THE ENVIRONMENTAL QUALITY OF THE SEWAGEDISCHARGE AREA OF QINGDAO COVE--ACLADISTIC ANALYSIS

This study on the environmental quality of the Qingdao Cove intertidal zone sewage discharge area is based on data obtained from the December of 1989 and 1990 macrobenthos investigations there, and uses pollution indicator species and computer aided cladistic analysis to divide the area into a polluted area and a semi-polluted area. The study showed the environmental quality in 1990 improved over that in 1989.

THE PHYLOGENY OF YEASTS--A CLADISTIC ANALYSIS

Cladistic analysis was used to clarify the phylogeny of 16 genera of yeasts whose great morphological differences and inclusion in different classification systems resulted in controversies over the taxonomy of seven genera such as Crypeococcus, etc. Some scholars suggest that they belong to Ascomycetes. but others think they belong to fungi imperfecti. After comprehensive cladistic analysis of many genetic characters, the authors consider that the above-mentioned seven genera of yeasts developed in parallel with Ascomycetes so that they should belong to one and the same developmental system.

Latest progress in graptolitic phylogeny studies——Cladistic analysis of Ashgillian Dicellograptus

The graptolites studied here were collected from the Ashgillian Wufeng Formation in Wuning County, Jiangxi Province, which included 9 species of Dicellograptus, 2 species of Tangyagraptus and 1 species of Dicranograptus . The polarity and states of 8 selected characters are analyzed based on the morphological features and stratigraphic sequences of the 12 species and a parsimonious cladogram is reconstructed by using the monothetic method proposed by Camin and Sokal. A phyloneny tree of evolutionary significance formed by adding a time_axis to the cladogram indicates that the Ashgillian Dicellograptus in the investigated area includes two independent evolutionary lineages starting to diverge as early as in the Caradocian and, within the main lineage composed of the dicellograptids with square or subsquare basal portion, two clades represented respectively by Dicellograptus complexus and D. turgidus mark the highest stage of the Ashgillian dicellograptid evolution.

Romance of the three domains:how cladistics transformed the classifi cation of cellular organisms

Cladistics is a biological philosophy that uses genealogi-cal relationship among species and an inferred sequence of divergence as the basis of classifi cation.This review critically surveys the chronological development of bio-logical classification from Aristotle through our post-genomic era with a central focus on cladistics.In 1957,Julian Huxley coined cladogenesis to denote splitting from subspeciation.In 1960,the English translation of Willi Hennig’s 1950 work,Systematic Phylogenetics,was published,which received strong opposition from phenet-icists,such as numerical taxonomists Peter Sneath and Robert Sokal,and evolutionary taxonomist,Ernst Mayr,and sparked acrimonious debates in 1960-1980.In 1977-1990,Carl Woese pioneered in using small subunit rRNA gene sequences to delimitate the three domains of cellu-lar life and established major prokaryotic phyla.Cladistics has since dominated taxonomy.Despite being compatible with modern microbiological observations,i.e.organisms with unusual phenotypes,restricted expression of charac-teristics and occasionally being uncultivable,increasing recognition of pervasiveness and abundance of horizon-tal gene transfer has challenged relevance and validity of cladistics.The mosaic nature of eukaryotic and prokary-otic genomes was also gradually discovered.In the mid-2000s,high-throughput and whole-genome sequencing became routine and complex geneologies of organisms have led to the proposal of a reticulated web of life.While genomics only indirectly leads to understanding of func-tional adaptations to ecological niches,computational modeling of entire organisms is underway and the gap between genomics and phenetics may soon be bridged.Controversies are not expected to settle as taxonomic classifi cations shall remain subjective to serve the human scientist,not the classifi ed.

