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1.
Several traces of biological interaction were found on penguin bones from the basal levels (Aquitanian) of the Miocene Gaiman Formation in the lower Chubut valley of the Provincia del Chubut, Argentina. The fossil-bearing beds were deposited in littoral to sublittoral environments within sediments of mostly pyroclastic origin. We interpret many traces to have been produced by predators and/or scavengers while the penguins were still in a breeding area. Many bones show cracking marks due to aerial exposure. The material is disarticulated as is usual in recent breeding areas. Potential predators were coeval terrestrial mammals, most probably marsupial carnivores. After a marine transgression, these bones were buried or exposed on the sea bottom where they could be colonized by algae, sponges, cnidarians, and other benthic organisms. We identified sponge borings in several bones. Other traces are interpreted to have been produced by echinoderms feeding on sponges or algae. No evidence of other invertebrate predators such as muricid or naticid gastropods, or decapods was found. Finally, other traces appear to have been generated by shark and possibly teleostean vertebrates feeding on epibionts. One coracoid is interpreted to have been marked by a shark that is common in the Gaiman Formation, the carcharhiniform Galeocerdo aduncus. From an ethological (Seilacherian) classification, traces on bones from the Gaiman Formation include Domichnia (sponge perforations), Praedichnia (terrestrial marsupials, sharks, teleosteans) and Pasichnia (echinoderms). Remarkably, remains of marine organisms with skeletons made of calcium carbonate are very poorly preserved in the Gaiman Formation. Only large oysters, sparse shell fragments, skeletal moulds, and bioturbation is evident. The fossil assemblage is mainly composed of phosphatic (e.g. teeth, bones, crustacean parts) and siliceous (sponge spicules, diatoms) remains.  相似文献   

2.
The effects of biodegradation and heating on the stable carbon, nitrogen, hydrogen and oxygen isotope ratios of chitin in arthropods were studied. Chitinous exoskeletons from seven aquatic arthropod species were subjected to anaerobic marine biodegradation in mud, to terrestrial biodegradation in soils, and to thermal degradation under anaerobic and aerobic conditions. The isotope ratios of chromatographically separated D-glucosamine hydrochloride and derivatives from treated and untreated specimens were then compared. Carbon, nitrogen, oxygen and hydrogen stable isotope ratios were all found to be conserved during partial degradation of chitin. Micromorphological comparative studies using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) indicated that no fungal chitin or other contaminants were present in the chitins that were chemically isolated from biodegraded substrates. Our results indicate that it will be possible to use stable isotope ratios of archaeological chitin samples for environmental and climatic reconstructions. An illustration of the utility of this approach comes from the observation that the stable isotope ratios of chitin from crustacean exoskeletons recovered from archaeological sites with ages up to 1400 years bp are in good agreement with measurements on modern crustaceans from similar environments.  相似文献   

3.
Stein, M., Salisbury, S.W., Hand, S.J., Archer, M. & Godthelp, H., December 2012. Humeral morphology of the early Eocene mekosuchine crocodylian Kambara from the Tingamarra Local Fauna southeastern Queensland, Australia. Alcheringa 36, 473–486. ISSN 0311-5518.

Mekosuchines (Crocodylia; Crocodyloidea) were a clade of crocodylians endemic to Australia and the South Pacific that underwent radiation during the Cenozoic. Numerous questions about mekosuchine palaeoecology remain unanswered. Tantalizing among these is the possibility that some mekosuchines were primarily terrestrial. To date, studies of mekosuchines have focused mainly on the cranium. However, the morphological signal for terrestriality is more likely to be found in the postcranial skeleton. Here, we present a comparative morphological study of fossil humeri referable to Kambara from the early Eocene Tingamara Local Fauna, Murgon, southeastern Queensland. The humeri of Kambara do not show the torsion between the proximal and distal extremity seen in extant crocodylians, illustrated here with Crocodylus porosus and Crocodylus johnstoni. They also differ in the structure of the medial and lateral condyles of the distal extremity. When the effects of these features on musculature and articulation are considered, it appears that the forelimb of Kambara could have facilitated a greater force at the glenohumeral joint and possibly swung the lower forelimb faster with a greater arc of motion than Australia's extant crocodylians. This is conducive to an improved capacity for both terrestrial locomotion and paraxial swimming. Although the former case suggests that Kambara may not have been as closely tied to water as extant crocodylians, it is unusual given the typically broad rostra of the cranium. Among crocodylians this is a common characteristic of semi-aquatic ambush predators. This study shows the utility of the postcranial skeleton in interpreting crocodylian palaeoecology.

