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Developmental dental pathologies provide insight into health of primates during ontogeny, and are particularly useful for elucidating the environment in which extant and extinct primates matured. Our aim is to evaluate whether the prevalence of an unusual dental defect on the mesiolabial enamel of the upper lateral incisor, thought to reflect dental crowding during maturation, is lesser in female orangutans, with their smaller teeth, than in males; and in Sumatran orangutans, from more optimal developmental habitats, than in those from Borneo. Our sample includes 49 Pongo pygmaeus (87 teeth), 21 P. abelii (38 teeth), Late Pleistocene paleo-orangutans from Sumatra and Vietnam (67 teeth), Late Miocene catarrhines Lufengpithecus lufengensis (2 teeth), and Anapithecus hernyaki (7 teeth). Methods include micro-CT scans, radiography, and dental metrics of anterior teeth. We observed fenestration between incisor crypts and marked crowding of unerupted crowns, which could allow tooth-to-tooth contact. Tooth size does not differ significantly in animals with or without the defect, implicating undergrowth of the jaw as the proximate cause of dental crowding and defect presence. Male orangutans from both islands show more defects than do females. The defect is significantly more common in Bornean orangutans (71 %) compared to Sumatran (29 %). Prevalence among fossil forms falls between these extremes, except that all five individual Anapithecus show one or both incisors with the defect. We conclude that maxillary lateral incisor defect is a common developmental pathology of apes that is minimized in optimal habitats and that such evidence can be used to infer habitat quality in extant and fossil apes.  相似文献   

3.
The first skull of a rhinoceros of the genus Stephanorhinus has been found above the Arctic Circle on the middle Chondon River (Yakutia, Russia). This is the northernmost finding that extends significantly the genus range and provides additional information about the diet and environment of a genus representative. Plant remnants from the maxillary tooth cavities were identified as belonging to trees (Larix, Betula), shrubs (Ericaceae), mosses (Aulacomnium sp., Polytrichum sp.), herbs (Dicotyledones) and grasses (Poaceae), but not to sedges (Cyperaceae). The pattern of attrition of teeth and marks on the chewing surface enamel indicate diverse nourishment. Chondon rhinoceros lived in under Arctic-like climatic conditions, with rather limited food resources.  相似文献   

4.
From the Bavarian Early/Middle Miocene (MN5) site Sandelzhausen, nine species of carnivoran mammals are identified including the hemicyonine ursid Hemicyon stehlini, the amphicyonids Amphicyon cf. major and Pseudarctos bavaricus, the mustelids Ischyrictis zibethoides and Martes cf. munki, the mephitid Proputorius pusillus, the viverrid Leptoplesictis cf. aurelianensis, the felid Pseudaelurus romieviensis, and finally the recently described barbourofelid Prosansanosmilus eggeri. With these taxa present, Sandelzhausen shows a carnivoran community typical, though deprived, for the Lower to Middle Miocene of Europe, but different from roughly contemporary Mediterranean faunas such as those from Çandir or Pa?alar in Turkey.  相似文献   

5.
The dentition of Cambaytherium was investigated in terms of dental wear, tooth replacement and enamel microstructure. The postcanine tooth row shows a significant wear gradient, with flattened premolars and anterior molars at a time when the last molars are only little worn. This wear gradient, which is more intensive in Cambaytherium thewissi than in Cambaytherium gracilis, and the resulting flattened occlusal surfaces, may indicate a preference for a durophagous diet. The tooth replacement (known only in C. thewissi) shows an early eruption of the permanent premolars. They are in function before the third molars are fully erupted. During the dominant phase I of the chewing cycle the jaw movement is very steep, almost orthal, with a slight mesiolingual direction and changes into a horizontal movement during phase II. The enamel microstructure shows Hunter-Schreger-bands (HSB) in the inner zone of the enamel. In some teeth the transverse orientation of the HSB is modified into a zig-zag pattern, possibly an additional indicator of a durophagous diet.  相似文献   

6.
Brasenia Schreb. is a monotypic genus in the Cabombaceae, present nowadays on all continents except Europe and Antarctica. This thermophilous aquatic plant, which originated in the Tertiary, was a frequent element of aquatic plant life during the interglacial stages of the European Pleistocene. A systematic review of the palaeobotanical records of Brasenia pollen and seeds reveals its history in Europe from the Plio-Peistocene until the Eemian interglacial. Remains of Brasenia were typical for the climatic optima during each of these stages of the Pleistocene. In this paper the diversity of fossil Brasenia species is also shown. The most abundant and morphologically diverse seeds were found in sediments from eastern European sites. Brasenia species became extinct in Europe at the end of the last interglacial or at the beginning of the Weichselian glaciation. Different scenarios for their disappearance are proposed, including the specificity of the floral cycle, probable poor dispersal of seeds, or the scarcity of suitable water bodies for it to survive.  相似文献   

