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1.
This paper analyzes nonmetric trait variation in 11 late Late Woodland (ca. AD 700-1000) and one Mississippian (AD 1000-1300) skeletal samples from west-central Illinois from a population-structure perspective. Most of the sites are of the Bluff phase of Late Woodland in the lower Illinois River valley; others are from a nearby, contemporary archaeological phase. Late Woodland as a whole era (ca. AD 250-1000) was a period of marked population growth and expansion into new regional environments, trends that accompanied horticultural intensification in the area. Overall variation between sites was low, but males, females, and the total sample exhibited a significant geographic component to variation due to interregional morphological differences. The Bluff sites tended to group together relative to the non-Bluff sites. However, there was no significant geographic component to variation among the Bluff sites. The results are only partially consistent with archaeological data suggesting population growth and expansion through fissioning. Previous studies have demonstrated significant heterogeneity for nonmetric trait frequencies among Middle Woodland (ca. 100 BC to AD 250) sites, suggesting a Middle to Late Woodland change in population structure that lowered levels of morphological variation. This supports a model of increased intra- and interregional interaction from Middle to Late Woodland times developed from ceramic data by Braun and by Braun and Plog.  相似文献   

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The larynges (except for the epiglottis) of two adult Mongolian gazelles, one male and one female, were dissected. This species is characterized by a pronounced sexual dimorphism of the larynx. Dimorphism with regard to the size of the entire larynx and of the thyroid cartilage is about 2:1 whereas the difference of mean body mass is about 1.3:1 between males and females. Unexpectedly, and in contrast to other bovids, the larynx of the male Mongolian gazelle has a paired lateral laryngeal ventricle. However, in contrast to horse, dog, pig and many primate species also possessing such a paired ventricle, its rostral opening in the Mongolian gazelle is situated lateral to the corniculate process of the arytenoid cartilage. The neck of the laryngeal ventricle is embraced by the bifurcated cuneiform process of the epiglottis. Despite the enlarged laryngeal cartilages, the vocal process of the male arytenoid cartilage is relatively shorter than that of the female. The male thyroarytenoid muscle is clearly separated into a rostral ventricular muscle and a caudal vocal muscle whereas the female's, as in other bovids, is almost uniform. The lateral sac of the two-chambered laryngeal ventricle in the male projects laterally between the ventricular and the vocal muscle. As in the domestic bovids and in many other artiodactyls the larynx of the male Mongolian gazelle is lacking any rostrally directed membraneous portion of the vocal fold. Instead, the thick and tough bow-like vocal fold projects caudally into the infraglottic cavity and is supported by a peculiar pan-like fibroelastic pad. This resilient element, situated medial to the bipartite thyroarytenoid muscle, might be a homologue of the vocal ligament, eventually including lateral portions of the elastic cone. A fibroelastic pad is absent in the female. The resilient floor of the laryngeal vestibulum, ventral to the fibroelastic pad, is rostrally and caudally subducted by tube-like spaces. Evolutionary enlargement of the male larynx, including the vocal folds, and of the caudal portions of the vocal tract may have shifted the fundamental and formant frequencies to a lower register. The paired lateral laryngeal ventricle might produce an amplitude increase of the vocalizations assisted by differential action of the bipartite thyroarytenoid muscle. In addition, the peculiar shape, size and tough consistency of the male vocal folds may, as in roaring felids, assist in producing high amplitude and low frequency vocalizations. Perhaps the biological role of the enlarged male larynx of Procapra gutturosa has evolved in relation to its mating system. In the rutting season, dominant males establish individual territories and maintain harems. During prolonged courtship prior to mating, these males perform an acoustic display uttering loud and guttural bellows. In addition, the bulging ventral neck region of males may serve as an optical attractant for the females. Thus, the evolution of the enlarged larynx of the male Mongolian gazelle may have been favoured by sexual selection.  相似文献   

