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1.
The present study contrasts available biological data and results of morphofunctional analyses of the bill and hyoid apparatus in motmots. It shows that these omnivorous birds, which take relatively large food items, possess osteomuscular peculiarities that enable them to process these items as a whole in order to soften or cut them, and make them suited for easy ingestion. For that, they use the crenate edges of their rhamphotheca. Their jaws work as a highly mobile saw-like system. Their mutual movements, enhanced by the fact that particular dispositions of the hyoid apparatus rise the tongue and the supported items high up into buccal cavity, facilitate an effective clamping of items that can be moved along the jaws and be quite appropriately processed. 相似文献
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Misty L. Bastian 《American anthropologist》1999,101(1):201-202
Africa's Ogun: Old World and New. Second edition. Sandra T. Barnes. ed. Bloomington: Indiana University Press, 1997. 390 pp. 相似文献
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R. Danti G. Della Rocca B. Mori G. Torraca R. Calamassi M. Mariotti Lippi 《Plant Systematics and Evolution》2010,287(3-4):167-177
The aim of this work was to collect new information about pollen morphology and pollen wall structure comparing Cupressus species from the Old World and New World. Cupressus is a nonmonophyletic genus that includes species that appear to be divided into Old World and New World clades. Observations in this study on cypress pollen indicate that grain size and composition of intine β-glucans are different between the considered Old World and New World species. Different from all the other American cypress species, pollen of C. macrocarpa reacted to dying in a similar manner to Old World species. Rehydrated pollen grains collected from 20 Asian, Afro-Mediterranean and American cypress species were measured under a light microscope. The size of the pollen grains and the percentage of intine in relation to the pollen grain diameter were significantly different between Old World and New World species. Pollen wall composition was tested after addition of different dyes to the hydration solution, and subsequent observations were carried out by light and fluorescence microscopy. Lugol and calcofluor staining showed differences in composition of the middle and inner intine layers between New World and Old World species. 相似文献
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Iu K Eletski? R Z Saidova M I Shashirina 《Biulleten' eksperimental'no? biologii i meditsiny》1978,85(6):757-760
Histochemical study of the intramural nervous apparatus of the duodenum was carried out under normal conditions and following bilateral subphrenic vagotomy. Morphometric and microspectrofluorimetric methods gave informations on the reduction of the number of the cholinergic nervous fibers and of the acetylcholinesterase activity in them after a brief increase of these indices during the first 24 hours after vagotomy, with their subsequent return to the initial values. 相似文献
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I A Shevchuk N A Kovtuniak G M Iarmol'chuk N N Panchuk 《Arkhiv anatomii, gistologii i émbriologii》1977,73(12):68-72
Mature white male rats were used to study effects of hypophysectomy and STH on sugar content after fasting and after reiterated glucose loading. Morphological and morphometrical investigation of the pancreatic endocrine tissue were made. Zinc content and distribution in the pancreas, as well as aldehydefuchsinophil granulation in B-cells of the islets of Langergans were studied. Hypophysectomy was stated to increase functional activity of the pancreatic insular apparatus. Injection of STH for 9 days resulted in the stimulation of the cells in the insular apparatus. Prolonged injection of STH (for 20 days) produced exhaustion of the pancreatic insular apparatus. 相似文献
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J. S. Patterson C. J. Schofield J. P. Dujardin M. A. Miles 《Medical and veterinary entomology》2001,15(4):443-451
Quantitative analysis of morphological characters of the head was used to reconstruct the evolutionary history of the tropicopolitan bug Triatoma rubrofasciata (De Geer) (Hemiptera: Reduviidae) and seven species of Old World Triatoma. Multivariate analysis demonstrates that T. rubrofasciata and the Old World species have a high degree of similarity with Nearctic Triatoma species, particularly T. rubida (Uhler). We interpret this to imply a common ancestry for these groups. Dissemination of T. rubrofasciata and subsequent derivation of the Old World species of Triatoma is deduced to have occurred over a period of not more than 350 years. 相似文献
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Genotypic data from 39 microsatellite loci typed in 211 animals were used to assess the genetic differentiation between Old World and New World Holstein Friesian cattle populations. Gene diversities were similar in all five Holstein Friesian populations surveyed, ranging from 0.43 to 0.48. A tree of individuals based on the proportion of shared alleles indicated a clear distinction between Old World and New World Holstein Friesian populations. Similarly, genetic differentiation between populations, as measured by FST, was highly significant. Using the split decomposition method, we were able to visualize the significant introgression of New World Holstein Friesian into European Holstein Friesian populations. 相似文献