7.
Within the fossil collection from the Sandelzhausen Lagerstätte in the Upper Freshwater Molasse near Mainburg, Germany, are remains of the schizotheriine chalicothere Metaschizotherium bavaricum, von Koenigswald, 1932. This new material includes elements from a large part of the body, and allows the dentition and postcranial skeleton of Metaschizotherium to be described in detail for the first time. At approximately 16 Ma (MN5), M. bavaricum is now the best-known Early and Middle Miocene European schizotheriine and is important for comparative studies. It differs to some degree from earlier Miocene (MN2–MN4) European material attributed to Moropus sp. or Metaschizotherium wetzleri (Kowalewsky, 1873) and to a larger degree from the Late Miocene species Ancylotherium pentelicum (Gaudry and Lartet, 1856). At Sandelzhausen, M. bavaricum apparently lived in a moist forested environment, where it probably fed on leaves, fruit, and seeds. Members of the Chalicotheriinae, such as Anisodon and Chalicotherium, are not found at Sandelzhausen and may not have been present in Europe at this time. M. bavaricum, like other Schizotheriinae, did not have the bizarre gorilla-like proportions of the Chalicotheriinae. Instead, its general body proportions resemble those of contemporary schizotheriine chalicotheres on other continents, for example, Moropus from North America. M. bavaricum is slightly smaller than the type species of Metaschizotherium, M. fraasi von Koenigswald, 1932 (MN6–MN7) and differs from it in small ways that are still being explored as variation within and differences between these species are clarified. The schizotheriine chalicothere from La Grive St.-Alban (France) referred to M. fraasi by von Koenigswald (Palaeontographica, Beitrage zur Naturgeschichte der Vorzeit 8:1–24, 1932) and Viret (Nouvelles Archives Musée d’Histoire Naturelle de Lyon 6:53–81, 1961) should be restudied and referred to a different taxon.  相似文献   

8.
The Early/Middle Miocene (European Land Mammal Zone MN5) localities of Sandelzhausen and Rothenstein 13 in southern Germany have yielded remains of about 13 ophidian taxa: Eoanilius sp. (Aniliidae), Bavarioboa ultima (Boidae), “Coluber” sp., ?Telescopus sp., Natrix sp., cf. Natrix sp., cf. “Neonatrix” sp., unidentified “colubrines” and “natricines” (Colubridae), Naja sp., an unidentified elapid (Elapidae), Vipera sp. (“Oriental viper”), Vipera sp. (“aspis complex”) (Viperidae). Both faunas document a transitional phase from those reported from several late Early and Middle Miocene sites of Central and Western Europe. The climates of Sandelzhausen and Rothenstein 13, as indicated by ophidian fossils, were warm, although not tropical or subtropical.  相似文献   

9.
The fossil fallow deer Dama dama geiselana Pfeiffer from Neumark-Nord (Saxony-Anhalt, Germany) is upgraded to species level and discussed within the current taxonomy of recent and fossil fallow deer. Typical antler and skeletal characteristics are discussed in comparison with the recent Dama dama, Dama mesopotamica and the fossil species Dama clactoniana, Dama nestii and Dama rhenana. The phylogenetic relationship of fallow deer can be traced back to the Late Pliocene and distinguished morphologically from Cervus elaphus, Cervus nippon and Axis axis. Late and Middle Pleistocene finds from Germany are presented and discussed in the context of the finds from the Mediterranean region and Great Britain. The differences in antler morphology and bone dimensions in West German and North-East German fallow deer from the Late Pleistocene support the hypothesis of different immigration channels, on the one hand from the eastern Mediterranean along the Danube and on the other from the west along the Rhone and Rhine. In the Middle Pleistocene, Dama mesopotamica is considered as the typical fallow deer in the eastern Mediterranean, while in the west, Dama clactoniana is widespread. The hypothesis of immigration from the eastern Mediterranean is supported by the fossil record in Germany with the fallow deer from Edesheim. Conversely, Dama geiselana probably influenced East Mediterranean populations. Special tooth characteristics of Dama geiselana occur with lower frequency in Dama mesopotamica. In the Bronze Age, the fallow deer from Kastanas (Macedonia) shares antler characteristics, the high frequency of specific features of the scapula, and the astragalus with Dama geiselana. A relict population of Dama geiselana probably reached the Eastern Mediterranean at the beginning of the last cold stage.  相似文献   

