中国与欧洲晚中新世猪类比较研究:生物地层学及古生态学

猪类对比研究表明,从晚中新世初期到晚中新世末(或上新世初期),中国与欧洲的古气候、古环境和猪类演化都受到了全球性自然变化的影响,有着相同或相似的发展经历。晚中新世早期(early Vallesian(MN9))中国与欧洲的猪类显示它们均受到先前来自南亚猪类的影响,南亚猪类可能通过东南亚扩散到中国南方,通过西亚扩散到欧洲。晚中新世中期(lateVallesian(MN10)and early Turolian(MN11)),中国和欧洲的猪类与南亚已基本没有交流,在各自地区相对独立地演化发展。晚中新世晚期(late Turolian(MN12、MN13))中国北方除了保留有从南方迁移来的种类外,欧洲的猪类也已出现,此时中国(北方)动物群与欧洲动物群关系较为密切。南亚动物群在晚中新世早期(或者更早些)似乎已经和中国及欧洲的动物群分离。受青藏高原隆升等自然因素的影响,晚中新世中后期中国南方的古环境有一个从较为封闭、湿热的森林类型向相对开阔、干冷稀树草原类型的演变过程,而在此期间北方的自然环境则可能是从早期的半干旱疏林草原逐步发展到晚中新世末期的湿润林地。晚中新世欧洲自然环境有一个与中国南方相似的变化过程,比较而言,晚中新世中后期欧洲的环境可能比中国北方更为开阔和干冷。古气候和古环境变化是影响晚中新世猪类分布演化的决定性因素。     

SUMMARY OF GREEN PLANT PHYLOGENY AND CLASSIFICATION

Abstract— A cladogram of green plants involving all major extant groups of green algae, bryophytes, pteridophytes, and seed plants is presented. It is partly based on contributions by B. Mishler and S. Churchill, H. Wagner, and P. Crane. The relationships of green plants to other green organisms ( Prochloron , euglenophytes) are discussed. The characters and subclades of the cladogram are briefly discussed, with an attempt to indicate weak points. The possibility of including some major extinct groups is considered. A cladistic classification consistent with the cladogram is presented. Grades are abandoned as taxa and major clades like the division Chlorophyta (green algae excluding micro-monadophytes and charophytes sensu Mattox and Stewart), the division Streptophyta (charophytes + embryophytes), the subdivision Embryophytina (land plants or embryophytes), the superclass Tracheidatae (tracheophytes), and the class Spermatopsida (seed plants) are recognized.     

THE AMINO ACID COMPOSITION OF FRESHWATER MOLLUSC SHELLS IN RELATION TO PHYLOGENY AND ENVIRONMENT

Quantitative thin layer chromatography of structural amino acidswas standardized for the study of shell proteins of 13 speciesof freshwater mollusc. There was slight intraspecific variationbetween individuals, particularly for tyrosine concentrations.No external periostracum was chemically identifiable in theshell of Lymnaea peregra (Müller) and this species showedsome amino acid heterogeneity in different parts of the shell.Despite these intraspecific variations, analysis of variancesuggested interspecific variation in concentrations for almostall the amino acids tudied. Cluster and principal componentsanalysis indicated that the amino acid composition did reflectphylogenetic affinity but that environmental factors were probablymore-important. (Received 5 August 1982; revised 5 August 1982;     

PHYLOGENY AND CLASSIFICATION OF THE PANDALOIDEA (CRUSTACEA, CARIDEA)

Abstract— A manual cladistic analysis, subsequently expanded with a PAUP computer analysis, was performed on 21 genera of the monophyletic taxon Pandaloidea. Morphological data were obtained from the literature for 146 of the 152 known species-group taxa and from specimens belonging to 11 genera and 15 species—those of Pantomus parvulus extending the known range from the North Western Atlantic to Uruguay. The taxon Physetocaridoidca was synonymized with Pandaloidea, and the genus Pandalopsis with “Pandalus”. I have rejected reversal hypotheses indicated by the computer for four transformation series and chosen a final cladogram of slightly different topology which is six steps longer than the shortest tree. The cladogram for 20 terminal taxa is based on 108 apomorphic characters, resolved into 155 steps (72 synapomorphies and 83 homoplasies and reversals). The following sequenced phylogenctic classification is proposed: Pandaloidea; Pandalidae; Pantominae subfam.n.; Notopandalus [N. magnoculus]; Peripandalus [P. serratus]; Pantomus; P. ajfinis; P. parvulus; Pandalinae; Austropandalini trib.n.; Austropandalus [A. grayi]; Pandalina; P. brevirostris; P. profunda; Pandalini; Dichdopandalus; D. bonnieri; D. leptorerus; Pandalus: “Plcsionikidae” [“Plesionika”]; Heterocarpidae [Heterocarpus]; Heterocarpoididae fam.n. [Heterocarpoides] [H. levicarina]; Dorodoteidae fam.n. [Dorodotes] [D. reflexus]; Thalassocarididae; Chlorotocus; C. crassicornis; C. novaezelandiae; Chlorotocoides [C. spinicauda]; Thalassocaris;, T. obscura; T. crimia; T. lucida; Physetocandidae; Stylopandalus [S. richardi]; Chlorotocella; C. gracilis; C. leptorhjnehus; Physetocaris [P. microphthalma]; Chlorocurtis [C. jactans]; Anachlorocurtis [A, commensalis]; Miropandalus [M. hardingi]. Quotation marks indicate taxa of uncertain systematic status. Square brackets indicate redundant, phylogenetically uninformative, genus and species-level taxa maintained in the classification to comply with the principle of binominal nomenclature.     