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Reinhardt V 《Journal of applied animal welfare science : JAAWS》2002,5(2):151-156
Permanent mother-infant separation prior to natural weaning is a common hus-bandry practice in monkey breeding colonies. In the United States, all eight Re-gional Primate Research Centers have such colonies. Under undisturbed conditions, Old World monkey mothers wean their infants at the age of about 1 year (Hall & DeVore, 1965; Poirier, 1970; Roonwal & Mohnot, 1977; Southwick, Beg, & Siddiqi, 1965). Natural weaning is a gradual process. It implies that the mother, over a period of several weeks or months, more and more consistently discourages her infant to suck on her breasts. Once the mother stops nursing the infant for good, the affectionate bond between the two is not broken (Altmann, Altmann, Hausfater, & McCuskey, 1977; Lindburg, 1971; Poirier, 1970; Roonwal & Mohnot, 1977). The young usually remains in the ma-ternal group at least until prepuberty. Under confinement conditions, artificial weaning is an abrupt occurrence that takes place several months prior to the biologically normal age of weaning. It im-plies that the still-nursed infant is taken away from the mother and subsequently reared alone or with other artificially weaned infants. 相似文献
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B N Bhattacharyya 《Gegenbaurs morphologisches Jahrbuch》1987,133(2):311-351
The study of the functional morphology of the feeding apparatus of some Indian insect-eating birds reveals suitable adaptational changes in the structure of their bill, skull-elements, tongue, and byoid in different degrees, depending on the nature of their partial adaptation to secondary food-habits. The hooked tip of the upper beak in Muscicapa and Dicrurus, sharp tomial edges of both the beaks in Turdoides and the long, gradually curved bill in Merops are some of the suitable adaptations of the bill for food-getting. The dimensional variations of the skull and its kinetic elements may be correlated not only with the food-habits of birds studied, but also with the patterns of jaw and tongue muscles possessed by them. A comparatively greater width of the cranium and height of the lower jaw in Turdoides and Dicrurus provide wider areas for the origins and insertions of the adductor muscles. The skull in all the birds studied is pro-kinetic. The kinesis of the upper jaw, however, depends on several factors of which the angles of placement of the quadrate-pterygoid-palatine components, the nature of the naso-frontal hinge and the resultant "torques" produced by differential forces of muscles are very significant. The upper jaw kinesis is best developed in Merops and Orthotomus. The variations in the structure of the tongue and hyoid may also be correlated with various movements of the tongue in both primary and secondary food-adaptations. 相似文献
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H. Herbert Cosman 《CMAJ》1996,155(4):422-423
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Eric N. Powell George M. Staff Robert J. Stanton Jr W. Russell Callender 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2001,34(2):97-118
We evaluate onshore-offshore trends in age-frequency distributions and trophic transfer efficiencies using 11 modern death assemblages off the Texas coast. Trophic transfer efficiencies within trophic levels offer little insight over that achieved by a size-frequency distribution. Production/biomass ratios will always be 1 in the fossil record. Within trophic-level estimates of paleogrowth efficiency, the ratio of paleoproduction to paleoingestion (Piglt/Iilt where i indicates the ith trophic level and lt indicates the time-averaged value) follow the expected ecological trend precisely in that paleogrowth efficiency is consistently higher in primary consumers than in predators in all 11 death assemblages. Paleoutilization efficiency, the ratio of predator paleoingestion to prey paleoproduction, I2lt°/P1glt°, may provide information on the degree of bias in the preservation of primary (1 °) and secondary (2 °) consumer trophic groups. I2lt°/P1glt° fell below 0.1 in most cold-seep and bay assemblages, indicating a large surplus of primary consumers. In sharp contrast, I2lt°/P1glt° 相似文献
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ADRIAN G. MARSHALL 《Biological journal of the Linnean Society. Linnean Society of London》1983,20(1):115-135
Old World phytophagous bats (Megachiroptera: Pteropodidae) number 173 species of which 79% are Asian and 21% African. Bats arose, presumably monophyletically, in the early Tertiary, the Megachiroptera soon diverging from the Microchiroptera. By the Cretaceous-Tertiary boundary the major groups of modern angiosperms were present, some of these probably being pollinated nocturnally by large insects and non-flying mammals and others with seeds dispersed by terrestrial vertebrates. Early bats were perhaps initially attracted to such flowers and fruit by the insects found around them, later finding the plants themselves nutritious. Megabats today feed upon floral resources, fruit and leaves from a total of at least 188 plant genera in 64 families. They may effect both pollination and seed-dispersal, and both bat-flower and bat-fruit syndromes are commonly recognized. Individual species are generally catholic in their feeding, favoured food varying with locality and season. Depending upon roosting habits and season, megabats may travel considerable distances each night to feed and may undertake seasonal migrations. Their feeding in orchards may sometimes require their control, but the future of certain species is more seriously threatened by slaughter for food and particularly by habitat destruction. 相似文献