10.
The similar geographic distributions of an extinct (Dasypus bellus) and an extant (D. novemcinctus) armadillo species have long been of interest to scholars because of the unresolved phylogeny. The relationship between the two species has been investigated through morphological and phylogenetic studies, whereas the ecological perspective has been overlooked, the importance of which is more and more acknowledged in speciation events. Here, we used ecological niche models to study the climatic niche similarity of three species of Dasypus (D. bellus, D. novemcinctus, and D. kappleri) and provide new insights on the relationship among them. The climatic niche similarity was compared in two ways: hindcast of ecological niche models based on occurrences and climatic layers, and direct niche boundary comparison along bioclimatic axes. The fossil records of D. bellus were not predicted suitable by the ecological niche models of the two extant armadillos. The direct comparison of niche boundary showed that D. bellus lived in colder and relative dryer climates, with high temperature variation and low precipitation variation. Our results did not support the previously assumed ecological similarity of D. bellus and D. novemcinctus based on their geographic distributions and emphasized the possibility of a cold adapted characteristic of the life history of D. bellus.  相似文献   

11.
The predation potential of a generalist predator Rhynocoris marginatus (Fab.) (Hemiptera: Reduviidae) against three important mealybug pests of cotton, Phenacoccus solenopsis Tinsley, Maconellicoccus hirsutus Green, and Coccidohystrix insolita Green (Hemiptera: Pseudococcidae) was evaluated under laboratory conditions. The specific objective of the study was to determine the prey capturing time, prey handling time, and prey preference among the three mealybug species for different developmental stages of R. marginatus. The number of prey consumed/predator/24 h by R. marginatus was dependent on the mealybug species and the predator developmental stage. Rhynocoris marginatus showed a decrease in prey capturing time and handling time as the predator grew older. After evaluating the prey stage preference, results indicated that the developmental stages of R. marginatus preferred adult mealybugs over the younger stages. In a choice-test bioassay including the three mealybug species, no significant difference in prey species selection was observed for the various R. marginatus developmental stages. However, the mortality of P. solenopsis was observed to be highest among the mealybugs, followed by M. hirsutus and C. insolita. This supports the idea that R. marginatus can be effectively utilized for the management of one of the most destructive mealybug pests of cotton, P. solenopsis. Results from this study are important for the development of a knowledge-based management program for cotton agroecosystems affected by various mealybug pests.  相似文献   

12.
Tooth eruption sequences vary in a non-random way among mammalian species. Several variables have been linked to this, including tooth and jaw shape, adaptations to diet, and food processing. Likewise, changes in eruption patterns correlate with the speed of postnatal growth in some groups, the Schultz’s Rule pattern. Here, the eruption pattern of the permanent dentition in lower jaws from different cervid species have been investigated to discern the effect of these factors and phylogeny as well as to reconstruct the ancestral tooth eruption sequence of cervids. In ruminants, the different patterns of emergence of permanent teeth seem to be best explained by phylogeny. The degree of hypsodonty, age of first molar eruption, and life history parameters such as longevity and age of female sexual maturity do not explain the observed sequential differences in eruption patterns. The Parsimov-based analysis for the ancestral state resulted in a tooth eruption sequence of m1 – m2 – i1 – i2 – i3 – c – m3 – (ppp) for Cervidae; a pattern recorded in Odocoileus, Capreolus, and Hydropotes. The eruption pattern of Caenomeryx filholi, from the Oligocene of Gaimersheim, is identical to the result of the Parsimov-based analysis except for the presence of a first premolar, a tooth lost in cervids.  相似文献   