Phylogeny of Devonian Lycopsids Inferred from Bayesian Phylogenetic Analyses

To investigate the phylogeny of early lycopsids,cladistic analyses using both parsimony and Bayesian approaches are presented,with a data matrix of 33 morphological characters across 25 taxa. The resulting parsimony and Bayesian trees showed overall similarities in tree topologies.In the Bayesian tree,the Protolepidodendrales and the heterosporous lycopsids are recognized as two monophyletic groups,and within the latter group,the Isoetales sensu lato forms a subclade.This topology implies that the acquisition of a ligulate character evolved twice in the lycopsids,once in the protolepidodendralean Leclercqia Banks et al.,and once in the heterosporous lycopsid clade. Phylogenetic positions of several lycopsid plants previously reported from the Mid-Upper Devonian of South China,which have uncertain ordinal affinities,were estimated by the cladistic analyses;cf. Longostachys Xue et Hao,Longostachys Zhu et al.,Monilistrobus Wang et Berry,and Yuguangia Hao et al.fall well within the Isoetales clade,as earliest members of this order,while Minostrobus Wang and Wuxia Berry et al.are nested within the basal part of the heterosporous lycopsids.Bayesian analyses are a very useful approach in systematic studies and can be applied in analyzing paleobotanical data sets as well.

A preliminary molecular historical biogeography of Caragana (Leguminosae) based on ITS and trnL-F DNA sequence data

The nrDNA internal transcribed spacer (ITS) and cpDNA trnL-F internal spacer (IGS) sequence data of Caragana eight species and one outgroup Halimodendron halodendron, was employed to reconstruct a phylogenetic tree, then the area relationship was analyzed by means of component analysis (CA), Brooks parsimony analysis (BPA), and dispersal-vicariance analysis (DIVA), six areas were selected from two divided distributions of East Asia and Tethys in Caragana. The phylogenetic tree indicated that there were three distinctive groups, which were attributed to some morphological characters, first with pinnate foliage and deciduous rachis, second with palmate foliage and persistent sclerotic stick rachis, and third with pinnate foliage and persistent sclerotic stick rachis. The results of CA and BPA illustrated general area relationships. An explicit area relationship should be Altai-Sayan, Far East NE China and North China (Hengduan Mountains). DIVA recognized several explanatory vicariance and dispersal events. As the scenario of Caragana distribution pattern, it looks like the vicariance versus dispersal plays more important role. In vicaraince, there are not only the isolated far-distance vicariance, but also the adjacent vicariance especially a vicariance between Hengduan Mountains and North China.

Numerical Taxonomic Study of Some Tribes of Gramineae from Egypt

A systematic study for eleven tribes of Gramineae surveyed 34 characters including fruit morphology, fruit anatomy and palynology. The results were conducted to some numerical analysis aspects. On the basis of UPGMA (Unpaired Group Method of Average) clustering and PCA (Principal component analysis), the results show congruence between the UPGMA clustering and PCA method, in suggesting two major clads/groups and five subclads.

Determination of phylogenetic position of Pipizini (Diptera: Syrphidae): based on molecular biological and morphological data

Based on the sequence analysis of 5.8S subunit and internal transcribed spacers (ITS ) of ribosomal RNA gene (rDNA), the molecular phylogenetic tree of representative species of Pipizini and three groups of Syrphidae with different feeding habits (seven species belong to six genera) was constructed. Meanwhile, the phylogenetic tree of tribes (including Pipizini and other 17 tribes of Syrphidae) was constructed using morphological characteristics of adults and larvae and the number of chromosomes. Both the results show that the relationship between Pipizini and predatory groups is closer than that between Pipizini and saprophagous groups. So it is suggested that Pipizini be transferred from Milesiinae to Syrphinae.

Increasing the number of discrete character states for continuous characters generates well-resolved trees that do not reflect phylogeny

Since the introduction of the cladistic method in systematics,continuous characters have been integrated into analyses but no methods for their treatment have received unanimous support.Some methods require a large number of character states to discretise continuous characters in order to keep the maximum level of informa­tion about taxa differences within the coding scheme.Our objective was to assess the impact of increasing the character state number on the outcomes of phylogenetic analyses.Analysis of a variety of simulated datasets shows that these methods for coding continuous characters can lead to the generation of well-resolved trees that do not reflect a phylogenetic signal.We call this phenomenon the flattening of the tree-length distribution;it is influenced by both the relative quantity of continuous characters in relation to discrete characters,and the num­ber of characters in relation to the number of taxa.Bootstrap tests provide a method to avoid this potential bias.