scholarly journals New information about the skull and dentary of the Miocene platypus Obdurodon dicksoni , and a discussion of ornithorhynchid relationships

1998 ◽  
Vol 353 (1372) ◽  
pp. 1063-1079 ◽  
Author(s):  
A. M. Musser ◽  
M. Archer

A reconstruction of the skull, dentary and dentition of the middle Miocene ornithorhynchid Obdurodon dicksoni has been made possible by acquisition of nearly complete cranial and dental material. Access to new anatomical work on the living platypus, Ornithorhynchus anatinus , and the present comparative study of the cranial foramina of Ob. dicksoni and Or. anatinus have provided new insights into the evolution of the ornithorhynchid skull. The hypertrophied bill in Ob. dicksoni is seen here as possibly apomorphic, although evidence from ontogenetic studies of Or. anatinus suggests that the basic form of the bill in Ob. dicksoni (where the rostral crura meet at the midline) may be ancestral to the form of the bill in Or. anatinus (where the rostral crura meet at the midline in the embryonic platypus but diverge in the adult). Differences in the relative positions of cranial structures, and in the relationships of certain cranial foramina, indicate that the cranium may have become secondarily shortened in Or. anatinus , possibly evolving from a more elongate skull type such as that of Ob. dicksoni . The plesiomorphic dentary of Ob. dicksoni , with well–developed coronoid and angular processes, contrasts with the dentary of Or. anatinus , in which the processes are almost vestigial, as well as with the dentary of the late Oligocene, congeneric Ob. insignis , in which the angular process appears to be reduced (the coronoid process is missing). In this regard the dentary of Ob. insignis seems to be morphologically closer to Or. anatinus than is the dentary of the younger Ob. dicksoni . Phylogenetic conclusions differ from previous analyses in viewing the northern Australian Ob. dicksoni as possibly derived in possessing a hypertrophied bill and dorsoventrally flattened skull and dentary, perhaps being a specialized branch of the Obdurodon line rather than ancestral to species of Ornithorhynchus . The presence of functional teeth and the robust, flattened skull and dentary in Ob. dicksoni argue for differences in diet and lifestyle between this extinct ornithorhynchid and the living Ornithorhynchus .

Author(s):  
A. Rosalie David

The mummy of Natsef-Amun, a priest in the Temple of Amun at Karnak (ca.1000 BC), was purchased for the Leeds Philosophical Society, England, in 1823. Members of the Society unwrapped the mummy and carried out one of the earliest multi-disciplinary mummy investigations in 1824. In recent years, the Manchester Mummy Project undertook a new scientific study of this mummy. The range of techniques they employed included radiology, paleoodontology, endoscopy, histology, immunohistochemistry, paleoserology, aDNA identification, and scientific facial reconstruction. This rare opportunity to compare the methodology and results of an early investigation with those of a contemporary study will be considered in this paper which will also demonstrate how scientific studies can add new information to historical and archaeological data about lifestyle, diseases, death and funerary procedures associated with a priest who lived at a tumultuous period of Egyptian history.


2020 ◽  
Vol 218 ◽  
pp. 103366 ◽  
Author(s):  
Ali Ihsan Karayigit ◽  
Mustafa Atalay ◽  
Rıza Görkem Oskay ◽  
Patricia Córdoba ◽  
Xavier Querol ◽  
...  

1984 ◽  
Vol 3 (2) ◽  
pp. 73-94 ◽  
Author(s):  
William A. S. Sarjeant

Abstract. The type material of six dinoflagellate cyst species from the Late Oligocene to Middle Miocene of northwest Germany, described originally by Gerlach (1961), is reillustrated and redescribed. It is shown to include representatives of nine species. Areosphaeridium (ex: Baltisphaeridium) pectiniforme is found to be a senior synonym of Areosphaeridium multicornutum Eaton. Systematophora placacantha is considered to be a senior synonym of Cleistosphaeridium (ex: Baltisphaeridium) panniforme (Gerlach). The new combination Rhynchodiniopsis tenuitabulata (Gerlarch) is proposed. Revised diagnoses for these three species and for Leptodinium membranigerum (Gerlach), Achomosphaera triangulata (Gerlach) and Lejeunecysta hyalina (Gerlach) are proposed. The morphology of a form described here for the first time, and tentatively attributed to Phthanoperidinium, is considered perhaps to imply a separate origin for the Phthanoperidiniaceae: for that reason familial, rather than tribal, rank is preferred for that group. The stratigraphical ranges of the nine species here recognised and of two others of Gerlach’s species redescribed in earlier papers are detailed; elimination of misattributed forms means that these ranges are shorter than the published literature suggests.