13.
All materials, including upper and lower jaw fragments and isolated teeth, of two closely related species of the stem placental mammal Prokennalestes, P. minor Kielan-Jaworowska et Dashzeveg, 1989 (258 specimens) and P. trofimovi Kielan-Jaworowska et Dashzeveg, 1989 (251 specimens), from the type locality of Khovoor (Early Cretaceous of Mongolia) are described. These extensive materials allow for the first time the study of morphological and size variability in an Early Cretaceous mammal. Prokennalestes can be diagnosed by the dental formula I?/4, C1/1, P4–5/5, M3/3, presence of the Meckelian groove, the mandibular foramen positioned dorsally on a prominent longitudinal ridge, presence of the masseteric foramen, double-rooted and premolariform lower canine, submolariform P5 with a large protocone and minute metacone, presence of the preparastyle, cusplike postmetacrista, and cusplike conules with incipient conular cristae on the upper molars, premolariform p5, the protoconid distinctly higher than the metaconid, the paraconid and metaconid connate at the base, transverse protocristid, and presence of distal metacristid on the lower molars. Two Prokennalestes species are reliably distinguished by the tooth dimensions (P. minor is smaller by 20%), the position of the infraorbital foramen (under P4 in P. minor and between P4 and P5 or under P5 in P. trofimovi), the presence of protoconal swelling on P4 (usually absent in P. minor and usually present in P. trofimovi), the ectocingulum extension in M3 (longer in P. minor), position of the posterior end of the mandibular symphysis (under p2 in P. minor, under p2–p3 in P. trofimovi), and by the position of the posterior mental foramen (under p4 in P. minor and under p5 in P. trofimovi). Taking into account considerable morphological differences between the two samples, they are regarded as different species rather than sexual morphs of the same species. Prokennalestes is a basal eutherian mammal similar in phylogenetic position to other stem placentals (Eomaia, Murtoilestes, Bobolestes, Aspanlestes). A more exact phylogenetic position of Prokennalestes can be established based on rigorous phylogenetic analysis including a large set of known stem therian and stem placental taxa.  相似文献   

14.
Of the four species encompassing the genus Pelobates, only two overlap along a narrow contact zone, i.e., Pelobates fuscus and Pelobates syriacus. Our study investigated the shifts in niche similarity of these two closely related species from the Last Interglacial towards the end of the twenty-first century. We computed climatic suitability models using Maxent and projected them onto future and past climates. We used fossil occurrences to test the predictive accuracy of past projections. Niche similarity was assessed between the studied species using Schoener’s D index and a background similarity test. Finally, we evaluated niche differentiation by contrasting the species occurrences using a logistic regression analysis. The ecological niches are slightly extended outside the present geographical ranges in the Caucasus and the Balkans, south for P. fuscus and north and west for P. syriacus, suggesting that their present distribution is not at equilibrium with the climate. The Last Interglacial distribution of P. fuscus included British Isles and broad areas in western, central, and northern Europe, while P. syriacus extended northwards in the Balkans. The validation with fossil records revealed good predictive performance (omission error?=?4.1 % for P. fuscus and 16.6 % for P. syriacus). During the Last Glacial Maximum, climatic suitability persisted in refugia in southern Europe, Pannonian Basin, and Caucasus for P. fuscus, and Israel, southern Balkans, and Caucasus for P. syriacus. Present potential distributions revealed a low similarity of species’ ecological niches, comparable with Last Interglacial, but projections towards 2080 revealed a sharp increase.  相似文献   

15.
Recently, dental microwear analysis has been successfully employed to xenarthran teeth. Here, we present new data on use wear features on 16 molariforms of Orophodon hapaloides and Octodontotherium grande. These taxa count among the earliest sloths and are known from the Deseadan SALMA (late Oligocene). Modern phylogenetic analyses classify Octodontotherium and Orophodon within Mylodontoidea with whom they share lobate cheek teeth with an outer layer of cementum and a thick layer of orthodentine. Similar target areas of 100μm2 were analyzed on the orthodentine surface of each tooth by stereomicroscopic microwear and by SEM microwear. Results were unlike those of extant sloths (stereomicroscopic microwear: Bradypus, Choloepus) and published data from fossil sloths (SEM microwear: Acratocnus, Megalonyx, Megatherium, Thinobadistes); thus, both approaches independently indicate a different feeding ecology for the Oligocene taxa. The unique microwear results suggest that both taxa fed on plant material with low to moderate intrinsic toughness (foliage, twigs) but also proposes intake of tougher food items (e.g., seeds). Frequent gouging of the tooth surfaces can be explained by exogenous influence on microwear, such as possible intake of abrasive grit. We suggest an unspecialized herbivorous diet for Octodontotherium and Orophodon utilizing diverse food resources of their habitat. These interpretations support the reconstruction of (1) Deseadan environments as open habitats with spreading savannas/grasslands and (2) both taxa as wide-muzzled bulk feeders at ground level.  相似文献   

