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1.
The type of climbing exhibited by apes and atelines is argued to have been important in the evolution of specialized locomotion, such as suspensory locomotion and bipedalism. However, little is known about the mechanics of climbing in primates. Previous work shows that Asian apes and atelines use larger joint excursions and longer strides than African apes and the Japanese macaque, respectively. This study expands knowledge of climbing mechanics by providing the first quantitative kinematic data for vertical climbing in four prosimian species: three lorisid species (Loris tardigradus, Nycticebus coucang, and Nycticebus pygmaeus) that share with apes and atelines morphological traits arguably related to climbing, and a more generalized quadruped, Cheirogaleus medius. Subjects were videotaped as they climbed up a wooden pole. Kinematic values, such as step length and limb excursions, were calculated and compared between species. The results of this study show that lorises, like Asian apes and spider monkeys, use relatively larger joint excursions and longer steps than does C. medius during climbing. These data lend further support to the idea that some primate species (e.g., lorises, atelines, and apes) are more specialized kinematically and morphologically for climbing than others. Pilot data suggest that such kinematic differences in climbing style across broad phylogenetic groups may relate to the energetics of climbing. Such data may be important for understanding the morphological and kinematic adaptations to climbing exhibited by some primates.  相似文献   

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The evolutionary relationships of extant great apes and humans have been largely resolved by molecular studies, yet morphology-based phylogenetic analyses continue to provide conflicting results. In order to further investigate this discrepancy we present bootstrap clade support of morphological data based on two quantitative datasets, one dataset consisting of linear measurements of the whole skull from 5 hominoid genera and the second dataset consisting of 3D landmark data from the temporal bone of 5 hominoid genera, including 11 sub-species. Using similar protocols for both datasets, we were able to 1) compare distance-based phylogenetic methods to cladistic parsimony of quantitative data converted into discrete character states, 2) vary outgroup choice to observe its effect on phylogenetic inference, and 3) analyse male and female data separately to observe the effect of sexual dimorphism on phylogenies. Phylogenetic analysis was sensitive to methodological decisions, particularly outgroup selection, where designation of Pongo as an outgroup and removal of Hylobates resulted in greater congruence with the proposed molecular phylogeny. The performance of distance-based methods also justifies their use in phylogenetic analysis of morphological data. It is clear from our analyses that hominoid phylogenetics ought not to be used as an example of conflict between the morphological and molecular, but as an example of how outgroup and methodological choices can affect the outcome of phylogenetic analysis.  相似文献   

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A broad range of variation in body size, brain size, and metabolic rate occurs within the primate family Lorisidae, thus providing an opportunity to examine the relationship of these three parameters to variation in growth and life history traits. Data on adult body weight, gestation length, lactation length, age at first estrus, litter size, and growth parameters were collected from a captive colony of four lorisid species, Loris tardigradus, Nycticebus coucang, Galago crassicaudatus, and G. senegalensis. The data presented here constitute the most complete life history information available for these poorly understood prosimian species. Correlation and allometric analyses were performed to determine the relationships between variables. Among the lorisids studied, adult body weight, adult cranial capacity, and relative cranial capacity did not predict variation in life history traits. Adult basal metabolic rate predicted most of the variability in gestation length, lactation length, and growth parameters. Lorisines differ from similarly sized galagines in having lower basal metabolic rates, slower growth rates, slower developmental rates, and smaller litter sizes, resulting in reduced reproductive potential. This may be a consequence of lorisine adaptation to a diet of toxic insects. Metabolic rate and diet may be among the most important parameters to examine in any study of life history evolution.  相似文献   

4.
中鲤亚属的分支系统学分析   总被引:2,自引:0,他引:2  
基于外部形态特征和内部骨骼特征对鲤科鲤属中鲤亚属进行了分支系统学分析,内群包括中鲤亚属的全部5种和鲤亚属的2种鱼类,外群采用乌原鲤。在鲤属鱼类和外群间共有48个性状存在变化。系统发育分析采用PAUP^*软件的Parsimony和Bootstrap两种方式的Branch-and-Bound算法,排除不能极化的特征和特有离征之后,还有28个特征可用,由这28个特征可得到唯一的系统树,树长69,一致性系数0.7246,排除无用特征的一致性系数0.6122,保留系数0.6346。由5种中鲤组成的中鲤亚属明显不构成一个单系群。结果表明:中鲤亚属是一个复系群,该类元应该被撤销。  相似文献   

