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1.
Machaeridians are an enigmatic group of multisclerite-bearing benthic marine invertebrates, known from Lower Ordovician to Pennsylvanian rocks. They receive almost no attention, but are very common fossils, especially in faunas of Middle Ordovician to Early Devonian age. Evidence that machaeridians form a monophyletic group includes many shared derived morphological features of their sclerites, and their highly characteristic mode of sclerite formation. Machaeridian sclerites are calcitic, and feature an outer sclerite layer formed by marginal accretion, and an inner layer formed by serial addition of calcite elements in linear series radiating from the sclerite umbo. The class Machaeridia is understood herein to comprise the order Turrilepadomorpha Pilsbry, 1916, including the families Turrilepadidae Clarke 1896 and Plumulitidae Jell 1979, and the order Lepidocoleomorpha Schallreuter 1985, including the family Lepidocoleidae Clarke 1896. The latter family is unique in the possession of a dorsal tongue and groove hinge by which opposing sclerites of a given body segment articulated. All machaeridian species have distinct dextral and sinistral sclerite morphologies. All lepidocoleid species, and isolated members of some other families, are enantiomorphic, with some right-handed and some left-handed individuals. Recent classifications have united machaeridians with other problematic groups, including tommotiids, sachitids, and hercolepadids. Such proposed relationships have very weak evidential bases, and should be rejected.  相似文献   

2.
A small assemblage of isolated Microdictyon plates is described from the lower Cambrian Ajax Limestone, Mt Scott Range (Flinders Ranges), South Australia. Microdictyon plates are primarily known from single, isolated, perforated phosphatic sclerites; only one species (M. sinicum) from the Chengjiang Lagerstätte is known from soft-bodied preservation of the complete organism. The isolated plates from South Australia display a wide range of morphologies potentially reflecting: 1, considerable diversification within the group at this time; 2, extensive intraspecific morphological variation; 3, different plate morphotypes along the trunk of the animal; or 4, significant ontogenetic variation in successive growth stages. The South Australian specimens are similar to several individual sclerites described from other Cambrian palaeocontinents, but appear closest to faunas described from South China. Problems associated with the taxonomy of isolated Microdictyon plates are discussed, including the lack of knowledge associated with intraspecific and/or ontogenetic variability and how individual plate morphology may relate to size or relative position along the length of the complete organism.  相似文献   

3.
The acid insoluble sclerites of Thambetolepis delicata gen. et sp. nov. of late Tommotian or immediately post-Tommotian age from near Ardrossan, South Australia, are described. These sclerites, as well as those of Sachites Meshkova 1969 and Halkieria Poulsen 1967, are from multi-sclerite animals similar to Wiwaxia Walcott 1911 together with which they constitute the new class Thambetolepidea. Biological affinities of these fossils are discussed in the light of the complex internal structure of the sclerites. Possible assignments to the opisthobranch gastropods, the polyplacophorans, or the annelids are discussed but the taxonomic position of Thambetolepis and the Thambetolepidea is unresolved.  相似文献   

4.
Scavenging is one of the primary taphonomic processes shaping the final composition of fossil faunal assemblages. The taphonomic effect of scavengers is variable and must be understood in the context of the causes of that variation. In this study, we investigated relationships between the El Niño Southern Oscillation (ENSO), variable rainfall and scavenging on 20–40 kg mammal carcasses in semi‐arid New South Wales over four years. Following periods of above‐average rainfall (coincident with the La Niña phase of the ENSO), there was an increased availability of non‐carrion food and scavenging activity was moderate. Following below‐average rainfall (coincident with the El Niño phase of the ENSO), foraging options diminished, leading to a greater importance of carrion in the diet of scavengers and a resultant increase in carcass disturbance, transport and destruction by scavengers. Feral pigs (Sus scrofa) and red foxes (Vulpes vulpes) were the most taphonomically significant scavengers in the study. Australian ravens (Corvus coronoides) and wedge‐tailed eagles (Aquila audax) were active scavengers throughout the period of the study, but had little impact on bone survival. Lace monitors (Varanus varius) also fed mostly on soft tissue and were only present seasonally. We found that climate variability in the form of short‐term oscillation can result in significant variation in the impact of scavengers on carcasses and may be an important consideration when evaluating site formation scenarios and biases in fossil faunal assemblages. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