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石蒜属12种植物叶片比较解剖学研究   总被引:2,自引:0,他引:2  
对石蒜属(Lycoris Herb.)12种植物叶片的比较解剖学研究表明:(1)石蒜属植物叶片横切面的端部、中部及基部的轮廓基本呈浅“W”或“V”字型,有些种的表皮细胞上具有明显的尖刺状乳突;(2)石蒜属植物均为异面叶,叶肉组织有一定的栅栏组织和海绵组织分化,但二者的厚度、叶肉中所占比例及栅栏组织的细胞层数在种间有一定的差异;(3)海绵组织发达、具有大而明显的薄壁细胞或细胞裂溶后形成空腔(分泌腔或气腔);(4)叶片中维管束数目大多为奇数,叶脉维管束鞘由薄壁细胞组成;(5)石蒜属植物横切面上叶缘的形状分为圆弧形和楔形两种类型。石蒜属植物叶的解剖结构具有许多相似特征;同时又具有一定的种间差异,可为石蒜属槽物的种间关系和开发利用提供有价值的信息。  相似文献   

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暗罗属植物叶的比较解剖学研究   总被引:6,自引:0,他引:6  
利用扫描电镜技术、叶片叶片离析方法和石蜡切片法对暗罗属12种植物叶和形态结构进行了比较研究。结果表明,叶表皮细胞形状、气孔器形态、表皮毛类型、表皮细胞中晶体类型、叶肉中油细胞分布位置、栅栏组织和海绵组织厚度的比值,以及主脉维管组织的结构特征等具有明显的种间差异。可以利用这些叶的解剖特征将暗罗属植物相互区别开来。  相似文献   

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赤爮亚族植物营养器官的比较解剖   总被引:2,自引:1,他引:1  
对赤Bo亚族3属共12种植物的营养器官进行了比较解剖学研究,其结果是:1在卷须的解剖结构上,赤Bo属和白兼果属有是显的区别。前者具周维管纤维。但其维管束发育差;后者不具周维管纤维,但其维管束发育良好。从系统演化上来说,完善的维管系统显然比周维管纤维有更强的机械功能。2.草酸钙盐的结晶体,硅质细胞和钟乳体分别存在于白兼果属,罗汉果属和苦瓜属植物中,而在赤Bo属植物中未发现上述结构物质。3.比较解剖学  相似文献   

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对赤 亚族3属共12种植物的营养器官进行了比较解剖学研究,其结果是:1.在卷须的解剖结构上,赤 属和白兼果属有明显的区别。前者具周维管纤维,但其维管束发育很差;后者不具周维管纤维,但其维管束发育良好。从系统演化上来说,完善的维管系统显然比周维管纤维有更强的机械功能。2.草酸钙盐的结晶体、硅质细胞和钟乳体分别存在于白兼果属、罗汉果属和苦瓜属植物中,而在赤 属植物中未发现上述结构物质。3.比较解剖学的证据部分地支持了赤属和白兼果属的近缘关系以及赤 属是赤 亚族中相对原始的分类群的观点。  相似文献   

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Leaf anatomy of six genera was investigated. The petiole of Brasenia schreberi possesses a pair of bundles, the other five possess closed, scattered vascular bundles, resembling those of the Monocotyledons. True vessels are absent. Air passages are present in the ground tissue of the petiole except for Nuphar pumilum. Leaves are all dorsiventral. Stomatal apparatuses of the Ranunculaceous type are generally confined to the upper surface of the lamina, but fewer stomata are found on the lower surface of the lamina of Nelumbo nucifera. The stomatal apparatuses of Nelumbo nucifera are of the Haplocheilic type in development, but of the Ranunculaceous type at maturity. Hydathodes and sclerenchymatous idioblasts are present only in Nelumbo nucifera. Glandular hairs and hydropotens occur on the lower surface of the lamina in all the investigated species except Nelumbo nucifera. Astrosclereids are present in all the taxa except Brasenia schreberi and Nelumbo nucifera. According to observations we consider that the genus Brasenia is a primitive one in Nymphaeaceae and it has a close phylogenetic relationship with Cabomba. They may be treated as an independent family, Cabombaceae, which is better included in the order Nymphaeales. Nymphaea, Nuphar, Euryale and Victoria are closely related to one another and should be retained in the family Nymphaeaceae. Nelumbo shows, specialized features distinct from those of the rest of the Nymphaeaceae. It should be segregatednot only as a distinct family but also as a distinct order, Nelumboales.  相似文献   