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黄耆属簇毛黄耆亚属系统学研究   总被引:1,自引:0,他引:1  
簇毛黄耆亚属以其柱头上具簇毛等形态特征与黄耆属其它类群相区别,约含49种(变种)。主要分布在青藏高原及其邻近地区,绝大多数种类分布于横断山区。本文基于形态特征和分支系统学方法分析亚属内种系发生关系。结果表明,49种(变种)可分为9组。其中双小苞组Sect.Bibracteolati含种类最多,是一个并系类群。借助于分支图,分析了6个较重要的鉴定特征的演化,习性,茎的着生方式,小苞片,果实形态,柱头具簇毛,果实膨胀状况等。最后作出了这个亚属的一个分类纲要。  相似文献   

6.
The genus Myotis (Vespertilionidae, Myotinae) comprises a diverse group of small to large-sized vespertilionid bats that present a worldwide distribution. Twelve South American species are currently recognized. In this paper we evaluate the morphological and morphometric variation observed in South American populations of the most widespread species, Myotis nigricans. Against this background, two forms can be morphologically distinguished from M. nigricans and other known South American species. We describe these new species, documenting their diagnostic external and cranial characters by comparing them to other sympatric and cryptic species of South American Myotis. In addition, we provide an emended diagnosis of Myotis nigricans.  相似文献   

7.
Euryte koreana sp. nov. is described from the shallow littoral on the East Coast of South Korea, and represents the first record of the subfamily Euryteinae Monchenko, 1974 in the Pacific Ocean north of the tropics. It belongs to a group of species that have the caudal rami length/width ratio of around four, but differs from all congeners by a number of morphological features. Detailed drawings and extensive scanning electron micrographs of many characters of ornamentation provided for this species should serve as a benchmark for distinguishing closely related species in this subfamily with conservative macro-morphology. A morphologically distinct population from anchialine caves in Mallorca, identified previously as Euryte longicauda Philippi, 1843, is described as another new species: Euryte jaumei sp. nov. To test the phylogenetic relationships of its members and previous hypotheses about generic placement of two species associated with scleractinian corals, several cladistic analyses are performed on all 16 currently recognized species of Euryteinae and two outgroups, Neocyclops australiensis Karanovic, 2008 and Troglocyclops janstocki Rocha and Iliffe, 1994, using 25 morphological characters. All resulting trees suggest a close relationship between the two commensal species and them as a sister clade to all other Euryteinae. They are transferred into a newly erected genus Coraleuryte gen. nov., as C. bellatula (Humes, 1991) comb. nov. and C. verecunda (Humes, 1992) comb. nov., and a revised diagnoses is provided for the genus Euryte Philippi, 1843. Obtained cladograms also show that Ancheuryte Herbst, 1989 is nested deeply within the Euryte clade, so the genus is synonymized and its only species is transferred, as E. notabilis (Herbst, 1989) comb. nov. A key to species of Euryteinae is also provided.  相似文献   

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Primarily, 50 characters taken from herbarium specimens, cultivated plants, and whole populations ofPrimula veris L. were critically evaluated. Only 24 characters were found to be suitable for taxonomic use. The geographical and multivariate analysis of about 1000 herbarium specimens from the whole area lead to a reduction of the number of subspecies. Only a less restricted subsp.veris (incl. subsp.canescens, subsp.inflata and probably including subsp.macrocalyx) and subsp.columnae (incl. subsp.suaveolens) can be distinguished considering the variability of characters within an individuum, under different culture conditions, and during the growth period. The status of the taxon macrocalyx cannot be cleared presently.  相似文献   

12.
Taxa and homologues can in our view be construed both as kinds and as individuals. However, the conceptualization of taxa as natural kinds in the sense of homeostatic property cluster kinds has been criticized by some systematists, as it seems that even such kinds cannot evolve due to their being homeostatic. We reply by arguing that the treatment of transformational and taxic homologies, respectively, as dynamic and static aspects of the same homeostatic property cluster kind represents a good perspective for supporting the conceptualization of taxa as kinds. The focus on a phenomenon of homology based on causal processes (e.g., connectivity, activity-function, genetics, inheritance, and modularity) and implying relationship with modification yields a notion of natural kinds conforming to the phylogenetic-evolutionary framework. Nevertheless, homeostatic property cluster kinds in taxonomic and evolutionary practice must be rooted in the primacy of epistemological classification (homology as observational properties) over metaphysical generalization (series of transformation and common ancestry as unobservational processes). The perspective of individuating characters exclusively by historical-transformational independence instead of their developmental, structural, and functional independence fails to yield a sufficient practical interplay between theory and observation. Purely ontological and ostensional perspectives in evolution and phylogeny (e.g., an ideographic character concept and PhyloCode’s ‘individualism’ of clades) may be pragmatically contested in the case of urgent issues in biodiversity research, conservation, and systematics.  相似文献   