5.
SUMMARY: The recovery of a large closely dated assemblage that can be unambiguously associated with a mid to late 18th-century Cambridge coffeehouse provides the first opportunity for a detailed consideration of material associated with these significant institutions. A cellar located off All Saints’ Passage in Cambridge, England, backfilled c. 1775–80, produced a substantial assemblage of over 500 objects; principally ceramics, but also including vessel glass, clay tobacco pipes, animal bone and other material. Marked items and assemblage composition allows this material to be unambiguously associated with Clapham’s Coffeehouse, run by William and Jane Clapham c. 1746/48–79. Relatively few archaeological assemblages related to these important 18th-century socioeconomic institutions have been recovered and the material associated with Clapham’s Coffeehouse possesses a distinctive ‘signature’, albeit one that is not necessarily generally applicable to other coffeehouses. There were a substantial number of ceramics associated with tea drinking. Coffee-drinking vessels were frequent but less common and there was relatively little evidence for chocolate drinking. A range of alcoholic drinks were also consumed and dining was common, with a particular emphasis on snacks, whilst smoking appears to have been uncommon. The assemblage is compared with other groups associated with coffeehouses, a series of groups from earlier inns in the vicinity and broadly contemporary domestic assemblages from Cambridge and inn groups from England. The archaeological evidence indicates that the materialities of coffeehouses were not significantly different to that of other establishments, such as inns, and challenges some currently held views of coffeehouses derived from documentary sources.  相似文献   

6.
Identifying the behavioural patterns of bone collecting animals is a crucial aspect of taphonomic studies. Although many studies have established criteria for identifying animal‐collected or animal‐modified bones, very few papers describe the distinguishing features of fox‐made bone assemblages. The bone assemblage collected in an inactive underground stone mine in Potok‐Senderki (Poland) is diagnostic of a red fox (Vulpes vulpes) den. This site provides an ideal opportunity to develop an understanding of the bone collecting behaviour of red foxes in cave‐like environments. This study showed that bones collected by red foxes are concentrated in clusters. The bones represent a broad spectrum of local fox prey species, with most bones showing the marks of gnawing. Each cluster may contain from <10 to >100 bones. Furthermore, the long axes of the bones in clusters frequently show specific orientation. The analysis of bones at this site might make an important contribution towards the establishment of baseline criteria for the identification and evaluation of fox‐accumulated bone assemblages. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

7.
Abstract

We describe six cervid bones — a distal humerus, three distal tibiae, and two astragali — from two Roman sites, São Pedro Fronteira and Torre de Palma, in the Alentejo of Portugal. They are identified on morphological and osteometric grounds as fallow deer, Dama dama. They represent the earliest Holocene evidence for this species in Portugal, and it is suggested that, like the camel, the Romans were responsible for its spread within their Empire. While remains of this animal have not so far been reported in any Moslem period assemblages, there is documentary evidence for the existence of fallow deer in Portugal in the 12th and 13th centuries AD, although the possibility that fallow deer disappeared with the end of Roman rule should be considered.  相似文献   

