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61.
Morphological divergence was evident among three sympatric morphs of Arctic charr (Salvelinus alpinus (L.)) that are ecologically diverged along the shallow‐, deep‐water resource axis in a subarctic postglacial lake (Norway). The two deep‐water (profundal) spawning morphs, a benthivore (PB‐morph) and a piscivore (PP‐morph), have evolved under identical abiotic conditions with constant low light and temperature levels in their deep‐water habitat, and were morphologically most similar. However, they differed in important head traits (e.g., eye and mouth size) related to their different diet specializations. The small‐sized PB‐morph had a paedomorphic appearance with a blunt head shape, large eyes, and a deep body shape adapted to their profundal lifestyle feeding on submerged benthos from soft, deep‐water sediments. The PP‐morph had a robust head, large mouth with numerous teeth, and an elongated body shape strongly related to their piscivorous behavior. The littoral spawning omnivore morph (LO‐morph) predominantly utilizes the shallow benthic–pelagic habitat and food resources. Compared to the deep‐water morphs, the LO‐morph had smaller head relative to body size. The LO‐morph exhibited traits typical for both shallow‐water benthic feeding (e.g., large body depths and small eyes) and planktivorous feeding in the pelagic habitat (e.g., streamlined body shape and small mouth). The development of morphological differences within the same deep‐water habitat for the PB‐ and PP‐morphs highlights the potential of biotic factors and ecological interactions to promote further divergence in the evolution of polymorphism in a tentative incipient speciation process. The diversity of deep‐water charr in this study represents a novelty in the Arctic charr polymorphism as a truly deep‐water piscivore morph has to our knowledge not been described elsewhere.  相似文献   
62.
Neanderthal forearms have been described as being very powerful. Different individual features in the lower arm bones have been described to distinguish Neanderthals from modern humans. In this study, the overall morphology of the radius and ulna is considered, and morphological differences among Neanderthals, Upper Paleolithic Homo sapiens and recent H. sapiens are described.Comparisons among populations were made using a combination of 3D geometric morphometrics and standard multivariate methods. Comparative material included all available complete radii and ulnae from Neanderthals, early H. sapiens and archaeological and recent human populations, representing a wide geographical and lifestyle range.There are few differences among the populations when features are considered individually. Neanderthals and early H. sapiens fell within the range of modern human variation. When the suite of measurements and shapes were analyzed, differences and similarities became apparent. The Neanderthal radius is more laterally curved, has a more medially placed radial tuberosity, a longer radial neck, a more antero-posteriorly ovoid head and a well-developed proximal interosseous crest. The Neanderthal ulna has a more anterior facing trochlear notch, a lower M. brachialis insertion, larger relative mid-shaft size and a more medio-lateral and antero-posterior sinusoidal shaft. The Neanderthal lower arm morphology reflects a strong cold-adapted short forearm. The forearms of H. sapiens are less powerful in pronation and supination. Many differences between Neanderthals and H. sapiens can be explained as a secondary consequence of the hyper-polar body proportions of the Neanderthals, but also as retentions of the primitive condition of other hominoids.  相似文献   
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The kipunji, a recently discovered primate endemic to Tanzania's Southern Highlands and Udzungwa Mountains, was initially referred to the mangabey genus Lophocebus (Cercopithecinae: Papionini), but subsequent molecular analyses showed it to be more closely related to Papio. Its consequent referral to a new genus, Rungwecebus, has met with skepticism among papionin researchers, who have questioned both the robustness of the phylogenetic results and the kipunji's morphological distinctiveness. This circumstance has been exacerbated by the immaturity of the single available specimen (FMNH 187122), an M1-stage juvenile. Therefore, a geometric morphometric analysis of juvenile papionin cranial shape was used to explore the kipunji's phenetic affinities and evaluate morphological support for its separation from Lophocebus. Three-dimensional craniometric landmarks and semi-landmarks were collected on a sample of 124 subadult (dp4-M2 stage) cercopithecid crania. Traditional interlandmark distances were compared and a variety of multivariate statistical shape analyses were performed for the zygomaxillary region (diagnostic in mangabeys) and the cranium as a whole. Raw and size-adjusted interlandmark distances show the kipunji to have a relatively taller, shorter neurocranium and broader face and cranial base than is seen in M1-stage Lophocebus. Principal components and cluster analyses consistently unite the two Lophocebus species but group the kipunji with Cercocebus and/or Macaca. Morphological distances (Mahalanobis D2) between the kipunji and Lophocebus species are comparable to distances between recognized papionin genera. Discriminant function analyses suggest phenetic affinities between the kipunji and Cercocebus/Macaca and do not support the kipunji's classification to Lophocebus or to any other papionin taxon. In canonical plots, the kipunji occupies a region intermediate between macaques and African papionins or groups with Cercocebus, suggesting that it retains basal papionin shape characteristics. In shape comparisons among M1-stage papionins, the kipunji cranium is distinguished from Lophocebus by its relatively unrestricted suborbital fossa, more parasagittally oriented zygomatic arches, and longer auditory tube and from all papionins by its relatively tall, short neurocranium, broad face and cranial base, short nasals, dished nasal profile, and dorsally oriented rostrum. The kipunji is thus a cranially diagnosable phenon with a unique combination of cranial traits that cannot be accommodated within Lophocebus as currently defined. Based upon these results, Rungwecebus appears to be a valid and useful nomen that accurately reflects the morphological diversity of African papionins.  相似文献   
66.