16.
Transgenic hairy roots of Datura spp., established using strain A4 of Agrobacterium rhizogenes, are genetically stable and produce high levels of tropane alkaloids. To increase biomass and tropane alkaloid content of this plant tissue, four Pseudomonas strains, Pseudomonas fluorescens P64, P66, C7R12, and Pseudomonas putida PP01 were assayed as biotic elicitors on transgenic hairy roots of Datura stramonium, Datura tatula, and Datura innoxia. Alkaloids were extracted from dried biomass, and hyoscyamine and scopolamine were quantified using liquid chromatography-tandem mass spectrometry analysis. D. stramonium and D. innoxia biomass production was stimulated by all Pseudomonas spp. strains after a 5-d treatment. All strains of P. fluorescens increased hyoscyamine yields compared to untreated cultures after both 5 and 10 d of treatment. Hyoscyamine yields were highest in D. tatula cultures exposed to a 5-d treatment with C7R12 (16.633 + 0.456 mg g?1 dry weight, a 431% increase) although the highest yield increases compared to the control were observed in D. stramonium cultures exposed to strains P64 (511% increase) and C7R12 (583% increase) for 10 d. D. innoxia showed the highest scopolamine yields after elicitation with P. fluorescens strains P64 for 5 d (0.653 + 0.021 mg g?1 dry weight, a 265% increase) and P66 for 5 and 10 d (5 d, 0.754 + 0.0.031 mg g?1 dry weight, a 321% increase; 10 d 0.634 + 0.046 mg g?1 dry weight, a 277% increase). These results show that the Pseudomonas strains studied here can positively and significantly affect biomass and the yields of hyoscyamine and scopolamine from transgenic roots of the three Datura species.  相似文献   

17.
Cuckoo wasps of the subfamily Amiseginae, Eosega heterotarsata gen. et sp. nov. and Foveorisus kilimniki gen. et sp. nov., from the Late Eocene Baltic (Russia) and Rovno ambers (Ukraine), respectively, are described. Primitive Eosega is close to the extinct genus Palaeobethylus Brues in Kieffer, 1914 and represents the so-called American series of genera of Amiseginae. Foveorisus is found to be morphologically close to a number of extant oriental genera. All known fossil Amiseginae are listed. Stick insects of the family Archipseudophasmatidae, possible hosts of the Eocene amisegines, are recorded in the Rovno amber for the first time.  相似文献   

18.
A new species of Kiluluma Skrjabin, 1916, Kiluluma ornata n. sp., is described from the intestine of the white rhinoceros Ceratotherium simum (Burchell) from South Africa. The new species is virtually identical with a species described as Kiluluma sp., but not named due to a paucity of material then available. The new species most closely resembles K. solitaria Thapar, 1924 and K. ceratotherii Beveridge & Jabbar, 2013, in the possession of an undulating anterior margin of the buccal capsule but differs in the leaf crown elements which have bulbous, lip-like expansions, which are lacking in K. solitaria and K. ceratotherii.  相似文献   

19.
Epizootic disease caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd) is a major driver of amphibian declines, yet many amphibians declined before the pathogen was described. The Relict Leopard Frog, Rana onca (=Lithobates onca), was nearly extinct, with the exception of populations within a few geothermal springs. Growth of Bd, however, is limited by high water temperature, and geothermal springs may have provided refuge during outbreaks of chytridiomycosis. We conducted field surveys and laboratory experiments to assess the susceptibility of R. onca to Bd. In the field, we found Bd at one of the two areas where remnant populations of R. onca still occur, but not in the other. In the laboratory, we infected juvenile frogs from these two areas with two hypervirulent Bd isolates associated with declines in other ranid species. In our experiments, these Bd isolates did not affect survivorship of R. onca and most infections (64%) were cleared by the end of the experiments. We propose that R. onca either has inherent resistance to Bd or has recently evolved such resistance. These results may be important for conservation efforts aimed at establishing new populations of R. onca across a landscape where Bd exists. Resistance, however, varies among life stages, and we also did not assess Bd from the local environment. We caution that the resistance we observed for young frogs under laboratory conditions may not translate to the situation for R. onca in the wild.  相似文献   

20.
Feeding of predatory mites (Phytoseiulus persimilis, Galendromus occidentalis, and Neoseiulus cucumeris) on different life stages of Tetranychus atlanticus under optimal conditions was studied. Daily and total consumption of prey by predators and selection of prey of different life stages were studied for 5 days and for the entire feeding period. Average daily food consumption [number of individuals] for the entire life period of mature mite females constituted 0.43 females + 5.0 [nymphs and males] + 3.4 eggs of Tetranychus atlanticus in P. persimilis; 0.12 females + 3.70 [nymphs and males] + 3.10 eggs in G. occidentalis; and 0.19 females + 4.10 [nymphs and males] + 3.50 eggs in N. cucumeris. During the entire period of feeding, P. persimilis preferred large individuals and at the postembryonic stages selected prey to a greater extent than G. occidentalis and N. cucumeris (61.8 and 55.1%, respectively). The use of a 5-day express-method is possible for estimation of some biological characteristics of phytoseiids that previously consumed the same food for a long period. In other cases, analysis of characteristics for the entire life period is necessary.  相似文献   

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