8.
Although written sources indicate that falconry or hawking was very popular already in early medieval Poland, there is no hard zooarchaeological evidence that would support it. So far, only two studies based on animal remains suggested hawking in medieval Poland. The purpose of this study was to examine all published zooarchaeological reports from all archaeological sites in Poland and check for possible clues of hawking. Altogether, 281 remains of 12 species of diurnal birds of prey were recorded from 38 sites (49 time‐site units) in Poland beginning from the Middle Ages onward. The most frequently found was the goshawk Accipiter gentilis followed by the white‐tailed eagle Haliaeetus albicilla and the sparrowhawk Accipiter nisus. Clues of possible hawking include high status of sites, occurrence of species used in falconry outside their natural ranges, preponderance of females, the presence of sub‐adult specimens and others. It is suggested that surface damage observed on prey bones done by the hawks' beaks and claws may be an extra evidence of hawking. The present study strongly supports the notion that hawking was a very popular activity in medieval Poland. In the future, medieval bone assemblages should always be checked for clues of hawking. The present study may also be used as a source of raw data for other analyses because it includes detailed information on birds of prey from all zooarchaeological reports published so far in Poland. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

9.
Past approaches to the Weight Method (use of the weight of excavated bone assemblages to evaluate the relative potential meat yield of the animals from which they came) are critically reviewed. They do not account for both inter-taxon and intra-taxon variability in the relationship between bone weight and total body or soft tissue weight. Critics of the Weight Method have assumed that these problems are insurmountable. It is argued here that they can be overcome practically. Solutions lie in the integration of classic Weight Method approaches, which assume a consistent ratio of bone weight to body weight between different taxonomic and size groups, with the understanding of animal scaling provided by studies of skeletal mass allometry. Allometric equations derived from original data (regarding cod, Gadus morhua) and available from published sources (regarding mammals and birds) are used to illustrate this argument. Three practical approaches to the Weight Method are suggested and briefly explored, using bone weight data from Earls' Bu, a Norse site in Orkney, Scotland, as a case study.  相似文献   

10.
This article takes up the recent interest in assemblage theory in urban geography and considers the potential for art to contribute to our narrations of urban assemblages. In particular, it uses Chris Ware's recent magnum opus, Building Stories, as not only an account of the urban as an assemblage, but to indicate more broadly the way in which comics might be used to narrate urban assemblages in ways that highlight their multiplicity and plurivocality. The article draws out three themes in its analysis of Building Stories: more-than-human subjects, the various temporalities of the city, and the way memory and narrative are emergent from urban assemblages.  相似文献   

11.
In many parts of Eurasia, the Middle East and Southeast Asia where native wild suids occur, it is notoriously difficult to differentiate these from introduced domestic pigs in the prehistoric archaeological record. Yet, correct identification of the initial appearance or introduction of domestic pigs (Sus scrofa ) is essential for determining the timing for the transition from purely hunting to the adoption of managed animal populations within different regions across the globe. In a recent review of techniques used by zooarchaeologists to distinguish between domestic and wild pig populations, the analysts concluded that the most reliable method was metrical analyses, when the data produce a clear two‐population pattern, one domestic, the other wild. In this study, we demonstrate how linear metrics are an effective tool, albeit at different levels of confidence, for differentiating the native and endemic species of Philippine pig from S. scrofa , both within modern contemporary assemblages, and the archaeological record. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   

12.
13.
Ten species of phosphatic or phosphatised fossils are described from the Early Cambrian Todd River Dolomite of the Amadeus Basin in central Australia. The tannuolinid genus Micrina nov. is erected to include Platyceras etheridgei Tate 1892. The family Kennardiidae nov. is erected to include phosphatic organisms having three distinct forms of mitral sclerite. Assigned to this family are Kennardia reticulata gen. et sp. nov. and tentatively Dailyatia ajaxBischoff. Other phosphatic problematica are Paterimitra pyramidalis gen. et sp. nov., Eccentrotheca cf. kanesia Landing, Nowlan & Fletcher. Also described are phosphatised Chancelloria sp., Lenastella sp. and Pelagiella sp. and the phosphatic inarticulate brachiopods Askepasma toddensegen. et sp. nov., Edreja aff. distincta Koneva and ?Lingulella sp. Two species of tubular problematica are illustrated but not discussed in detail.  相似文献   

