壳斗科的地质历史及其系统学和植物地理学意义

在收集整理现有壳斗科化石资料的基础上,讨论了壳斗科及其各属的起源时间、地史分布和地史 演替过程以及这些化石资料在系统学和植物地理学上的意义。白垩纪尚无壳斗科可靠的大化石记录, 微化石需要进一步研究才能确定亲缘关系以及古新世壳斗科已经分化出两个类群。从以上这些事实推 论壳斗科起源于白垩纪晚期,而壳斗科现代各属出现的时间应不晚于古新世。最早发现的壳斗科化石和现代栗亚科和水青冈亚科在形态结构上非常相似,这一事实表明,壳斗科分为两个亚科的观点更接近客观事实。在水青冈亚科中,三棱栎类的化石最早出现;在栎属中,青冈亚属更接近祖先类群;在地史中全缘栎类较具齿栎类出现早,粗齿的落叶栎类出现最晚。三棱栎属、栲属和石栎属的化石在老第三纪出现于北美和欧洲的事实说明,北美、欧洲和东亚在老第三纪时有一个相通的壳斗科植物区系。南美的三棱栎是通过北美进入南美的。中国横断山、欧洲地中海沿岸和北美西北部有一类形态特征相似、亲缘关系相近的硬叶栎类,它们之间有相同的地质演替历史,它们现代分布边界可能就是古地中海的边界。美洲的栎类有两个来源,常绿硬叶栎类是通过古地中海沿岸而经北美-欧洲陆桥到达的,落叶栎类则是在中新世以后通过白令海峡到达的。     

Embryology and systematics of Euphorbiaceaesens. lat.: a review and perspective

Based on a literature survey, we present a review of the embryology of Euphorbiaceaesensu Webster (with about 8,000 species in five subfamilies), which are one of the largest and most diversified families and have often been considered heterogenous. Nearly 40% of over 110 publications available for the whole family is concerned with a single genusEuphorbia, so that the current level of our knowledge on the embryology of Euphorbiaceae is very poor. Nevertheless we found that, contrary to a conclusion recently published by other authors, available information does not provide evidence to support a monophyly of Euphorbiaceae. Our analysis further suggested that only the following five of over 50 embryological characters of ovules and seeds are likely to be useful for comparison between and within subfamilies: (1) the presence or absence of vascular bundles in the inner integument; (2) whether the inner integument is thick or thin (probably useful only in Phyllanthoideae); (3) whether ovules or seeds are pachychalazal or not; (4) whether seeds are arillate or not; (5) whether an exotegmen is fibrous or not. On the basis of these five characters, a consistency and diversity of individual subfamilies was discussed. The need of further extensive studies on the five characters using herbarium specimens, particularly in genera of Phyllanthoideae, Oldfieldioideae and Acalyphoideae, was also discussed.     

我国放线菌系统学研究历史、现状及未来发展趋势

放线菌系统学是以实现对放线菌进行分类、鉴定、命名为目标的基础学科, 因此它是放线菌资源研究和开发利用的重要理论基础。自20世纪50年代起, 我国放线菌系统学的奠基人阎逊初院士及同事们就开创了我国放线菌系统学的研究, 经过近六十年、几代人的艰苦努力, 我国放线菌系统学工作者在国际微生物系统学权威杂志(International Journal of Systematics and Evolutionary of Microbiology, IJSEM)发表的有关放线菌新分类单元的论文数量连续十年排名稳居前列, 部分学者在国际上发表的某些改良的分类技术和新修订的分类系统等为国际同行所广泛采用, 这些均标志着我国放线菌系统学研究在国际上已成为微生物系统学界的一支重要力量。本文全面介绍了我国放线菌系统学研究的发展历程, 同时对其发展现状给予理性分析, 并就未来发展方向进行了展望。     

Cryptosporidium systematics and implications for public health

There is controversy in the taxonomy of Cryptosporidium parasites and the public health significance of Cryptosporidium isolates from various animals. Recent advances in molecular characterization of Cryptosporidium parasites have allowed the re-examination of species structure of the genus Cryptosporidium. Non-parvum Cryptosporidium spp and new C. parvum genotypes in immunocompromised humans can now be clearly detected. In this article, Lihua Xiao and colleagues summarize the current biological and molecular evidence for different Cryptosporidium spp, and the public health importance of these species and new C. parvum genotypes.     