9.
The frequency and form of the middle trigonid crest (MTC) in lower permanent molars is reported for 1,131 dental casts of Bushman (San), Bantu, Solomons, Hawaiians, Pima, Eskimo, Navajo, Chinese, and American whites. The MTC occurs most often on the first molar. We found very little intra-trait variation, so observations were scored on a present-absent basis. The MTC is most frequent in the African samples and rare in those of the other populations. Two reference plaques can be obtained to add to the existing series in the ASU dental anthropology system. © 1993 Wiley-Liss, Inc.  相似文献   

10.
利用扫描电镜技术,叶片离析方法和石蜡切片法对蚁花属1种和澄广花属9种植物叶的形态结构进行比较研究。结果表明,两属植物有许多相似之处,但又有以下一些显著不同;蚁花属植物叶表皮细胞均具一晶族,叶肉组织中具1-2层栅栏组织细胞,油细胞均匀分布在栅栏组织和海绵组织中,栅栏组织在主脉处不连续,而澄广花属植物叶的表皮细胞内具一单斜晶,叶肉组织中具1层栅栏组织细胞,油细胞仅分布在海绵组织中,栅栏组织在主脉处连续,结果为蚁花属和澄广花属的分类学处理提供了新证据。  相似文献   

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Chondrocranial morphology of leptodactylid frogs is scarcely known and has not been completely described for any species of Leptodactylus. We describe the diversity of chondrocranial morphology in the genus Leptodactylus based on the analysis of 22 species, representing the four species groups: the fuscus Group, ocellatus Group, melanonotus Group, and pentadactylus Group. Furthermore, 26 characters are identified and used in a phylogenetic analysis. The phylogenetic analysis using Physalaemus, Crossodactylus, and Hylodes as outgroups suggests two monophyletic clades within Leptodactylus: the melanonotus-ocellatus clade and the pentadactylus-fuscus clade. However, it does not support the monophyly of the species groups as currently recognized and it suggests a paraphyletic Leptodactylus. Enforcing the monophyly of the ingroup, i.e., Leptodactylus, results in the same major two clades of Leptodactylus. Leptodactylus riveroi, a taxon previously unassigned to any species group, appears most closely related to the melanonotus-ocellatus clade based on chondrocranial characteristics. J. Morphol. 238:287–305, 1998. © 1998 Wiley-Liss, Inc.  相似文献   

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The absence of a midtarsal break has long been regarded as a derived feature of the human foot. Humans possess a rigid midfoot that acts as an efficient lever during the propulsive phase of bipedal gait. Non‐human primates, in contrast, have a more mobile midfoot that is adaptive for tree climbing. Here, we report plantar pressure and video evidence that a small percentage of modern humans (n = 32/398) possess both elevated lateral midfoot pressures and even exhibit midfoot dorsiflexion characteristic of a midtarsal break. Those humans with a midtarsal break had on average a significantly flatter foot than those without. Midtarsal breakers also had significantly more medial weight transfer (pronation) during the stance phase of gait than those without this midfoot mobility. These data are in accordance with Elftman (Clin Orthop 16 (1960) 41–45) who suggested that pronation aligns the axes of the transverse tarsal joint, permitting elevated midfoot mobility. Am J Phys Anthropol 151:495–499, 2013.© 2013 Wiley Periodicals, Inc.  相似文献   