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Complete, articulated starfish fossils are rare. However, more frequently encountered dissociated skeletal elements (ossicles) permit reliable taxonomic identification, making them a valuable data source for diversity estimates. Nearly 300 asteroid ossicles, collected from the middle Toarcian marls in western France can be assigned to five species. Four species and two genera are described: Comptoniaster vrinensis nov. sp. (Goniasteridae), Poncetaster crateri nov. gen. nov. sp. (Stauranderasteridae), Galbaster recurrans nov. gen. nov. sp. (Goniasteridae) and Pentasteria? liasica nov. sp. (Astropectinidae). The known diversity of Early Jurassic asteroids is increased from 12 to 16 species. These taxa illustrate the diversification of crown-group asteroids early in the Jurassic, following the Permo-Triassic crisis. They also reflect bias of the fossil record, and imply the existence of numerous ghost lineages in the evolutionary trees of extant groups. Variation in asteroid diversity across the “Seuil du Poitou” was driven by ecological constraints. The relative frequency (abundance of ossicles and diversity) of goniasterids and stauranderasterids increases in shallower environments. The Benthopectinidae, represented by Plesiastropecten hallovensis, occurred primarily from deep-shelf sediments. Similar ecological patterns are observed for more recent fossil and extant relatives, which further supports the idea of conservative evolution in post-Palaeozoic starfishes since the Early Jurassic.  相似文献   

15.
Field data are presented from a 15-month study of spectral tarsiers in North Sulawesi, Indonesia, based on over 300 sightings of animals in the wild and supplemented by observations from other parts of the island. Animals in study area were caught in mist nets and marked with colored plastic bird rings so that tarsiers followed at night could be individually recognized. Ecological data presented cover the locomotion, use of forest strata, and diet of tarsiers. Although clearly specialized for vertical clinging and leaping, the spectral tarsier is less specialized than the western tarsier, occupying a wider range of habitats and using a wider range of vegetation strata and locomotor patterns. Diet is mostly insects collected both on the ground and in trees. Spectral tarsiers were found to be monogamous and territorial. Families regularly slept at the same sites each day and gave loud duet songs as they congregated at sleeping sites each dawn. Sometimes similar songs were given in the night during territorial conflicts. Family home ranges were plotted and average about 1 ha. Observations are included on mating, the development of young tarsiers, and the dispersion of juveniles. Tarsier young are very precocious and may travel independently as little as 23 days after birth. Tarsiers regularly scent marked their ranges by rubbing branches with urine and special epigastric glands. In addition, they have a varied repertoire of calls and the main vocalizations are described.  相似文献   

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Previous classification of the Disinae has been based almost entirely on floral morphological data. These data are critically assessed by various methods to determine to what extent they support a classification resolved to sectional level. The variation in the characters relative to the sections and genera is mapped, homologies are established by careful morphological observation and ontogenetic studies, and finally hypotheses of homology are tested by congruence in several cladistic analyseS. It is found that although floral morphology allows the recognition of some groups, for others the results are ambiguouS. Floral morphological data are clearly inadequate to establish the taxonomy of the Disinae on a sound footing.  相似文献   

19.
The quality of the fossil record and the accuracy of reconstructed phylogenies have been debated recently, and doubt has been cast on how far current knowledge actually reflects what happened in the past. A survey of 384 published cladograms of a variety of animals (echinoderms, fishes, tetrapods) shows that there is good agreement between phylogenetic (character) data and stratigraphic (age) data, based on a variety of comparative metrics. This congruence of conclusions from two essentially independent sources of data confirms that the majority of cladograms are broadly accurate and that the fossil record, incomplete as it is, gives a reasonably faithful documentation of the sequence of occurrence of organisms through time.  相似文献   

20.
We describe two new species of the nemesiid spider genus Chaco from Rocha Province, Uruguay. These new species are diagnosed based on genital morphology, male tibial apophysis spination, and burrow entrance. We test cospecificity of one species, Chaco costai,via laboratory mating experiments. The new species are diagnosed and illustrated and habitat characteristics, and capture behavior are described. We conduct a cladistic analysis based on a previously published morphological character matrix that now includes the newly described species.  相似文献   

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