A brief history and revision of the systematics of the cladid crinoid Sinocrinus

The erisocrinid Sinocrinus differs from other erisocrinid genera (Erisocrinus and Exaetocrinus) by possessing a rounded, bowl-shaped cup, bearing tumid cup plates with impressed sutures. Sinocrinus Tien, 1926 is refined using Principal Component Analysis and neighborhood cluster analysis. The genotype of Sinocrinus, S. microgranulosus Tien, 1926, is a junior subjective synonym of S. granulatus (Wanner, 1924). Sinocrinus [Erisocrinus] stefaninii (Yakovlev, 1934) is a junior synonym of Sinocrinus lichengensis Tien, 1926 and S. asymmetricus Strimple and Watkins, 1969 is the junior synonym of S. sheareri Strimple and Watkins, 1969. Other valid species include: S. [Erisocrinus] cernuus (Trautschold, 1867); S. [Erisocrinus] obliquus (Wanner, 1916); S. houkouensis Tien, 1926; S. nodosus Tien, 1926; S. [Erisocrinus] stefaninii (Yakovlev, 1934). Because of its refined inclusiveness, the temporal span of the genus now extends from the Late Carboniferous (Moscovian) through the early Permian (Sakmarion). This study also widens the current geographic range of Sinocrinus, with specimens collected across a wider span of Eurasia.     

Claims and limits of phylogenetic systematics1

Within the methodology of phylogenetic systematics four hierarchic levels are distinguished: the “Central Claim” (to reconstruct phylogeny), methodoloical postulate (to conclude analysis with a purely dichotomous cladogram if ever possible), method (search for sister-group relationships by character analysis), and “Taxonomic Principle” (establishment of a classification reflecting merely the recognized genealoy). Certain limits of applicability and reliability of traditional phylogenetic systematics are specified: genealogy can only be analysed among taxa with perceptible evolutionary novelties; reticulated genealogy is not yet regarded; events other than cladogenetic ones cannot be recognised. Phylogenetic systematics is an independent method which has not been absorbed by any type of “pattern” or “transformed” cladism. Phylogenetic systematics relies on the theory of evolution, which does not lead into circularity, since phylogenetic systematics does not claim to prove or to explain evolution whatsoever.     

Cranial endocast of Anagale gobiensis (Anagalidae) and its implications for early brain evolution in Euarchontoglires

Anagalids are an extinct group of primitive mammals from the Asian Palaeogene thought to be possible basal members of Glires. Anagalid material is rare, with only a handful of crania known. Here we describe the first virtual endocast of an anagalid, based on the holotype of Anagale gobiensis (AMNH 26079; late Eocene, China), which allows for comparison with published endocasts from fossil members of modern euarchontogliran lineages (i.e. primates, rodents, lagomorphs). The endocast displays traits often observed in fossorial mammals, such as relatively small petrosal lobules and a low neocortical ratio, which would be consistent with previous inferences about use of subterranean food sources based on heavy dental wear. In fact, Anagale gobiensis has the lowest neocortical ratio yet recorded for a euarchontogliran. This species was olfaction-driven, based on the relatively large olfactory bulbs and laterally expansive palaeocortex. The endocast supports previous inferences that relatively large olfactory bulbs, partial midbrain exposure and low encephalization quotient are ancestral for Euarchontoglires, although the likely fossorial adaptations of Anagale gobiensis may also partly explain these traits. While Anagale gobiensis is a primitive mammal in many aspects, some of its derived endocranial traits point towards a new, different trajectory of brain evolution within Euarchontoglires.     

Lung morphology in rodents (Mammalia, Rodentia) and its implications for systematics

