-
Possible evidence of mammoth hunting at the Neanderthal site of Spy (Belgium)
-
Spy, a Belgian cave site famous for its Neanderthal remains, contains a wide spectrum of Pleistocene species. Horse, cave hyena, woolly mammoth, woolly rhinoceros and reindeer are the primary taxa. The Spy cave was used alternately by prehistoric humans and Pleistocene carnivores. This study considers whether prehistoric humans or carnivores are responsible for the large number of mammoth remains at the site. It is argued, on the basis of the frequency distribution of the skeletal elements of the mammoth, the age distribution of the mammoth molars, and the diet of the large carnivores and of the prehistoric humans, that the mammoth assemblage of Spy accumulated at the site through the activities of prehistoric humans. On the basis of AMS dates, the stratigraphic position of a number of mammoth molars and the absence of red ochre on the mammoth molars, it was concluded that these prehistoric humans were Neanderthals rather than Anatomically Modern Humans.
Located in
Library
/
RBINS Staff Publications
-
Were all Devonian seeds cupulate? A reinvestigation of Pseudosporogonites Hallei, Xenotheca Bertrandii and Aglosperma spp.
-
Premise of research. Although the most comprehensively known Devonian seeds were borne in a “telomic” cupule, those of some species have been postulated as being borne terminally on naked axes lacking a cupule. Uncertainty remains as to whether such seeds were shed from a cupule before preservation. We reinvestigate the Upper Devonian fossils Pseudosporogonites hallei and Xenotheca bertrandii from Belgium and the similar ovules Aglosperma quadrapartita and Aglosperma avonensis from Britain and Aglosperma sp. from North America to consider their structure and organization and to determine whether they were cupulate. Methodology. Compressions/adpressions of X. bertrandii and Pseudosporogonites from Belgium and A. quadrapartita and A. avonensis from the United Kingdom, as well as Anglosperma sp. from Pennsylvania, were prepared, mainly by dégagement. Observation and photography were carried out using crossed polarizing filters. Pivotal results. Pseudosporogonites hallei, X. bertrandii, and A. quadrapartita comprise single ovules borne within small, radially symmetrical, uniovulate cupules. Integuments are entire at the chalaza but form flattened lobes distally. While a cupule is unknown in A. avonensis, its comparable integument morphology suggests that it was shed from a uniovulate cupule. Although the species are distinct from each other, their similarities show that they are closely related and belong to a single genus, for which the name Pseudosporogonites has priority. We emend P. hallei in light of our findings and erect the combinations P. bertrandii (Stockmans) C. Prestianni, J. Hilton et W. Cressler, P. quadrapartitus (J. Hilton et D. Edwards) C. Prestianni, J. Hilton et W. Cressler, and P. avonensis (J. Hilton) C. Prestianni, J. Hilton et W. Cressler. Conclusions. The uniovulate cupule in Pseudosporogonites is distinct from multiovulate telomic cupules of other Devonian seeds and expands the phenotypic diversity seen during the earliest phase of seed plant radiation, which was geologically instantaneous. Hydrasperman pollination in all proven Devonian seeds demonstrates evolution from a common ancestor, but finding morphological intermediates between seed and free-sporing plants remains a significant challenge to evolutionary plant biology.
Located in
Library
/
RBINS Staff Publications
-
A Middle Devonian Callixylon (Archaeopteridales) from Ronquières, Belgium
-
A permineralized Callixylon trunk is reported from Ronquières, a mid to late Givetian (Middle Devonian) locality from Belgium. The specimen consists of an 80 cm long trunk adpression whose central area is preserved as a pyrite permineralization. The pyritized area is composed of a eustele surrounded by secondary xylem. Tracheids show radially aligned groups of pits separated by unpitted regions on the radial walls of tracheids. The specimen belongs to a group of species characterized by a predominance of uniseriate rays and the lack of ray tracheids. This Callixylon specimen is one of the earliest representatives of the genus. It coexists at the locality with large cladoxylopsids and provides direct evidence that the tree habit had evolved in the archaeopteridalean progymnosperms by the Givetian.
Located in
Library
/
RBINS Staff Publications
-
A Simple Type of Wood in Two Early Devonian Plants
-
Located in
Library
/
RBINS Staff Publications
-
Diverse assemblages of Mid Devonian megaspores from Libya.