BIOVOLUME CALCULATION FOR PELAGIC AND BENTHIC MICROALGAE

Microalgal biovolume is commonly calculated to assess the relative abundance (as biomass or carbon) of co-occurring algae varying in shape and/or size. However, a standardized set of equations for biovolume calculations from microscopically measured linear dimensions that includes the entire range of microalgal shapes is not available yet. In comparison with automated methods, the use of microscopical measurements allows high taxonomic resolution, up to the species level, and has fewer sources of error. We present a set of geometric shapes and mathematical equations for calculating biovolumes of >850 pelagic and benthic marine and freshwater microalgal genera. The equations are designed to minimize the effort of microscopic measurement. The similarities and differences between our proposal for standardization and previously published proposals are discussed and recommendations for quality standards given.     

ON THE PHYLOGENY AND HIGHER CLASSIFICATION OF THE OLIGOCHAETA

Abstract— The 50 oligochaete taxa representing all families of “opisthoporous” oligochaetes (Aliuroididae, earthworms and aquatic “megadriles”) together with two representatives of the Haplotaxidac and three examples of “microdiles” were subjected to cladistic analysis using the PAUP program. Sixty-eight characters used in the analyses were derived from a comprehensive range of somatic and genital systems. The optimal result, in terms of maximal number of characters and taxa and of parsimony, produced two trees (consistency index 0.362) differing only in the placement of the monotypic clade for the family Lumbriculidae. From a line originating from the presumed octogonadial ancestor, the following branches were derived, in sequence from the basal to most derived (new taxa asterisked): subclass Randiellata* (order Randiellida*, Randiellidae); subclass Tubificata* (order Tubificida, Tubincidae, Naididae computed and others not computed); subclass Lumbriculata* (order Lumbriculida, Lumbriculidae); superorder Haplotaxidea* (order Haplotaxida, Haplotaxidae); order Moniligastrida (Moniligastridae); suborder Alluroidina (Aliuroididae and Syngenodrilidae); cohort Aquamegadrili* (with, in succession, superfamilice Sparganophiloidea, Sparganophilidae; Biwadriloidea, Biwadrilidac, and Almoidca—Lutodrilidac and Almidae, including Criodrilus); superfamily Eudriloidea*, superfamily Lumbricoidea and, as the adelphotaxon of the latter, the superfamily Megascolecoidea. Intermediate nodes were given the following names, with the adelpholaxon through to the Megascolecoidea, M, in parentheses: subclass Diplotesticulata (Haplotaxidea—M); superorder Metagynopohora* (Moniligastrida—M); order Opisthopora (Alluroidina M); suborder Crassiclitellata* (Aquamegadrili — M); cohort Terrimegadrili* (Ocnerodriloidea M); unnamed (Eudriloidea M); unnamed (Lumbricoidea and Megascolecoidea). Recognition of the Randiellata, which alone were added intuitively and not computed, and the position of the Lumbriculata, are tentative. Location of the Lumbricoidea as the adelphotaxon of a restricted Megascoecloidea is heuristic, but the alternative depiction of lumbricoids in some analyses, as the adelphotaxon of an ocnerodrilid-eudrilid-megascolecoid clade (the conventional Megascolecoidea s. lat.), is not conclusively dismissed.     