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The aim of this study was to ascertain the distribution in primates of the three possible bony ponticles over the groove for the vertebral artery (ventral, lateral, and dorsal ponticles), in order to attempt to understand the variants observed in humans and to ascertain possible evolutionary trends in primates. The material consisted of 393 atlases of extant nonhuman primates representative of 41 genera, and of 500 human atlases (dried bones of adults). For each atlas, we studied the existence and morphology of the ponticles, and the type of association of these three ponticles on a given side, which are theoretically of eight in number (types A-H). The occurrence of these ponticles varied from complete absence to constant presence, according to the genera and taxa of primates. The presence of each of these ponticles in primates can be interpreted as a primitive or plesiomorphic character, and their absence as a derived or apomorphic character. The strepsirhines-platyrrhines-cercopithecines group, presenting a predominant primitive pattern (type A), appeared to be separated from the colobines-hominoids group, presenting predominant derived patterns (type C in colobines, Pongo pygmaeus, and Pan troglodytes, and the more derived type D in Hylobates, Gorilla gorilla, and Homo sapiens). The last derived stage, corresponding to the disappearance of the three atlantal ponticles (type H), was only observed in some individuals in hominoids. A marked intraspecific polymorphism characterized the hominoids. The presence of lateral and dorsal ponticles in humans appeared to correspond to their persistence within the progressive disappearance of the atlantal ponticles, constituting an evolutionary tendency characteristic of primates and particularly of hominoid evolution.  相似文献   

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Patterns of ectocranial suture fusion among Primates are subject to species‐specific variation. In this study, we used Guttman Scaling to compare modal progression of ectocranial suture fusion among Hominidae (Homo, Pan, Gorilla, and Pongo), Hylobates, and Cercopithecidae (Macaca and Papio) groups. Our hypothesis is that suture fusion patterns should reflect their evolutionary relationship. For the lateral‐anterior suture sites there appear to be three major patterns of fusion, one shared by Homo‐Pan‐Gorilla, anterior to posterior; one shared by Pongo and Hylobates, superior to inferior; and one shared by Cercopithecidae, posterior to anterior. For the vault suture pattern, the Hominidae groups reflect the known phylogeny. The data for Hylobates and Cercopithecidae groups is less clear. The vault suture site termination pattern of Papio is similar to that reported for Gorilla and Pongo. Thus, it may be that some suture sites are under larger genetic influence for patterns of fusion, while others are influenced by environmental/biomechanic influences. J. Morphol. 275:342–347, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   

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The debate over the taxonomic position and affinities of Trachypithecus auratus has been ongoing since its identification by E. Geoffroy Saint-Hilaire in 1812. The type specimen of this species is housed in Muséum national d'Histoire naturelle in Paris (MNHN-ZM 2005-912). This point is debated due to the complex and fluctuating taxonomy of Southeast Asian Colobinae (Brandon-Jones et al.: Int J Primatol 25 (2004) 97-164) and to the fact that this individual is represented by a mounted skeleton. By means of 3D medical imaging methodologies we describe for the first time the cranial anatomy of the specimen MNHN-ZM 2005-912 and compare it with other Trachypithecus species, in order to test the molecular systematic hypotheses for affinities among the T. auratus-T. cristatus group. We ascertain the taxonomic attribution of this individual to the species Trachypithecus auratus species. The most diagnostic characters shared by the type specimen and Trachypithecus auratus compared to other species of Trachypithecus are the rounded orbits and the straight facial profile. We then try to clarify the inconsistencies concerning the geographical provenance of the type. The island of Java appears to be the most probable locality from a cluster analysis based on linear morphometry. After this approach and a discriminant analysis, a northeastern Javanese provenance of this specimen, as proposed by Brandon-Jones et al. (Int J Primatol 25 (2004) 97-164) is dubious. Finally we provide 3D models of the skull and the endocast, and a list of cranial landmark coordinates of the holotype for future research.  相似文献   

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Glutamic-pyruvic transaminase (GPT) in red cells of 25 species of non-human primates was investigated. There were significant differences in red cell GPT activities among species. Some species in the Prosimiae and the Ceboidea have high red cell GPT activities, while the others of these families examined have low activities. In contrast, red cell GPT activities were too low to be detected in the Cercopithecoidea and the Pongidea. The intraspecific variation of GPT zymograms was observed in Aotes trivirgatus by starch gel electrophoresis.  相似文献   

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