Michael Stein [michael.stein@student.unsw.edu.au] (corresponding author), Suzanne J. Hand [s.hand@unsw.edu.au], Michael Archer [m.archer@unsw.edu.au] and Henk Godthelp [h.godthelp@unsw.edu.au], School of Earth and Environmental Science, University of New South Wales, Sydney, NSW, 2052, Australia; and Steven W. Salisbury [s.salisbury@uq.edu.au], School of Biological Sciences, University of Queensland, Brisbane, Qld, 4072, Australia. Received 13.1.2012, revised 24.2.2012, accepted 28.2.2012.  相似文献   

4.
When Ogygoptynx wetmorei was reported by Rich & Bohaska (1976), it appeared to represent a unique and new avian group. Detailed comparisons of this Early Paleocene form from Colorado (USA) have clearly demonstrated that it is distinct from North American protostrigids and all European Palaeogene owls and that it is intermediate between the modern typical owls (Strigidae) and barn owls (Tytonidae). A new monotypic family of owls, the Ogygoptyngidae, is proposed to include this form.  相似文献   

5.
A new macropodine genus and species, Silvaroo bila, is described from the Pliocene Chinchilla Sand of Queensland. The generic concept of Protemnodon is reviewed, and it is concluded that two Pliocene species previously placed in that genus (bandharr and buloloensis) belong in Silvaroo. Species of Silvaroo resemble the modern forest wallabies of Papua New Guinea (species of Dorcopsis and Dorcopsulus) and also bear close phenetic resemblance to the late Miocene Dorcopsoides fossilis. Forest wallabies are not known from mainland Australia after the middle Pliocene, but occur in the late Pliocene and Pleistocene of New Guinea.  相似文献   

6.
This paper presents archaeological observations and results of palaeoecological and geo-chemical analyses of archaeological deposits from two rural sites in northernmost Norway. These are combined with climate data and the first period of continuous monitoring of soil temperature, moisture, and redox potential in sections. This data constitutes the basic research material for evaluations of conservation state and preservation conditions. The data has been collected in collaboration with the partners of a cross-disciplinary project: ‘Archaeological Deposits in a Changing Climate. In situ Preservation of Farm Mounds in Northern Norway’ funded by the Norwegian Council for Research (http://www.niku.no/en/archaeology/environmental_monitoring/archaeological_deposits_in_a_changing_climate_in_situ_preservation_of_farm_mounds/). This is an important Norwegian research initiative on monitoring of rural archaeological deposits, and the results have consequences for heritage management of a large number of sites from all periods. Palaeoecological analyses and redox measurements have revealed ongoing decay that might not otherwise have been detected. Decay studies indicate that both site types may be at risk with the predicted climate change. Some mitigating acts are suggested.  相似文献   

7.
A new heterosporous fern species, Azolla boliviensis sp. nov., is described from latest Maastrichtian (latest Cretaceous) to Paleocene (earliest Palaeogene) terrestrial sediments of the Eslabón and Flora Formations, Subandean belt, Bolivia. The species is represented by dissociated but abundantly co-preserved megasporocarps, megaspores, microsporangia, massulae and microspores. The genus consistently characterizes warm-climate lacustrine settings. Fossil Azolla is first identified around the Early to mid-Cretaceous but the genus apparently underwent dramatic radiation during the Late Cretaceous. Abundant Azolla remains in Bolivia add to this portrait of rapid geographie dispersai and diversification near the close of the Cretaceous. The ranges of many Azolla species span the Cretaceous- Palaeogene boundary and the potential of Azolla to withstand altered environmental conditions, such as periodic frost damage, drought, and salinity change, and its ability to undergo rapid vegetative regeneration in association with nitrogen-fixing cyanobacterial symbionts, suggest that the survival of this group was favoured during the adverse conditions of the end-Cretaceous event.  相似文献   

8.
It is long been thought that many flake attributes, including both size and shape, are largely due to the morphology of a core’s flaking surface, yet this has never been tested under strictly controlled conditions. Using molded glass cores with surface morphologies that highly resemble prehistoric ones, this experiment demonstrates that while core surface morphology does exhibit some influence on flake size and shape, a high degree of variation in flakes produced with the same core surface morphology shows that the effects of other independent variables, such as exterior platform angle and platform depth, have an even stronger effect. A major implication of these results is that current approaches to reconstruct prehistoric knapping strategies are overlooking significant sources of variation.  相似文献   