A new nomenclature of the lung lobes and of the bronchial tree is presented, with which the lungs in 40 species of 11 rodent families are described. Whole, fixed lungs and silicone casts of the bronchial tree are tested for 23 characters, based on the distribution of lung lobes, the number and geometry of first order bronchi, the pulmonary blood supply, and lung symmetry. Ten lung morphotypes are recognized, seven of them representing one or more families: Castor type (Castoridae), Cryptomys type (Bathyergidae), Ctenodactylus type (Ctenodactylidae), Eliomys type (Gliridae), Myocastor type (Myocastoridae), Octodon type (Octodontidae and Echimyidae) and Rattus type (Sciuridae, Muridae pt. and Dipodidae). The Hydromys type is found only in Hydromys chrysogaster (Muridae), while Galea type A and B both appear in Galea musteloides (Caviidae). The data are phylogenetically analyzed by the program PAUP 4.0 using as outgroup Lagomorpha or Insectivora. On the species level, there are no well-resolved cladograms. On the family level, the cladograms do not contradict traditional rodent systematics with one exception: the Caviidae do not fall within Caviomorpha or even within the Hystricomorpha, but form a sister group to Dipodidae (Myomorpha). This appears to be a result of convergence. The lungs of Gliridae are more similar to those of Muridae than to those of Sciuridae. Included in the ingroup, Oryctolagus (Lagomorpha) forms a clade with Caviidae + Dipodidae. Thus, the "Glires hypothesis" is neither supported nor refuted.     

Relative brain size in monkeys and prosimians

Prosimians have smaller brains relative to their body sizes than do monkeys. Brain and body weights, however, are associated not only on the basis of the brain integrating sensorimotor functions, but also on the basis of the body's requirement to support the energetic needs of the brain. Prosimians differ from monkeys in that they have lower rates of oxygen turnover. When body size is adjusted for its rate of oxygen turnover, monkeys and prosimians have equivalent relative brain sizes. A consideration of the brain's energy requirements helps to clarify brain-body relationships.     

Workshop on barcoded DNA: application to rotifer phylogeny,evolution, and systematics

DNA barcoding is the use of segments of gene sequences to assign individual organisms to species. Thus it can be used to define species and to identify specimens. Barcoding has been applied as an aid to systematics with little controversy in both monogonont and bdelloid rotifers, and also in environmental sequencing projects designed to determine the diversity of microscopic organisms. In contrast, a great deal of controversy has arisen over the creation of the Consortium for the Barcode of Life, a major initiative to barcode all the species in several major groups of animals, with the long-range goal of barcoding all species of organisms. This is a very brief review of DNA barcoding, especially as applied to rotifers, and a summary of the results of a workshop held at the 11th International Workshop on Rotifera. Guest editors: S. S. S. Sarma, R. D. Gulati, R. L. Wallace, S. Nandini, H. J. Dumont and R. Rico-Martínez Advances in Rotifer Research     

Molecular phylogeny and systematics of the Barbinae (Teleostei: Cyprinidae) in China inferred from mitochondrial DNA sequences

The taxonomy and phylogeny of the Chinese species of the Barbinae (Cypriniformes) has a confusing history. In this study, partial sequences of four mitochondrial genes (cyt b, COI, ND4 and 16S rRNA) from 75 Barbinae species and 38 outgroup species were used to investigate the taxonomy and phylogeny within the Barbinae in China. The monophyly of Neolissochilus, Sikukia and Tor are not supported. Neolissochilus benasi might represent a new genus, and Tor hemispinus and Tor qiaojiensis should be moved into Neolissochilus. Sikukia flavicaudata is not Sikukia species. Puntius paucimaculatus might be a synonym of Puntius semifasciolatus. Puntius semifasciolatus does not belong to Puntius. Onychostoma barbatum might consist of more than one species. Our molecular results corroborate that Acrossocheilus stenotaeniatus is a synonym of Acrossocheilus longipinnis. Finally, Barbonymus gonionotus from Menglun, Yunnan should be Poropuntius huangchuchieni.     

