species Trees

We compare the utility of two methods for estimating the average levels of gene flow from DNA sequence data. One method is based on estimating FST from frequencies at polymorphic sites, treating each site as a separate locus. The other method is based on computing the minimum number of migration events consistent with the gene tree inferred from their sequences. We compared the performance of these two methods on data that were generated by a computer simulation program that assumed the infinite sites model of mutation and that assumed an island model of migration. We found that in general when there is no recombination, the cladistic method performed better than FST while the reverse was true for rates of recombination similar to those found in eukaryotic nuclear genes, although FST performed better for all recombination rates for very low levels of migration (Nm = 0.1).

/pdf/estimation-of-levels-of-gene-flow-from-dna-sequence-data-4946sun8al.pdf

Estimation of levels of gene flow from DNA sequence data.

Part I Introducing MacClade: introduction - a tutorial overview of MacClade. Part II Phylogenetic theory: a phylogenetic perspective an introduction to phylogeny reconstructing character evolution using parsimony stratigraphic parsimony Part III Using MacClade: using MacClade on your Macintosh managing data files importing and exporting text files the data editor assumptions about characters trees and tree manipulation tracing character evolution basic tree and character statistics charting tree and character statistics continuous characters patterns of correlated character evolution generating random data and random trees using MacClade with molecular data recording your work. Appendix: file format.

Macclade: Analysis of Phylogeny and Character Evolution/Version 3

-Methods that use outgroups in the reconstruction of phylogeny are described and evaluated by the criterion of parsimony. By considering the character states and relationships of outgroups, one can estimate the states ancestral for a study group or ingroup, even when several character states are found among the outgroups. Algorithms and rules are presented that find the most parsimonious estimates of ancestral states for binary and multistate characters when outgroup relationships are well resolved. Other rules indicate the extent to which uincertainty about outgroup relationships leads to uncertainty about the ancestral states. The algorithms and rules are based on "simple parsimony" in that convergences and reversals are counted equally. After parsimony is measured locally among the outgroups to estimate ancestral states, parsimony is measured locally within the ingroup, given the ancestral states, to find the ingroup cladogram. This two-step procedure is shown to find the ingroup cladograms that are most parsimonious globally; that is, most parsimonious when parsimony is measured simultaneously over the ingroup and outgroups. However, the two-step procedure is guaranteed to achieve global parsimony only when: (a) outgroup relationships are sufficiently resolved beforehand; (b) outgroup analysis is taken to indicate the state not in the most recent common ancestor of the ingroup, but in a more distant ancestor; and (c) ancestral states are considered while the ingroup is being resolved, not merely added afterward to root an unrooted network. The criterion of global parsimony is then applied to evaluate procedures used when outgroup relationships are poorly resolved. The procedure that chooses as ancestral the state occurring most commonly among the outgroups can sometimes yield cladograms that are not globally parsimonious. By the criterion of global parsimony, the best procedure is one that simultaneously resolves the outgroups and ingroup with the data at hand. Finally, simple parsimony can choose among competing hypotheses, but it often fails to indicate how much confidence can be placed in that choice. [Phylogeny reconstruction; cladistic methods; outgroup analysis; character polarity; parsimony.] This paper explores the use of outgroup analysis in phylogeny reconstruction. When reconstructing a phylogeny, a systematist asks: Given a group of organisms (the ingroup), what are the monophyletic subgroups? If the members of a subgroup share a character state that is derived within the group, the monophyly of this subgroup is corroborated (Hennig, 1966; Wiley, 1975). Hence, systematists attempting to infer phylogenies have sought methods for determining whether a given character state is derived (apomorphic) or ancestral (plesiomorphic). Many methods for assessing the evolutionary polarity of characters have been proposed, including outgroup analysis, ingroup analysis, the ontogenetic method, and the paleontological method. These approaches have been reviewed recently by Crisci and Stuessy (1980), de Jong (1980), Stevens (1980), Arnold (1981), Nelson and Platnick (1981), and others. The methods perhaps most widely accepted today are outgroup analysis and the ontogenetic method, the relative merits of which are still being debated (contrast Nelson [1978] and Patterson [1982] with Lundberg [1973], Wheeler [1981] and Voorzanger and van der Steen [1982]). In its simplest form, outgroup analysis can be summarized by the following rule (Watrous and Wheeler, 1981): For a given character with two or more states within a group, the state occurring in related groups is assumed to be the plesiomorphic state. This rule is inadequate, however, when characters vary among the related groups (the outgroups). Arnold (1981) and Farris (1982) have dealt with some cases of

Wayne P. Maddison

Papers

MacClade: Analysis of phylogeny and character evolution

Gene Trees in Species Trees

Estimation of levels of gene flow from DNA sequence data.

Macclade: Analysis of Phylogeny and Character Evolution/Version 3

Outgroup analysis and parsimony