摘要:

AbstractIt is argued that both the principle of parsimony and the theory of evolution, especially that of natural selection, are essential analytical tools in phylogenetic systematics, whereas the widely used outgroup analysis is completely useless and may even be misleading.In any systematic analysis, two types of patterns of characters and character states must be discriminated which are referred to as completely and incompletely resolved. In the former, all known species are presented in which the characters and their states studied occur, whereas in the latter this is not the case.Dependent on its structure, a pattern of characters and their states may be explained by either a unique or byvariousconflicting, equally most parsimonious hypotheses of relationships. The so‐called permutation method is introduced which facilitates finding the conflicting, equally most parsimonious hypotheses of relationships. The utility of the principle of parsimony is limited by the uncertainty as to whether its application in systematics must refer to the minimum number of steps needed to explain a pattern of characterts and their states most parsimoniously or to the minimum number of evolutionary events assumed to have caused these steps. Although these numbers may differ, the former is usually preferred for simplicity.The types of outgroup analysis are shown to exist which are termed parsimony analysis based ontest samplesand cladistic type of outgroup analysis. Essentially, the former is used for analysing incompletely resolved patterns of characters and their states, the latter for analysing completely resolved ones. Both types are shown to be completely useless for rejecting even one of various conflicting, equally most parsimonious hypotheses of relationships.According to contemporary knowledge, this task can be accomplished only by employing the theory of evolution (including the theory of natural selection). But even then, many phylogenetic‐systematic problems will remain unsolved. In such cases, arbitrary algorithms like those offered by phenetics can at best offer pseudosolutions to open problems.Despite its limitations, phylogenetic systematics is superior to any kind of aphylogenetic systematics (transformed cladistics included) in approaching a (not: the) “general reference system” of or

ISSN:0947-5745    

DOI:10.1111/j.1439-0469.1993.tb00175.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractThe triplet consisting of two monophyletic taxa and one paraphyletic taxon as constructive element of the phylogenetic systemEvolution has produced very many novelties (apomorphies). Most of them are small and relatively inconstant, these are more or less indicative of the phylogenetic relationships between closely related species. They cannot be the constitutive character of a supraspecific taxon that exists since a long time and comprises many diversified species. Such a taxon of higher rank can only be characterized by an improbable, rare novelty that has developed only once and has been preserved in all descendent species. Two consecutive apomorphies of this persistent type (‘fixed apomorphies’) characterize three supraspecific taxa, the triplet “A”, “B” and “A minus B” (Fig. 1). The group “A minus B” is rejected in Hennig's theory because it is ‘paraphyletic’, but it is not an artefact created by the systematicist. It is an inevitable mathematical consequence of the differentiatison of the group “B” within the group “A”. Being the result of a subtraction, it is necessarily associated with the two monophyletic partners in the triplet, as it is delimited on one side by the synapomorphy of the group “A”, of which it is a part, and on the other side by the autapomorphy of the separate group “B”.Traditional classifications often include paraphyletic groupings that are inconsistent with phylogenetics, e. g. the Reptilia and the Apterygota. The fault in such cases is that these groups are extended beyond the limits of a triplet and cover more than a single interval between consecutive monophyletic taxa. Paraphyletic groups are admitted in the phylogenetic system only for bridging the gaps in our cladistic information.According to HENNIG'S theory, all supraspecific taxa should be arranged two by two as sister‐groups originating from one ancestral species and comprising all descendents of that species. The fixed evolutionary novelties which characterize higher supraspecific taxa are, however, rare and scattered. It is highly improbable that they have developed in sister species, therefore the taxa marked by them cannot be sister‐groups (except in very rare cases). In HENNIG'S earlier papers, e. g. in his system of Lepidoptera (1953: 46–49), the alleged ‘sister‐groups' are, in reality, the groups “B” and “A minus B” of a triplet (see Fig. 2). In his revised concept (1957 and later), two autapomorphic groups which are most closely related in the recent fauna (“B” and “C” in Fig. 3) are called ‘sister‐groups’. But these have originated independently from different ancestors in a plesiomorphic complex of extinct species and are more closely related to parts of this complex than to each other. True sister‐groups (“Bx” and “Cx” in Fig. 4) would be formed if these related plesiomorphic species were included, but this extension of the ’backward‘ border of the taxon is not justified by synapomorphy (in the terms of logic, it is a ’metabasis‘), and it would make the classification of fossil species impossible, unless these show at least one synapomorphy with either “B” or “C”. In the system of the recent fauna the sister‐groups are identical with the autapomorphic groups, because the plesiomorphic species are extinct.The natural system based on synapomorphies and autapomorphies is the triplet‐system as outlined in Figure 6. It is not a new type of classification, but its theoretical foundation was missing, and precise instructions were needed for its use in phylogenetics. The information obtained by HENNIG'S method is entirely preserved in this system and can be retrieved from it, and both recent and extinct species can be classified together. The disadvantage of the triplet‐system is that it contains twice as many taxa as HENNIG'S classification. This complexity will limit its use in the practice of taxonomy, but it may be simpli