14.
Palynofloras from an outlier of Tertiary sediments in the One Tree Hill area north of Adelaide are nonmarine and correlate with similar assemblages from Middle Eocene North Maslin Sands from Maslin Bay and Golden Grove. Although there are similarities with time-equivalent Lower Nothofagidites asperus Zone palynofloras in the Gippsland Basin, a number of species in the South Australian palynofloras do not extend below the Late Eocene in the Gippsland sequences. This indicates earlier appearances for these species in southcentral Australia. The sediments overlie a highly weathered bedrock palaeosurface, indicating that a phase of significant weathering occurred prior to the Middle Eocene. A number of selected taxa are illustrated and their distribution in the palynofloras is discussed. Two new species, Proteacidites mildenhallii and Proteacidites parrawirrensis, are described and one species, Rhoipites byfieldensis, is emended.  相似文献   

15.
Micromammalian bone assemblages from modern pellets of the strigiform Bubo virginianus magellanicus, from the upper Atuel River (southern Mendoza, Argentina), were taphonomically analysed. The results allow us to place B. v. magellanicus in the category of intermediate modification (Category 2). This sample has also been compared with results from other members of this genus, in order to classify B. v. magellanicus as a taphonomic agent. The participation of the Bubo species in archaeological accumulations has been documented, but in Argentina, the role of B. v. magellanicus has been reported up to the present. It is partly because of the sequence of one archaeological site in the south of Mendoza Province called Laguna El Sosneado‐3 (LS‐3). However, considering the absence of a current taphonomic model of this owl, this participation was mentioned as a hypothesis. In the current investigation, archaeological and modern samples have been compared. The results indicate that the skeletal element assemblages recovered from LS‐3 were accumulated by strigiform birds. Taphonomical evidence of light modifications on units I and IV indicates that Tyto alba (Category 1) was probably the main species involved in these units, whereas the taphonomical evidence on skeletal element assemblages recovered from units II and III suggests the action of a strigiform with a major category of modification such as B. v. magellanicus. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

16.
ABSTRACT

In Palau, Micronesia, marine resources, particularly shellfish, played a vital role in human subsistence for millennia. Despite the vast array of molluscan species in archaeological assemblages, there is a dearth of data on nearshore palaeoecology or prehistoric shellfish foraging practices. In this study, we analysed stable oxygen isotopes (δ18O) values present in the calcium carbonate shell of Gibberulus gibberulus from the Chelechol ra Orrak archaeological site to reconstruct average nearshore sea-surface temperatures (SST) from approximately 1500–1100 cal BP. Modern shellfish samples and environmental data were collected from intertidal zones near the site and x-ray diffraction (XRD) was employed to identify the biomineralogical composition of G. gibberulus. These steps provide necessary information for the selection of the proper oxygen isotope-to-SST conversion formula. The selected formula was applied to δ18O samples from archaeological shells to reconstruct prehistoric SST averages. The results of this proxy validation study verify that G. gibberulus accurately records ambient SST and can be used to reconstruct ancient nearshore conditions. These findings also contribute to the establishment of an environmental baseline, which can be used to examine how environmental changes may have influenced the availability of molluscan taxa that in turn influenced human subsistence practices through time.  相似文献   

17.
The term avian osteopetrosis is used to describe alterations to the skeletal elements of several species of domestic bird, most typically the chicken, Gallus gallus domesticus (L. 1758). Such lesions are routinely identified in animal bones from archaeological sites due to their distinctive appearance, which is characterised by proliferative diaphyseal thickening. These lesions are relatively uncomplicated for specialists to differentially diagnose and are caused by a range of avian leucosis viruses in a series of subgroups. Only some avian leucosis viruses cause the development of such characteristic lesions in osteological tissue. Viraemia is necessary for the formation of skeletal pathology, and avian osteopetrosis lesions affect skeletal elements at different rates. Lesion expression differs by the age and sex of the infected individual, and environmental conditions have an impact on the prevalence of avian leucosis viruses in poultry flocks. These factors have implications for the ways in which diagnosed instances of avian osteopetrosis in archaeological assemblages are interpreted. By integrating veterinary research with archaeological evidence for the presence of avian leucosis viruses across Western Europe, this paper discusses the nature of these pathogens, outlines criteria for differential diagnosis, and offers a fresh perspective on the human‐aided movement of animal disease in the past through investigation of the incidence and geographic distribution of avian osteopetrosis lesions from the first century BC to the post‐medieval period. © 2017 The Authors International Journal of Osteoarchaeology Published by John Wiley & Sons Ltd.  相似文献   