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A. V. Zhuravlev 《Paleontological Journal》2007,41(5):549-557
Five functional types are recognized among Late Paleozoic conodont elements; they are distinguished by morphological and histological characteristics: grasping-holding, filtering, cutting, crushing, and grinding. Combinations of functional types of elements form functional types of conodont apparatuses, the main of which are filtering, grasping-cutting, grasping-pressing, grasping-cutting-grinding, and grasping-cutting-crushing apparatuses. 相似文献
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J. G. Dubouzet K. Shinoda 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1999,98(3-4):422-433
Phylogenetic analysis of ITS DNA sequences of various Old and New World Alliums suggests the reinclusion of Nectaroscordum and affirms the reestablishment of Caloscordum as subgenera of genus Allium. The results sanction the elimination of the Old World Allium species from subg. Amerallium Traub and endorse Wendelbo’s definition of subg. Molium (excluding sect. Porphyrason).
Received: 29 July 1998 / Accepted: 13 August 1998 相似文献
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From the Old World to the New World: a molecular chronicle of the phylogeny and biogeography of hystricognath rodents 总被引:2,自引:0,他引:2
The spider genus Hypochilus is currently restricted to cool, moist microhabitats in three widely separated montane regions of North America, providing an opportunity to study both deep (i.e., continental level) and shallow (within montane region) biogeographic history. Members of the genus also retain many plesiomorphic morphological characteristics, inviting the study of comparative rates of morphological evolution. In this paper, Hypochilus phylogeny and associated evolutionary problems are addressed using both new molecular (28S nDNA and CO1 mtDNA) and previously published (K. M. Catley, 1994, Am. Mus. Nov. 3088, 1-27) morphological data. Although the molecular data provide limited resolution of root placement within Hypochilus, most analyses are at least consistent with morphology-supported montane relationships of (Rockies (California, Appalachian)). The monophyly of Hypochilus species distributed in the California mountains is ambiguous, with several analyses indicating that this fauna may be paraphyletic with respect to a monophyletic Appalachian lineage. The montane regions differ in consistent ways in depths of both mitochondrial and nuclear phylogenetic divergence. Molecular clock analyses, in combination with arthropod-based mtDNA rate calibrations, suggest that the regional faunas are of different ages and that speciation in all faunas likely occurred prior to the Pleistocene. Limited intraspecific sampling reveals extraordinarily high levels of mtDNA cytochrome oxidase sequence divergence. These extreme divergences are most consistent with morphological stasis at the species level, despite preliminary evidence that Hypochilus taxa are characterized by fragmented population structures. 相似文献
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Pomak Portraits: The Women of Breznitsa (43 minutes) and Old Ibrahim's World (41 minutes"). Two Videos by Asen Balikei. produced 1994. released 1997. For more information contact Institut fuür den Wissenschaftliche Film. Postfach 235 I. D-37013. Göttingen. Germany (tel 0551/5024-0: fax 0551/5024-400). 相似文献
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The relationship between body size and feeding ecology is well established for primates. It is argued that the evolutionary history of modern New World monkeys and, in particular, the path to attainment of current body size is significant in understanding the similarities and differences between dietary strategies and other ecological parameters of similar-sized monkeys. Current interpretations of New World monkey evolutionary relationships are reviewed. Based on a synthesis of available body weights and the assumption that the earliest New World monkeys weighed close to 1 kg, similar to modern Aotus and Callicebus, predicted patterns of body size change in each lineage are given. Restrictions on directions of body size change in primates are discussed, and it is shown that "Stanley's Rule" offers a good explanation for differing body size ranges in New and Old World anthropoids. Predicted ecological correlates to body size drawn from the mammalian literature are offered and tested using data on New World monkeys, which show some concurrence and several interesting departures from predicted patterns. Sexual dimorphism in body weight of New World monkey species is reviewed, based on the new summary of body weight data given. 相似文献