ISSN:0947-5745    

DOI:10.1111/j.1439-0469.1993.tb00176.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractThe palatoquadrate inEusthenopterondisplays certain variation concerning the extent of its commissural lamina, and the presence of imprints of vessels and nerves on the outer surface of this middle part of the element. Comparison with some contemporary fishes revealed that branches of the arteria ophthalmica magna or of the ramus palatinus posterior VII could have produced these imprints. The grooves are connected with canals piercing the bone along its pars pterygoquadrata. Possible explanation is that the autopalatine and pterygoquadrate portions of the palatoquadrate were free in early developmental stages and later become interconnected by cartilage and bone. The dual nature of the palatoquadrate is shown to occur not only in the development of some Recent fishes, but in extinct groups (e. g., placoderms) as well.

ISSN:0947-5745    

DOI:10.1111/j.1439-0469.1993.tb00177.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractThe structure of the mating call of lake frogs (referred to asR. ridibunda) from 16 populations in Greece was analyzed for local variation using multivariate statistics. The populations of Thrace and of the island of Samothraki form a group giving the same type of mating call, whereas the mating call of the other populations differs in the degree of temperature dependence of four parameters, and specifically in the number of pulses/pulse group and pulse groups/call. Discriminant functions distinguish even single call series with a probability of 97%, intermediate mating calls are absent, and there is a significant, but slight differentiation of external morphological characters. These results have strong taxonomic implications. We conclude that the lake frogs of Greece comprise two species.The mating call of the lake frogs from Thrace resembles in all parameters that of theRana ridibundain the terra typica restricta (Guryev, CIS). Accordingly, the lake frogs of eastern Greece belong toR. ridibunda.The mating call of these lake frogs consists of 20 pulses/pulse group and of 7 pulse groups/call on the average. Most of Greece is inhabited by the second taxon,Rana balcanicasp. n. Its mating call is characterized by 27 pulses/pulse group and 4 pulse groups/call on the average.The two species in Greece do not differ with respect to coloration and size, but several standardized indices vary significantly: body length/digitus primus length; body length/callus internus length; body length/snout‐eye distance; body length/tympanum diameter; tibia length/callus internus length; maximal head width/snout‐eye dista

ISSN:0947-5745    

DOI:10.1111/j.1439-0469.1993.tb00178.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

AbstractAs a contribution to their taxonomy, population genetic data on zoo‐living anoas are reported, and a review of the history of the captive stock is provided. Four different chromosome numbers of 44, 45, 47 and 48 chromosomes have been found, respectively, when karyotyping captive anoas descending from three breeding lines. The number of chromosome arms is 60 throughout, indicating that Robertsonian rearrangements are responsible for this cytogenetic variation. An electrophoretic comparison of isozymes and blood proteins representing 21 genetic loci revealed polymorphism in seven loci: haemoglobin, glyoxalase, superoxide dismutase, phosphoglucomutase, carbonic anhydrase, glucose phosphate isomerase, and an unidentified acid serum protein. Considering the small number of founder specimens and subsequent inbreeding, allozyme variability appears fairly high in anoas. Genetic distances between zoo populations amount to 0.0505 or less. Southern blot hybridizations of restricted DNA from anoas and African buffaloes with a probe from the DRB‐like region of the chimpanzee's MHC class II genes also indicate a low degree of genetic differentiation between mountain and lowland anoas. The relevance of these genetic data for the taxonomic classification of mountain and lowland anoas, and for the conservation of anoas by captive breeding is discus

ISSN:0947-5745    

DOI:10.1111/j.1439-0469.1993.tb00179.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY

摘要:

King, M.: Animal Cytogenetics. Vol. 4, Chordata 2: Amphibia. Ed. by B. John. Berlin und Stuttgart:Christidis, L.: Animal Cytogenetics. Vol.4, Chordata 3B: Aves. Ed. by B. John. Berlin und Stuttgart: Gebrüder Bornträg

ISSN:0947-5745    

DOI:10.1111/j.1439-0469.1993.tb00180.x

出版商:Blackwell Publishing Ltd    

年代:1993

数据来源: WILEY