9.
Bone collagen stable nitrogen isotope values are reported for modern kangaroos (Macropus spp.) from eight field sites along a 1160 km south–north transect from temperate coastal to arid interior South Australia, in order to investigate δ15N tissue variability in relation to rainfall and relative humidity. Mean annual rainfall along the transect ranges from 775 mm at Mount Gambier in the southeastern coast to 176 mm at Innamincka in the arid northern interior, while 3pm relative humidity ranges from 73% at coastal Flinders Chase to 36% at Innamincka. In arid habitats (176–238 mm rainfall), the δ15N values of kangaroo bone collagen become more positive in relation to decreasing mean annual rainfall (r2 = 0.98), while there is only a weak correlation with relative humidity (r2 = 0.67). In contrast, in temperate and semi‐arid coastal habitats (350–775 mm), there is no correlation between kangaroo bone collagen δ15N values and rainfall (r2 = 0.0011) or between δ15N values and relative humidity (r2 = 0.0035). Thus, in South Australia, kangaroo bone collagen δ15N values do not show a simple linear correlation with either rainfall or relative humidity across all habitats. These results suggest that stable nitrogen isotope analyses of herbivore bones obtained from archaeological and palaeontological sites may provide a reliable proxy for past rainfall values in arid‐land ecosystems. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

10.
Zooarchaeologists have often employed studies of bone fracture morphology as a means of understanding past human cultural activity, and various methodological approaches have been developed for analyzing archaeological broken bone assemblages. It is widely understood that bones degrade over time, however, few studies have attempted to define and quantify the rate at which bones degrade and fracture morphologies change. This study examines degradation in frozen bones (−20 °C) and bones exposed to hot (40 °C) dry conditions. These two simulated environmental conditions represent extreme real-world climates, and allow for an actualistic understanding of the rates of degradation that bones experience in nature. When frozen, bones degrade slowly but significantly, and demonstrate measurable differences in samples frozen for 1, 10, 20, 40, and 60 weeks. In hot, dry conditions, bones degrade very quickly, and demonstrate measurable differences after 1, 3, 7, 14, and 21 days. These data allow for a more detailed understanding of the relationship between the cultural and natural processes that result in bone fracture, and the time period during which bones can be expected to maintain fresh fracture characteristics. This research also has implications for understanding human subsistence and survival strategies and for interpreting the archaeological record.  相似文献   

11.
An oak timber was discovered in 2013 within intertidal peats at the Bay of Ireland, Stenness, Orkney, representing a unique archaeological find. Subsequent excavation and rescue of the timber took place in 2014 to investigate its stratigraphical relationship before further eroding. Dendrochronological and morphological study identified the timber as a possible radially split log, c. 150 years of age when felled. No dendrochronological match was possible, and a wiggle-match date obtained provided a Later Mesolithic felling date of 4410–4325 cal BC. This timber is the first and only evidence so far for the use of oak in Mesolithic Orkney. The timber is significant palaeoecologically, suggesting oak may have been indigenous to Orkney. This adds to a growing argument for the existence of areas of “true woodland”. Pollen evidence shows the timber was deposited within reedswamp, fringed by willow-birch carr-woodland, with oak unlikely to have been growing in the immediate location. High microscopic and macroscopic charcoal values indicate Later Mesolithic communities exerted influence on this wetland using burning as a tool for landscape modification. It is unknown what the timber represents; it may have been for construction purposes or as a marker/possible landing place showing the path to the Loch of Stenness.  相似文献   

12.
New data regarding the white shark (Carcharodon carcharias) at the archaeological complex Huaca Pucllana (200–700 ad ) are presented on the basis of the recent discovery of teeth in ritual offering features. Previous information of this species from fossil, archaeological and modern records is reviewed. The use of the white sharks as an El Niño indicator is rejected. Past and present white shark distribution in the South East Pacific is reviewed, and the extermination of pinniped colonies as a factor in the poor modern record is discussed. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

13.
河南信阳城阳城遗址M8为高等级战国晚期楚国贵族墓,该墓出土了以漆木器为主的各类文物400余件,其中尤以黑、红两色竹蔑编织而成的髹漆竹席最为精美。为开展彩漆竹席脱水保护提供基础数据,采用激光共聚焦显微镜、拉曼分析仪和傅里叶红外吸收光谱仪(FTIR)及扫描电镜-能谱(SEM-EDS)等现代分析仪器对竹席漆膜的成分及表面形态进行了分析,并在此基础上,结合传统髹漆文献资料探讨了漆膜的制作工艺。结果表明:城阳城彩席中的黑色漆膜为大漆自然显色,红色漆膜是大漆掺加朱砂调制而成;黑色漆膜表面较为平整,漆膜与胎体结合紧密,红色漆膜表面相对粗糙,结构较为疏松;竹席漆膜的厚度在0.02~0.03 mm之间,应是由大漆涂刷至少3~5次制备而成。研究结果可为下一步的彩漆竹席的脱水保护及展示提供基础数据。  相似文献   

14.
Campanile rupicolum sp. nov. is described from the early Miocene Upper Maude Limestone Member of Maude, Victoria. The genus has not hitherto been recorded from Victoria, a part of the Southeast Australian biogeographic Province, and was thought to be characteristic of the Austral-Indopacific Province. This is the oldest occurrence of the genus so far recorded from Australia.  相似文献   

15.
Nel, A., Roques, P., Prokop, J., & Garrouste, R., 11 September 2018. A new, extraordinary ‘damselfly-like’ Odonatoptera from the Pennsylvanian of the Avion locality in Pas-de-Calais, France (Insecta: ‘Exopterygota’). Alcheringa 43, 241–245. ISSN 0311-5518.