-
A restudy of Devonian palynological assemblages of samples from the A1-69 borehole, drilled in the Ghadamis Basin, western Libya, North Africa has led to the discovery of numerous well-preserved megaspores amongst abundant miospores, rare acritarchs and rare chitinozoans. Thirteen samples from base to top, 1496 ft (456 m) up to 965 ft (294 m), contain the richest Devonian megaspore assemblages from northwestern Gondwana. The section is dated by a rich diverse miospore assemblage indicating the presence of the upper part of the AD pre-Lem Biozone up to the lower part of the TCo Oppel Zone, ranging from a latest Eifelian or earliest Givetian age up to a latest Givetian or an earliest Frasnian age. Seventeen megaspore taxa have been identified. Among them, two new species (Biharisporites lugardonii and Lagenicula milleri) and four new varieties (Corystisporites acutispinosus var. acutispinosus and var. bullatus, Heliotriletes longispinosus var. longispinosus and var. radiatus) are described. One new possible megaspore species is also described: Verruciretusispora labiosa sp. nov. One core sample (1293 ft, 394 m) contains several specimens of very large megaspores (ca. 1 mm), the largest known from Devonian localities (except for one specimen observed in the Givetian from Belgium). Among the 17 megaspore taxa from Libya, 6 are present on the Euramerican Continent. This observation is in accordance with previous palynological conclusions that favour the absence of palaeogeographic barriers between the Euramerican and Gondwanan continents that are suggested to be grouped together in a “Pre-Pangea” land mass.
Located in
Library
/
RBINS Staff Publications
-
Un fossé circulaire de l’âge du Bronze moyen au lieu-dit Champ de la Bruyère
-
Located in
Library
/
RBINS Staff Publications
-
Perturbation of a coastal Tethyan environment during the Paleocene-Eocene thermal maximum in Tunisia (Sidi Nasseur and Wadi Mezaz).
-
Despite the large number of studies on the Paleocene–Eocene thermal maximum (PETM), the knowledge of environmental and biotic responses in shallow marine environments remains quite poor. Benthic foraminiferal assemblages of the Sidi Nasseur and Wadi Mezaz sections in Tunisia were studied quantitatively and the paleoecologic interpretations provide new insights into the complex relationship between PETM global warming and perturbations of shallow marine settings. These sections expose upper Paleocene to lower Eocene shales and marls of the El Haria Formation up to the phosphate layers of the Chouabine Formation underlying the El Garia limestones. The Sidi Nasseur section contains a more complete and expanded Paleocene–Eocene boundary interval compared to Wadi Mezaz, although being truncated at the top. The Wadi Mezaz section contains a more complete post-PETM interval. The studied interval can be subdivided into a sequence of 4 biofacies, representing respectively a latest Paleocene biofacies, two PETM biofacies and one post-PETM Eocene biofacies. The latest Paleocene biofacies 1 consists of numerous calcareous benthic foraminifera (e.g. Anomalinoides midwayensis, Frondicularia aff. phosphatica and various Bulimina and Lenticulina species), abundant noncalcareous taxa (Haplophragmoides) and rare planktic foraminifera, indicating a slightly hypersaline eutrophic inner neritic to coastal environment, regularly interrupted by oxygen deficiency (moderate dysoxia). During the latest Paleocene, this highly productive environment shallowed as indicated by the increasing abundances of A. midwayensis. The variable dominance of non-calcareous agglutinated taxa in biofacies 1 indicates post-mortem dissolution effects. The TOC δ13Corg record reveals a sharp negative excursion, marking the base of the Eocene. In general, the absence of lithologic changes, an increasing sedimentation rate and absence of reworking indicate that the initial part of the PETM is complete and expanded in the Sidi Nasseur section. A sharp faunal turnover coincides with this negative δ13Corg excursion and is characterized by the disappearance or diminution of common Paleocene taxa in this area. During the PETM, benthic foraminifera are less abundant and consist of opportunistic non-calcareous taxa together with deeper dwelling (middle neritic) lagenids and buliminids (biofacies 2 and 3). Planktic foraminifera, dominated by flat-spired Acarinina (mainly A. multicamerata), become more abundant, as observed in many open marine sequences worldwide. All these faunal parameters suggest more stressed probably severe dysoxic sea floor conditions within a transgressive phase during the onset of the PETM. An estimation of the total duration of the Sidi Nasseur PETM interval is difficult to establish, yet the lack of recovery carbon isotope values suggests that the preserved PETM interval reflects only a part of the CIE “core”. The top of the PETM interval is truncated due to local (?) erosion during the early Eocene. The Eocene recovery fauna is mainly composed of Lenticulina and Stainforthia species (biofacies 4), indicating restricted coastal to hyposaline lagoonal eutrophic conditions, distinctly different from earlier environmental conditions.