Patterns of differences in brain morphology in humans as compared to extant apes

Although human evolution is characterized by a vast increase in brain size, it is not clear whether or not certain regions of the brain are enlarged disproportionately in humans, or how this enlargement relates to differences in overall neural morphology. The aim of this study is to determine whether or not there are specific suites of features that distinguish the morphology of the human brain from that of apes. The study sample consists of whole brain, in vivo magnetic resonance images (MRIs) of anatomically modern humans (Homo sapiens sapiens) and five ape species (gibbons, orangutans, gorillas, chimpanzees, bonobos). Twenty-nine 3D landmarks, including surface and internal features of the brain were located on 3D MRI reconstructions of each individual using MEASURE software. Landmark coordinate data were scaled for differences in size and analyzed using Euclidean Distance Matrix Analysis (EDMA) to statistically compare the brains of each non-human ape species to the human sample. Results of analyses show both a pattern of brain morphology that is consistently different between all apes and humans, as well as patterns that differ among species. Further, both the consistent and species-specific patterns include cortical and subcortical features. The pattern that remains consistent across species indicates a morphological reorganization of 1) relationships between cortical and subcortical frontal structures, 2) expansion of the temporal lobe and location of the amygdala, and 3) expansion of the anterior parietal region. Additionally, results demonstrate that, although there is a pattern of morphology that uniquely defines the human brain, there are also patterns that uniquely differentiate human morphology from the morphology of each non-human ape species, indicating that reorganization of neural morphology occurred at the evolutionary divergence of each of these groups.     

The relevance of metrical, chromosomal and allozyme variation to the systematics of the genus Mus

The contribution of metrical, karyological and biochemical techniques towards taxonomic understanding is considered with respect to (1) the delimitation of species; (2) the classification of species at generic level; and (3) subspecific variation. All these techniques are useful for the discrimination of sibling species, with metrical discriminants especially important in helping to establish the geographical limits of species, being applicable to museum collections and to fossil material. In classification at the generic level multivariate morphometric analysis is of very limited value, but karyology and allozyme studies can make important contributions provided the majority of relevant species are examined. All techniques are relevant to establishing the major aspects of subspecific variation, for which formal subspecific nomenclature is rarely appropriate. Problems of extrapolation from inadequate samples are just as acute when using these techniques as with more traditional taxonomy based on morphology. Clear presentation of results in the form of data matrices and dendrograms is important in facilitating the integration of data into a useful taxonomic system.     

Cultural evolution: implications for understanding the human language faculty and its evolution

Human language is unique among the communication systems of the natural world: it is socially learned and, as a consequence of its recursively compositional structure, offers open-ended communicative potential. The structure of this communication system can be explained as a consequence of the evolution of the human biological capacity for language or the cultural evolution of language itself. We argue, supported by a formal model, that an explanatory account that involves some role for cultural evolution has profound implications for our understanding of the biological evolution of the language faculty: under a number of reasonable scenarios, cultural evolution can shield the language faculty from selection, such that strongly constraining language-specific learning biases are unlikely to evolve. We therefore argue that language is best seen as a consequence of cultural evolution in populations with a weak and/or domain-general language faculty.     

The fossil evidence of anthropoid brain evolution

The endocast of Aegyptopithecus, a 27 million year old ape, reveals that its brain was advanced over that of prosimians and comparable to that of modern anthropoids in relative size and in having expanded visual cortex, reduced olfactory bulbs, and a central sulcus separating primary somatic sensory and motor cortex. The early appearance of those features suggests that they may have been among the adaptations responsible for the evolution of anthropoids from prosimian ancestors. The frontal lobe was relatively smaller in Aegyptopithecus than in modern anthropoids. An endocast of Dolichocebus, one of the oldest known New World monkeys (25–30 million years old), reveals visual cortex expanded as in modern anthropoids. The 19 million year old Napak frontal bone displays a hominoid rather than cercopithecoid sulcal pattern. An 18 million year old endocast of the ape Dryopithecus (Proconsul) was neither monkey-like nor primitive, as originally described, but rather apelike and essentially modern in all observable features. The oldest undoubted Old World monkey endocast, from nine million year old Mesopithecus, reveals that the brain was modern in sulcal pattern and proportions. The sulcal pattern was like that of modern colobines, but that appears to be the more primitive condition, from which features characteristic of modern cercopithecine brains have evolved. The brain of six million year old Libypithecus was similar to that of Mesopithecus. A two million year old endocast of “Dolichopithecus” arvernensis displays a modern cercopithecine sulcal pattern.     

The calcaneus of Australopithecus afarensis and its implications for the evolution of bipedality

Calcanei from African apes, modern humans, and Australopithecus afarensis are compared to investigate the anatomical and mechanical changes that occurred in this bone as a result of the transition to terrestrial bipedality. Features analyzed include the cross-sectional area and volume of the calcaneal tuber, the geometry and orientation of the articular surfaces, and the surface topography of the calcaneal corpus. Calcaneal morphology is unequivocal in its partitioning of quadrupedal pongids and bipedal hominids.