Enigmaptera magnifica gen. et sp. nov., type genus and species of the new odonatopteran family Enigmapteridae, is described from the Moscovian of Avion (northern France). It is the sister group of the major clade Neodonatoptera, placed together in the new clade Paneodonatoptera. Its wing venation has characters never found in other Odonatoptera. It is a further case of convergent wing petiolation in this superorder. Enigmaptera magnifica, like the protozygopteran Jacquesoudardia magnifica from the same outcrop, probably lived like the extant damselflies along the shores of lakes and rivers, hunting the small insects found in the same deposits. These discoveries show that very small insects were significant elements of the entomofaunal diversity and trophic chains of the Late Carboniferous ecosystems.

Romain Garrouste ] Institut Systématique Evolution Biodiversité (ISYEB), Muséum national d’Histoire naturelle, CNRS, Sorbonne Université, EPHE, 57 rue Cuvier, CP 50, 75005 Paris, France; Patrick Roques ] Allée des Myosotis, Neuilly sur Marne, F-93330, France.; Jakub Prokop ] Charles University, Faculty of Science, Department of Zoology, Vini?ná 7, CZ-128 44, Praha 2, Czech Republic.  相似文献   


16.
The World Heritage Site of Bryggen in Bergen, Norway, has experienced significant degradation of archaeological deposits as a consequence of changes in the soil water and groundwater balance after urban redevelopment adjacent to the heritage site. Additionally, groundwater temperatures below the heritage site were found to be significantly higher closer to the redeveloped area. One of the main mitigation measures taken to reduce the degradation of the archaeology has been the construction of a hydrological barrier along the sheet piling that divides the redeveloped area and the historic site. A shallow subsurface infiltration system was designed to achieve groundwater levels and flow conditions that are optimal for the preservation of archaeological remains directly along the sheet pile, while reducing drainage and subsidence also further upstream. Monitoring of groundwater level and temperatures after implementation of the hydrological barrier shows that groundwater levels and flow conditions have improved with respect to optimal preservation conditions, and groundwater temperatures have generally been reduced by up to 2 °C.  相似文献   

17.
Access to the lower limbs from a historically-identified nineteenth century below-knee amputee who had worn a hardwood ectoprosthesis for an extended time prior to death provides a natural experiment for investigating the morphological and histological effects of the resulting altered mechanical environment. Osteometry (measuring total bone size), cross-sectional geometry (bending and axial rigidity) and histology (bone turnover rate) are assessed. A reduction in size and geometric strength, along with an increase in cortical bone turnover, indicate that the midshaft and distal regions from the affected femur were partially shielded from functional strain. Structural compliance of the prosthesis, probably originating from design and material of manufacture, to some degree preserved the mechanical and morphological integrity of the proximal subtrochanteric region. The results of this case study are consistent with contemporary theory in skeletal biomechanics, for example, Frost's Mechanostat, which suggests that insufficient functional strain promotes intracortical remodelling and endosteal expansion.  相似文献   

18.
Strontium isotope values (87Sr/86Sr) in bone and tooth enamel have been used increasingly to identify non-local individuals within prehistoric human populations worldwide. Archaeological research in the Midwestern United States has increasingly highlighted the role of population movement in affecting interregional cultural change. However, the comparatively low level of geologic variation in the Midwestern United States might suggest a corresponding low level of strontium variation, and calls into question the sensitivity of strontium isotopes to identify non-local individuals in this region. Using strontium isotopes of archaeological fauna, we explore the degree of variability in strontium ratios across this region. Our results demonstrate measurable variation in strontium ratios and indicate the potential of strontium analysis for addressing questions of origin and population movement in the Midwestern United States.  相似文献   

19.
20.
Abstract

This paper explores the case of the Khami archaeological site, whose degradation by the local communities in recent years was as a result of socio-economic problems caused by the collapse of the Zimbabwean economy combined with the inability of the Zimbabwean government to support the site. We argue that the negative attitude by the local communities towards the management of cultural heritage sites is embedded in the colonial history of the country, and has been driven by the socio-economic difficulties emanating from the collapse of the Zimbabwean economy in recent years. We begin by explaining the history of Khami, its architecture, and the local communities residing around it. We then show and assert that the subsequent degradation of Khami and the landscape around it by the local communities is linked to the socio-economic problems of the country and poverty, which emanated from the collapse of the Zimbabwean economy. In the end, we contend that the economic constraints are part of the reasons why the local communities have from time to time failed to respect the importance of protecting cultural heritage sites in the country.  相似文献   

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