18.
Thirty ammonite taxa are recognised in the Wangarlu Mudstone of the Bathurst Island Group from the Cox Peninsula and Shoal Bay, Northern Territory, Australia. Included are a new heteromorph genus Notostreptites, type species N. exilis, and four additional new species and subspecies: Pseudhelicoceras gracilis, Labeceras (L.) tumidum, Labeceras (Appurdiceras) decorum, and Idiohamites dorsetensis laticostatus. The assemblage is best collectively correlated with the Mortoniceras (M.) inflatum Zone of the standard European Albian zonation but some of its members may represent the lower part of the Stoliczkaia dispar Zone. It is broadly correlative with faunas from the Eromanga Basin, which relate to an extensive eastern Australian Late Albian epicontinental sea, but is strikingly different in aspect. The Wangarlu Mudstone assemblage has relatively high diversity and an abundance of cosmopolitan heteromorph taxa well known from Europe and elsewhere, whereas Eromanga Basin assemblages are of relatively low diversity and dominated by Austral heteromorph genera known only from Australasia, southern Africa and Malagasy. The Austral character of Eromanga Basin assemblages is attributed to evolution in a restricted epicontinental sea environment and modest dispersal whereas the continental margin position of the Wangarlu Mudstone ensured an influx of pandemic elements drawn from the mid-Cretaceous world ocean.  相似文献   

19.
Mack, C.L. & Milne, L.A., 19.2.2015. Eocene palynology of the Mulga Rocks deposits, southern Gunbarrel Basin, Western Australia. Alcheringa 39, xxx–xxx. ISSN 0311-5518

Late Eocene palynomorph assemblages have been recovered from carbonaceous sediments within a tenement centred on the Mulga Rocks uranium deposits, currently under exploration by Energy and Minerals Australia. The Mulga Rocks deposits occur in a palaeovalley incised into rocks of the Cretaceous southern Gunbarrel Basin, and the underlying Neoproterozoic to Late Devonian southern Officer Basin, Western Australia. The palynomorph assemblages recovered from the Mulga Rocks deposits most closely resemble the Middle Nothofagidites asperus Zone equivalent of the Murray Basin. Many of the species recovered, and the abundance and diversity at which they are present, are considerably different from most of the southeastern Australian palynoassemblages of similar age. Common in the assemblages are species belonging to Nothofagus, Casuarinaceae, Myrtaceae and Picrodendraceae. Proteaceous species are diverse, with Banksia affiliates being prominent. Of most significance are assemblages dominated by Myrtaceidites species, which also contain affiliates of Petrophile and Xylomelum that occur in modern heathland, woodland and dry sclerophyll forests. The prominence of these taxa, and their co-occurrence, suggests that sclerophylly, at present linked closely with xeromorphy and now ubiquitous in the vegetation of Western Australia, was present in the late Eocene of southern Australia and suggests that at that time this trait may have been more prevalent than previously interpreted.

Charlotte Mack [ and Lynne Milne [], Department of Applied Geology, Curtin University of Technology, GPO Box U1987, Perth, WA 6845, Australia. Received 4.7.2014; revised 11.2.2015; accepted 19.2.2015.  相似文献   

20.
When I was a child Reed and masts were erecting by the seashore And I, while lying down there, Failed to tell the difference among them, Since all of them ascended to the sky over my head. Yehuda Amichai. “When I Was a Child”  相似文献   

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