The general geology of the New Hebrides is summarized in terms of three volcanic and two main sedimentary episodes. Calc-alkaline volcanics ol the first episode occur on the western islands and accumulated mainly on the submarine slopes below small reef-fringed volcanic islands in Late Oligocene to Middle Miocene times. During the Late Miocene and Early Pliocene wholly submarine tholeiitic or high-Al volcanics accumulated in the eastern and southern part of the New Hebrides while calcareous sediments were forming in the western islands. During the third volcanic phase, of Pliocene to Recent age, regional uplift has led to most of the volcanics being subaerial while extensive flights of limestone terraces occur round the older islands. In consequence the land area of the New Hebrides has increased rapidly during Quaternary times. The landforms produced are briefly described.


2021 ◽  
Vol 69 (Suppl.1) ◽  
pp. 35-50
Author(s):  
Claudia-J. Del Río ◽  
Sergio Martínez

Introduction: Scutelliforms were diverse and widespread in shallow marine environments during Neogene times in South America. Nevertheless, they have almost never been used as biostratigraphic tools. Objective: To provide a refined stratigraphic frame useful for calibrating temporal dimensions of scutelliform diversity from Argentina and Uruguay and its correlation with the molluscan assemblages previously proposed. Methods: A detailed survey of their geographic and stratigraphic provenance was carried out. We revised both the bibliography and collections (institutional and from our own field work). Results: The group is represented by 14 species belonging to six genera, and four assemblages were identified. Numerical dates of the Neogene marine rocks obtained recently allowed their placement in a chronological scheme: “Iheringiella” sp. A is restricted to the late Oligocene, the genera Camachoaster and “Eoscutella” and the species Monophoraster telfordi to the early Miocene, Abertella gualichensis and Abertella miskellyi to the middle Miocene, and Monophoraster duboisi, Amplaster coloniensis and Amplaster ellipticus to the late Miocene. Non-lunulate scutelliforms are not restricted to the late Oligocene as previously supposed. The oldest occurrence of the genus Monophoraster corresponds to the early Miocene, and along with Iheringiella are long-living taxa that embrace the 25.3 Ma-18.1 Ma (Iheringiella patagonensis) and approximately 15 Ma-6.48 Ma (Monophoraster darwini) intervals. The presence of Iheringiella in the early Miocene of northeastern Patagonia is corroborated, reaching there its northernmost distribution. Monophoraster darwini has a temporal range from the late Miocene (where it was previously thought to be restricted) back to the middle Miocene, since this is the species yielded in the well-known and discussed “Monophoraster and Venericor Beds”. Conclusions: The Paleogene-Neogene scutelliforms of Argentina and Uruguay range from the late Oligocene to the late Miocene. There is a good correspondence among the numerical ages, molluscan biozones and scutelliform assemblages.


2015 ◽  
Vol 5 (6) ◽  
pp. 116-124
Author(s):  
Md. Zahidul Islam

Most of the commercial banks in Bangladesh arrange different training programs for adapting their existing human resources to their jobs and also updating new information or techniques and reshaping their knowledge. The purpose of the paper is to discover the level of efficiency of training among different commercial banks in Bangladesh. The study is mostly plunked on primary data that were composed from 100 employees as sample of different banks in Dhaka. Some statistical tools like mean standard deviation, hypothesis etc. were used for analyzing data in this paper. The study reveals that most of the commercial banks arrange initial training and in house training but they do not arrange mid level or advanced training as well as off the job training. Most of the banks in Bangladesh do not frequently arrange training programs. The average level of efficiency of training of all banks is 77.08%. The levels of efficiency of training from higher to lower level are as follows: DBBL, BBL, IBBL, TBL and ABL.


PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3458 ◽  
Author(s):  
Adam M. Yates

New records of the Oligo–Miocene mekosuchine crocodylian, Baru, from Queensland and the Northern Territory are described. Baru wickeni and Baru darrowi are accepted as valid species in the genus and their diagnoses are revised. Both species are present in Queensland and the Northern Territory but are restricted in time, with B. wickeni known from the late Oligocene and B. darrowi from the middle Miocene. The broad geographic distributions and restricted time spans of these species indicate that this genus is useful for biochronology. The record of B. wickeni from the Pwerte Marnte Marnte Local Fauna in the Northern Territory establishes that the species inhabited the north-western margin of the Lake Eyre Basin (LEB) drainage system. More southerly Oligo–Miocene sites in the LEB contain only one crocodylian species, Australosuchus clarkae. The Pwerte Marnte Marnte occurrence of B. wickeni indicates that the separation of Baru and Australosuchus did not correspond with the boundaries of drainage basins and that palaeolatitude was a more likely segregating factor.


2019 ◽  
Vol 46 (2) ◽  
pp. 368
Author(s):  
Gabriela Ines Schmidt ◽  
Esperanza Cerdeño ◽  
Santiago Hernández Del Pino

In this contribution we present new specimens of Litopterna recovered during the last decade in Quebrada Fiera (Mendoza Province, Argentina), whose fossiliferous sediments, currently recognized as the base of Agua de la Piedra Formation, are assignable to Late Oligocene (Deseadan South American Land Mammal Age). Two remains mentioned in the first publication on this locality were neither detailed nor described, and they have not been located in the corresponding repository. The new material consists of postcranial fragmentary remains (astragali, calcaneum, and metapodials) of Macraucheniidae (Cramaucheniinae) and an incomplete upper molar (M3) of Proterotheriidae (Proterotheriinae). These few remains of litopterns contrast with the abundance of notoungulates at Quebrada Fiera. A comparative study was carried out with material from Patagonia (Argentina) and taxa recorded in Bolivia and Peru for the same temporal interval. The specimens of Cramaucheniinae are assigned to Coniopternium andinum and the molar of Proterotheriinae to cf. Lambdaconus suinus. This contribution allows us to extend the geographical range of Coniopternium, filling the gap between the Patagonian and lower latitude localities (Bolivia and Peru) in which this genus was found. The record of L. suinus in Quebrada Fiera expands the geographical range of this species outside from Patagonia.


2010 ◽  
Vol 6 (4) ◽  
pp. 461-473 ◽  
Author(s):  
P. Sepulchre ◽  
D. Jolly ◽  
S. Ducrocq ◽  
Y. Chaimanee ◽  
J.-J. Jaeger ◽  
...  

Abstract. Only few well-dated records document the evolution of Southeast Asian paleoenvironments during the Cenozoic. Here we analyse continental pollen assemblages from Late Oligocene and Miocene fossil sites of Thailand. In agreement with previous studies, palynoflora from the Oligocene suggests warm temperate forested habitats at 24–26 Ma, whereas Middle Miocene assemblages are made of thermophilous taxa. This change can be linked to the major climate reorganization that brought warmer and wetter conditions over Southeast Asia around 22 Ma. This study also provides the first submillional records from the Middle Miocene of Thailand. Thirteen samples of lignite layers from the sivaladapid-bearing Mae Moh site, dated between 13.3 and 13.1 Ma, and six samples from the hominoid-bearing Chiang Muan deposit, dated between 12.4 and 12.2 Ma, document oscillations between tropical woodlands and grasslands in northern Thailand. These pollen records likely reflect climate variations linked to insolation variations. Late Miocene palynological assemblages from Khorat, northeastern Thailand, document fluviolacustrine paleoenvironments alternatively covered by thermophilous trees and grasslands. These records show that both sivaladapids and early hominoids from Thailand have evolved in tropical environments with high variability in the vegetation cover.


2015 ◽  
Vol 24 ◽  
pp. 383-397 ◽  
Author(s):  
Ferdi DEMİRTAŞ ◽  
Mustafa BOZCU ◽  
Erdal KOŞUN ◽  
Mehmet Serkan AKKİRAZ

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