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Were all Devonian seeds cupulate? A reinvestigation of Pseudosporogonites Hallei, Xenotheca Bertrandii and Aglosperma spp.
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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.
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Were ancient foxes far more carnivorous than recent ones? Carnassial morphological evidence
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Crown shape variation of the first lower molar in the arctic (Vulpes lagopus) and red foxes (Vulpes vulpes) was analyzed using five groups of morphotypes. Carnassial morphologies were compared between the species and between spatially and temporally distant populations: one Late Pleistocene (n = 45) and seven modern populations of the arctic fox (n = 259), and one Late Pleistocene (n = 35) and eight modern populations of the red fox (n = 606). The dentition of Holocene red foxes had larger morphotype variability than that of arctic foxes. The lower carnassials of the red fox kept have some primitive characters (additional cusps and stylids, complex shape of transverse cristid), whereas the first lower molars of the arctic fox have undergone crown shape simplification, with the occlusal part of the tooth undergoing a more pronounced adaptation to a more carnivorous diet. From the Late Pleistocene of Belgium to the present days, the arctic fox’s crown shape has been simplified and some primitive characters have disappeared. In the red fox chronological changes in the morphology of the lower carnassials were not clearly identified. The phyletic tree based on morphotype carnassial characteristics indicated the distinctiveness of both foxes: in the arctic fox line, the ancient population from Belgium and recent Greenland made separate branches, whereas in the red foxes the ancient population from Belgium was most similar to modern red foxes from Belgium and Italy.
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RBINS Staff Publications 2020
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Were bears or lions involved in salmon accumulation in the Middle Palaeolithic of the Caucasus? An isotopic investigation in Kudaro 3 cave
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Bone fragments of large anadromous salmon in the Middle Palaeolithic archaeological layers of Kudaro 3 cave (Caucasus) suggested fish consumption by archaic Hominins, such as Neandertals. However, large carnivores such as Asiatic cave bears (Ursus kudarensis) and cave lions (Panthera spelaea) were also found in the cave and could have been responsible for such an accumulation. The diet of these carnivores was evaluated using carbon, nitrogen and sulphur isotopes in faunal bone collagen. The results suggest that anadromous fish were neither part of the diet of either cave bear (vegetarian) or cave lion (predators of herbivores from arid areas) and therefore provide indirect support to the idea that Middle Palaeolithic Hominins, probably Neandertals, were able to consume fish when it was available.
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West African Manatee Trichechus senegalensis (LINK, 1795) in the Estuary of the Congo River (Democratic Republic of the Congo): Review and Update
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RBINS Staff Publications 2017
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What are Ostracoda? A cladistic analysis of the extant superfamilies of the subclasses Myodocopa and Podocopa (Ostracoda: Crustacea). In: KOENEMANN, S & R.A. JENNER (Eds.), Arthropoda and crustacean phylogeny
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What are Ostracoda? A cladistic analysis of the extant superfamilies of the subclasses Myodocopa and Podocopa (Ostracoda: Crustacea)
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What are Ostracoda? A cladistic analysis of the extant superfamilies of the subclasses Myodocopa and Podocopa (Crustacea: Ostracoda)
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What can molecular data from ostracods tell us? 14th International German Ostracodologists’ Meeting
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What do we know today about the Middle Palaeolithic of Spy?
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What is inside this pit? Micro- and macrofaunal investigations at Chalcolithic and Early Bronze Age Ovçular Tepesi (Nakhchivan, Azerbaijan )
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The site of Ovçular Tepesi is located in the southern Caucasus (Nakhchivan Autonomous Republic). Two main archaeological phases were recognised at the settlement, namely Late Chalcolithic and Early Bronze Age. More than 1160 litres of soil samples from pits and circular stone structures belonging to the different occupation layers were processed by flotation and analysed. This paper focuses on the zoological finds from these samples, in particular the remains of fish, large mammals and micromammals, in order to determine the function of the pits and structures. Moreover, the material gives an insight into the animal economy, hunting and fishing practices of the inhabitants, as well as the local environment. Thus far, it could not be established whether the differences detected in the species composition between the phases are related to chronology alone or if other factors, such as sample sizes and type of deposits, also played a role. Fish bones were very frequent at the site with cyprinids dominating. Among the large mammals, domestic animals were the most frequent while hunted species were rare. Sheep and goat herding seems to have been the principal subsistence strategy at this site. The small mammal community is composed of synanthropic taxa and, as a consequence, the species diversity was very low (six taxa). House mouse was the most abundant in each feature on the site.
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