The taxonomic uncertainty surrounding cryptic species complexes has traditionally been resolved using lengthy experimental approaches, while, since the advent of PCR based techniques the number of cryptic species described in a variety of taxa is increasing steadily. Here we formally describe a new rotifer species of the Brachionus plicatilis complex: Brachionus manjavacas n.sp., disentangling what was known as a morphological stasis. Detailed morphological analyses demonstrated significant differences in body shape and size between B. manjavacas and B. plicatilis s.s., analysed by geometric morphometrics; unfortunately these statistical differences are not taxonomically reliable because of wide overlaps. Size and asymmetry of masticatory apparatus, named trophi, observed by SEM, gave similar results, with taxonomic ambiguity. Only the shape of small pieces of the trophi, named satellites, were consistently different between the species. On a strictly classical taxonomical basis it is absolutely useful to name new species on morphological bases, as we did, and to assess their status as distinct entities. Nevertheless, the two species are broadly similar; therefore, we do not suggest using the small differences in shape of satellites of trophi to identify the species for further ecological studies, but to continue discriminating them on genetic marker bases. Handling editor: K. Martens  相似文献   
67.
本文研究了两种鲤科鱼类,即分布于华南长江与西江的宽鳍雠和马口鱼的不同线粒体DNA谱系之间的体形差异。近期基于线粒体DNA的这两个物种的系统发育分析认为这两个类元内包含多个谱系(宽鳍鱲A—D和马口鱼1—5)。本文采用几何形态度量学的方法研究了这些不同线粒体DNA谱系间是否存在体形方面的差异。在宽鳍馘的4个不同的线粒体DNA谱系中,有3个被纳入本研究内容。结果显示:在宽鳍雠的3个线粒体DNA谱系中,2个具有体形的差异。在马口鱼的5个线粒体DNA谱系中,3个被纳入本文的研究。结果显示所有3个谱系均存在体形差异。因此,线粒体DNA的谱系差异很大程度上表现在谱系间的体形差异方面,表明线粒体DNA谱系可能对应于不同的物种。  相似文献   
68.
采用长时间连续采样的方法研究了黄脸油葫芦Teleogryllus emma(Ohmachi et Matsumura)、北京油葫芦Teleogryllus mitratus(Burmeister)和黑脸油葫芦Teleogryllus occipitalis(Serville)等3种油葫芦的鸣声节律特征谱图,分析其特点及其在鸣声分类中的意义.  相似文献   
69.
通过对兰州生物制品研究所试生产的流行性感冒灭活疫苗的体试验研究,兰州所流感灭活疫苗接种后,所有接种对象均未见红肿,硬结等局部反应,仅有1例发生在儿童组的低热全身反应(体温37.4℃),72小时后恢复正常,整体副反应发生率0.274%,肯定了该疫苗的安全性,疫苗接种前后易人群血清血凝抑制(HI)抗体阳转率100%,非易感人群HI抗体几何平均效价(GMT)增长19-60倍,抗体4倍增长率最低为95%,成人组平均值最高(97.67%),证实该疫苗具有较好的免疫原性。  相似文献   
70.
The brown rat, Rattus norvegicus, is a model system in ecological and systematic science, but little is known about its skull morphology and developmental patterns. Our objective was to investigate the cranial ontogenetic patterns in the brown rats, from Hai’l, Kingdom of Saudi Arabia.Quantitative analysis of sexual shape dimorphisms (SShD) and age-classes were investigated using 28 landmarks plotted on two-dimensional images for dorsal and ventral views. Our results detected statistically significant sexual dimorphism (P-value <0.0001) in cranial shape and size for R. norvegicus. Nevertheless, males are much larger than females and display variation around the brain-case, while females tend to show greater variation around the occipital bone. In addition, there are subtle age-classes during ontogeny in the skull. However, the older age classes (i.e. age classes 3 and 4) represent well-built crania with an extended case of the brain and shortest nasal, while youngest specimens represent an elongated snout of minimum crania.Future GMM research should therefore examine the pre-defined age-classes and sex-related individuals in brown rat skulls in relation to genotype to characterize trends in skull shape variation that may affect teeth, zygomatic arches, brain case, and compartments of muscle attachments through its ecological patterns.  相似文献   
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