Located in
Library
/
RBINS Staff Publications
-
Characterization of the Latest Danian Event by means of benthic foraminiferal assemblages along a depth transect at the southern Tethyan margin (Nile Basin, Egypt).
-
The Latest Danian Event (LDE) has been recognized on the southern Tethyan margin (Egypt; Tunisia), and in the Atlantic (Zumaia, Spain) and Pacific Oceans (ODP Site 1209). Based on a supraregional carbon isotope excursion, and a negative shift in oxygen isotopes in the Pacific it has been suggested that the LDE is an early Paleogene transient warming event. So far the environmental effects of the LDE have been observed in few sections and details on its impact and duration are scarce. We present a quantitative study of benthic foraminiferal assemblages retrieved from five sections along a depth transect on the Paleocene southern Tethyan shelf (Nile Basin, Egypt) to assess paleoenvironmental change during the LDE. The lithologic sequences and foraminiferal assemblages indicate that the onset of the LDE is related to widespread shelf dysoxia. The organic-rich laminated marls of lower LDE bed I contain levels devoid of benthic foraminifera. During the later stage of the LDE (dark-gray shales of bed II) the shelf is repopulated by a Neoeponides duwi benthic assemblage, occurring in all sections, initiating a gradual restoration of normal-marine shelf environments. Q-mode and R-mode correspondence analysis assist in the interpretation of the N. duwi assemblage, which is related to disturbed conditions at the sea floor following oxygen depletion and increased organic loading. The sharp lithologic boundary at the base of the LDE suggests that the event coincides with a rapid transgression following a sea-level fall, with an estimated amplitude of ~ 50 m or less. Comparison with the Dan-C2 and ELPE/MPBE, two proposed transient warming episodes preceding and postdating the LDE, shows that the three Paleocene events have several characteristics in common. However, the duration of the LDE (~ 200 kyr) exceeds the estimated duration of the other events, and a sea-level cycle is only reported from the LDE.
Located in
Library
/
RBINS Staff Publications
-
Large-scale glaciation and deglaciation of Antarctica during the Late Eocene: Comment.
-
Peters et al. (2010) present a hypothesis for a late Eocene glaciation, by interpreting an incision surface at Wadi Al-Hitan (Egypt) as indicating a 40+ m fall in eustatic sea levels. We argue that there is no evidence for a major fall in sea level, and that their calibration of the event is unproven.
Located in
Library
/
RBINS Staff Publications
-
Early Paleogene δ13C and δ18O records based on marine ostracodes: implications for the upper Danian succession at Sidi Nasseur (Tunisia) and their application value in paleoceanography
-
Ostracode and other microfossil assemblages from the Tunisian Trough have previously been studied to characterize paleoenvironmental conditions during the late Danian interval. Whereas the preservation of foraminifera is generally not sufficient for stable isotope studies, well preserved ostracodes provide continuous upper Danian stable isotope records (δ13C, 18O) at Sidi Nasseur, W Tunisia. The late Danian is considered to cover a hyperthermal, known as the “Latest Danian Event” (LDE; ~61.75 Ma) or “Top C27n Event” and has been unequivocally identified in benthic foraminiferal isotopes from shelf sediments in Egypt and deep-sea material from the Pacific Ocean. Stratigraphic changes in the isotope ratios of the genus Bairdia reveal a rather scattered record for δ13C lacking any pronounced negative δ13C excursion, probably due to the many factors influencing δ13C in ostracodes like metabo- lism, diet or dissolved inorganic carbon of sea-water. The accompanying δ18O record is less ambiguous showing a shift towards lower values close to the level where the LDE is to be expected, but minimum values are similar to δ18O values at the base and top of the studied sequence. These data suggest that the core of the negative stable isotope excursions of the LDE is lost in the stratigraphic gap at the planktic foraminiferal P3a/P3b and calcareous nannofossil NTp7A/NTp7B subzonal boundaries, so that the LDE could not be unequivocally identified in Tunisia. A cross-plot of δ13C and δ18O of ostracode valves displays distinctive clusters for smooth-shelled taxa like Bairdia and others as well as for ornamented taxa, with the latter group showing substantially lower values for both δ13C and δ18O. This pattern strongly resembles those from early Eocene data from southwestern France and Recent ostracodes from the Iceland Plateau. The offsets suggest substantial differences in life style, food source or isotope fractionation during the calcification process for different shell morphologies in ostracodes.
Located in
Library
/
RBINS Staff Publications
