K.S.BAIKOV1, E.V.BAIKOVA1, A.A.ZVEREV2. Modeling of phylogenetic relations in spurges (Euphorbia, section Tulocarpa) from Northern and Northeast Asia.
Modeling phylogenetic relations between 15 species of genus Euphorbia from section Tulocarpa is executed by method SYNAP using 18 elementary evolutionary vectors. The model for taxa connection is the next: unstrict dichotomy (1), priority of occurrence of a new state (2), weighing of vectors, reversion equal minus 1. The choice of this model is caused by recent active speciation in this section. Three groups are good limited on the scheme. First group unites Euphorbia soongarica, E. semivillosa, E. lamprocarpa by 5-8 rays of terminal umbel, 3-5 external raylet-leaves, extended mushroom-shaped stigmata. Tubercles on fruits are here in convertible state. The second group includes species having conical and cylindrical tubercles on fruits: E. lutescens and E. macrorhiza with 2-4(5) short rays of terminal umbel, 3-4 external raylet-leaves; E. lucorum, E. pekinensis, E. alatavica having 5 rays of terminal umbel, three external raylet-leaves, small apical stigmata. Reduction in number of external ray-leaves from three (E. subamplexicaulis, E. buchtormensis) up to two takes place in the third group: species with five rays of terminal umbel are separated from species with 2-4 rays of umbel (E. alpina, E. jenisseiensis, E. pachyrhiza). The received phylogenetic scheme has correlations with ecological and geographical features of species. It may be used for description of low-level species groups, subsection delimitation, development of natural system of section Tulocarpa. The research is supported by grants of RFBR (98-04-49459, 01-04-49528) and Presidium of Siberian Branch of RAS (competition of the young scientists, integrative project №66)
1Central Siberian botanical garden SB RAS, Zolotodolinskaya, 101, Novosibirsk, 630090, fax 3832-301986, e-mail: baikov@csbg.nsc.ru
2Tomsk State University, Lenin Prospect, 36, Tomsk, 634050, fax 3822-410690, e-mail: zverev@ecos.tsu.ru
I.Ya. PAVLINOV. On "a good" and "a harm" of formalized models in phylogenetics.
More or less formalized models constitute necessary elements of all analytical procedures in phylogenetic reconstructions. These models are of two types, dynamic and static ones. Dynamic models refer to "evolutionary scenarios" including some statements about properties of phylogenetic process. They define explicitly initial and boundary conditions of phylogenetic reconstructions. Static models contain some statements about structure of similarity and kinship relationships and allow to elaborate numerical methods of their evaluation. Due to uniformity of models and methods rooted in them, results of phylogenetic reconstructions obtained for different groups by different authors based on different characters become both comparable and repeatable. This also allows to assess correctness of the reconstructions from the standpoint of some unified criteria. On the other hand, the uniformity contradicts to widely acknowledged facts of specificity of "evolutionary faith" of both different groups (e.g. prokaryotes and higher eukaryotes) and different structures (e.g. morphological and biochemical ones). It is evident that application of the same models makes it impossible to reveal this specificity. Thus, uniqueness of "evolutionary faiths" calls for elaboration of specific models for particular groups and structures. From this viewpoint, application of the same numerical methods and construing general cladograms based on "principle of global parsimony" for all living beings are not fully correct. Contradiction between uniformity of models and uniqueness of "evolutionary faiths" provides serious epistemological problem that has no resolution by now.
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