嵌套性:研究方法、形成机制及其对生物保护的意义

岛屿或者“生境岛”中的生物区系常常显示出一种嵌套结构 ,即物种较贫乏的岛屿中的物种是物种较丰富的岛屿中的物种的一个适当的子集 ,如果将各个岛屿中的生物区系排列起来就形成一个嵌套的序列。与种 面积关系一样 ,嵌套结构在很多生境类型和生物类群中也都存在。嵌套性对生物保护也有一定的意义 ,特别是与SLOSS争论 (是单个大的还是几个小的保护区能保护更多的物种 )有一定关系。在过去的十几年中 ,已经提出了一些方法 ,可以对嵌套性进行定量刻画和统计检验。同时 ,对嵌套性的形成机制也进行了大量的研究 ,其中选择性的迁移和选择性的灭绝是两个主要的原因。由于嵌套性分析只需要物种的存在 /不存在数据 ,使得很多调查数据都能够利用起来 ,因此 ,这是一个值得深入研究的领域     

PHYLOGENY AND CLASSIFICATION OF REEF‐BUILDING CORALLINE ALGAE (CORALLINALES,RHODOPHYTA)

The Corallinales includes ca. 40 genera of calcified red seaweeds. Species are of two distinct morphotypes; those that possess genicula (uncalcified nodes) and those that lack genicula. Most nongeniculate species take the form of crusts. The presence (or absence) of genicula, secondary pit connections, and tetrasporangial conceptacle features have traditionally been used as key characters for delimiting coralline subfamilies. In this study, nuclear encoded 18S and 26S rRNA gene sequences were determined and used to reexamine relationships among coralline taxa. Separate and combined phylogenetic analyses of these data yielded similar trees in which four major lineages are resolved. Heydrichia and Sporolithon (Sporolithaceae) are positioned at the base of the tree and appear to be distantly related to other species examined. Within the Corallinaceae, the nongeniculate Melobesioideae is resolved as a monophyletic group. All members of this subfamily produce mutiporate tetraspoangial conceptacles. The Corallinoideae, which are characterized by unizonate genicula, are resolved as sister to a clade containing species placed in the Lithophylloideae, Mastophoroideae and Metagoniolithoideae. The molecular data indicate that geniculate and nongeniculate species characterized by the presence of secondary pit connections are closely related. For example, both data sets robustly support a sister taxon relationship between Amphiroa and Titanoderma. Our results indicate that: 1) all taxa in which secondary pit connections are present should be referred to the Lithophylloideae and, 2) genicula are nonhomologous structures that are independently derived in Amphiroa, Lithothrix, Metagoniolithon and the last common ancestor of the Corallinoideae.     

THE DISPERSAL BARRIER IN THE TROPICAL PACIFIC: IMPLICATIONS FOR MOLLUSCAN SPECIATION AND EXTINCTION

Stretches of deep ocean constitute barriers to the dispersal of many shallow-water marine species in the tropical Pacific. The purpose of this study was to assess the selectivity of these barriers with respect to the habitat characteristics, adult size, and predation-related shell architecture of gastropods, and to explore the implications of this selectivity for macroevolutionary patterns of extinction and speciation. The dispersal barrier between continental islands (represented in my collections by species from eastern Indonesia, the southern Philippines, and the north coast of New Guinea) and the nearby oceanic Palau Islands was studied by evaluating the percentage of each architectural and habitat category that is present on the continental islands but missing in Palau. The barrier is significantly more effective against sand-dwelling species than against rock-dwellers, and among rock-dwellers it is most effective against aperturally unarmored taxa. Barriers between Palau and Guam, Guam and the Hawaiian Islands, and the Line Islands and the tropical Eastern Pacific are generally unselective with respect to substratum type and architecture. The fact that narrow-apertured species are less affected by the barrier between the continental islands and Palau than are other rock-dwelling gastropods is consistent with the interpretation that this group has been unusually resistant to extinction and highly susceptible to founder speciation when oceanic circulation is altered. These patterns of susceptibility and geographical distribution may explain why armored gastropods have increased in numbers relative to unarmored ones in the tropical Pacific during the Cenozoic.     

POST-LARVAL CEMENTATION IN THE OSTREIDAE AND ITS IMPLICATIONS FOR OTHER CEMENTING BIVALVIA

Despite the polyphyletic acquisition of the cemented habit inthe bivalves, the actual mechanism of post-larval cementationhas remained obscure. This study examines the mechanism of attachmentin the dissoconchs of members of the Ostreidae. It is demonstratedthat a thin periostracal sheet, preformed at the mantle margins,is secreted throughout the cementation process and that theeventual cement is calcareous rather than composed of mucopolysaccharide.The cement structure is reminiscent of ‘inorganic’diagenetic cavity fill cements. The composition of the cementis remarkably similar to that of the oyster shell, indicatingthat it is derived from the same extrapallial fluid. A mechanismis proposed to account for these observations, invoking a permeableperiostracum which allows the ‘leakage’ of extrapallialfluids. This means of cementation has interesting implicationsfor the evolution of the cemented habit in the bivalves, andin other encrusting taxa as well as for our understanding ofbiomineralization processes. ¹Present address: Department of Earth Sciences, University ofCambridge, Downing Street, Cambridge, CB23EQ (Received 29 September 1990; accepted 11 June 1991)     

布雷费尔德对真菌的进化观点在真菌分类中所起的影响

布雷费尔德(O. Brefeld)虽对真菌纯培养方法的改进和真菌发育与生理知识作出了不少贡献,但他的主要贡献还是对真菌系统发育的观点。按照他的这种观点,卵菌不是真正的真菌,它应与粘菌一起排除在真菌之外,而真正的真菌应从接合菌开始。他并将子囊菌和担子菌分别分为半子囊菌和真子囊菌,半担子菌和真担子菌。     

PHENOTYPIC PLASTICITY AND HETEROCHRONY IN CICHLASOMA MANAGUENSE (PISCES,CICHLIDAE) AND THEIR IMPLICATIONS FOR SPECIATION IN CICHLID FISHES

Cichlid fishes in African rift lakes have undergone rapid speciation, resulting in “species flocks” with more than 300 endemic species in some of the lakes. Most researchers assume that there is little phenotypic variation in cichlid fishes. I report here extensive phenotypic plasticity in a Neotropical cichlid species. I examined the influence of diet on trophic morphology during ontogeny in Cichlasoma managuense. Two groups of full siblings were fed two different diets for eight months after the onset of feeding; thereafter both groups were fed a common diet. Phenotypes that differed significantly at 8.5 months converged almost completely at 16.5 months. If feeding on two different diets is continued after 8.5 months, the phenotypes remain distinct. Differences in diet and possibly in feeding mode are believed to have caused these phenotypic changes. Phenotypic plasticity is described in terms of a qualitative model of heterochrony in which phenotypic change in morphology is explained as retardation of the normal developmental rate. If phenotypic expression of morphology is equally plastic in African cichlid species as it may be in the American cichlids, as exemplified by C. managuense, then taxonomic, ecological, and evolutionary analyses of “species flocks” may be in need of revision. However, Old World cichlids may be less phenotypically plastic than New World cichlids, and this may contribute to the observed differences in speciation rate and degree of endemism.     

COMPLEMENTARY SEX DETERMINATION IN HYMENOPTERAN PARASITOIDS AND ITS IMPLICATIONS FOR BIOLOGICAL CONTROL

In haplodiploid Hymenoptera, unfertilized eggs produce haploid males while fertilized eggs lead to diploid females under most circumstances. Diploid males can also be produced from fertilization under a system of sex determination known as complementary sex determination (CSD). Under single-locus CSD, sex is determined by multiple alleles at a single sex locus. Individuals heterozygous at the sex locus are female while hemizygous and homozygous individuals develop as haploid and diploid males, respectively. In multiple-locus CSD, two or more loci, each with two or more alleles, determine sex. Diploid individuals are female if one or more sex loci are het-erozygous, while a diploid is male only if homozygous at all sex loci. Diploid males are known to occur in 43 hym-enopteran species and single-locus CSD has been demonstrated in 22 of these species. Diploid males are either developmentally inviable or sterile, so their production constitutes a genetic load. Because diploid male production is more likely under inbreeding, CSD is a form of inbreeding depression. It is crucial to preserve the diversity of sex alleles and reduce the loss of genetic variation in biological control. In the parasitoid species with single-locus CSD, certain precautionary procedures can prevent negative effects of single-locus CSD on biological control.     

膜翅目寄生蜂的互补性别决定机制及其在生防上的意义(英文)

在膜翅目中 ,未受精卵形成单倍体的雄蜂 ,而在大多数情况下受精卵将产生双倍体的雌蜂。但是 ,因互补性别决定机制 (CSD)的作用 ,受精卵有时也会产生双倍体雄蜂。这种性别决定机制包括单位点的CSD和多位点的CSD。在单位点的CSD作用下 ,唯一的一个性位点上的多个等位基因决定后代个体的性别。性位点上杂合的个体将是雌性 ,半合或同型结合的个体将分别形成单倍体或双倍体的雄性。在多位点的CSD作用下 ,两个或两个以上的性位点控制后代的性别 ,每个性位点上包含两个或两个以上的等位基因。如果一个或一个以上的性位点是杂合的 ,形成的双倍体后代都是雌性的 ,但若是所有的性位点都为同型合子 ,则将产生双倍体的雄蜂。在膜翅目中 ,目前已知 4 3种具有双倍体雄蜂 ,其中 2 2种发现存在单位点的CSD ,但是多位点的CSD还有待于确认。双倍体的雄性个体或者不能存活 ,或者不育 ,这样的个体形成将对寄生蜂种群的增长带来一定的遗传负担。在生物防治上 ,保护寄生蜂种群的性等位基因的多样性及减少其遗传多异性的损失极其重要。如果利用具有单位点CSD的种类 ,采取一定的措施将可避免由于双倍体雄性的形成所带来的负面影响。