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1.
The comparison of each of the 393 nuclear-encoded human mitochondrial proteins annotated in the SwissProt databank with 256,953 proteins from 94 prokaryote species showed that two thirds of the mitochondrial proteome were homologous with prokaryotic proteins, whereas one third was not. Prokaryotic mitochondrial proteins differ markedly from eukaryotic proteins, particularly in regard to their size, localization, function, and mitochondrial-targeting N-terminal sequence. Remarkably, the majority of nuclear genes implicated in respiratory chain mitochondrial diseases were found to be of prokaryotic ancestry. Our study indicates that the investigation of the co-evolution of eukaryotic and prokaryotic mitochondrial proteins should lead to a better understanding of mitochondrial diseases.  相似文献   

2.
A new species of Hyaenidae, Hyaenictitherium minimum, is described in the carnivore fauna of the Late Miocene layers of Toros-Menalla (Chad). Its size is similar to that of a jackal and it had probably a similar ecological niche. It is found in several fossil-bearing localities of this area. The genus Hyaenictitherium is known from the early Late Miocene in Eurasia from China to Spain; the Chadian material is, perhaps with some specimens from Sahabi and Lothagam, the earliest occurrence of the genus in Africa. It results certainly from Eurasian migration, which will have to be taken into account for the analysis of the bulk of the fauna. To cite this article: L. de Bonis et al., C. R. Palevol 4 (2005).  相似文献   

3.
Sanitheres are enigmatic small suoids with bunoselenodont cheek teeth and a tendency for complication of the premolars by polycuspy and polycristy. Until a few years ago virtually nothing was known about their anterior dentition, but recent discoveries in Greece, Kenya and Namibia have thrown light on their incisor and canine morphology, and reveals among other things that the canines are highly sexually dimorphic, and the dm/1 is replaced by a p/1. Material from Kipsaraman, Kenya, collected between 1997 and 2003, consists of parts of mandibles and many isolated teeth, including elements of the deciduous dentition, a significant proportion of which are unworn. These new finds confirm the aberrant nature of the sanithere dentition within a suoid framework, and support their classification as a family separate from Suidae and Palaeochoeridae (= Old World Tayassuidae).

Résumé

Les sanithères sont de petits Suoïdes aux dents jugales bunosélénodontes avec des prémolaires qui présentent une tendance à la multiplication des cuspides et des crêtes (“polycuspidie” et la “polycristie”). Jusqu’à récemment, on ne connaissait rien sur la morphologie de leur dentition antérieure, mais des découvertes récentes réalisées en Grèce, au Kenya et en Namibie, lèvent le voile sur la morphologie de leurs incisives et de leur canine. Ainsi, il apparaît que les canines sont très dimorphes et que la dm/1 inférieure est remplacée par une p/1. Le matériel de Kipsaraman au Kenya, récolté entre 1997 et 2003, consiste en des fragments de mandibules et de nombreuses dents isolées, dont des dents déciduales, qui pour la plus grande part ne sont pas usées. Ces nouveaux fossiles confirment la nature aberrante de la dentition des sanithères au sein des Suoidea, et supporte leur classification dans une famille distincte des Suidae, et des Palaeochoeridae (= Tayassuidae de l’Ancien Monde).  相似文献   

4.
Two new and the only known extinct seahorse species Hippocampus sarmaticus and Hippocampus slovenicus are described from the Middle Miocene beds (Lower Sarmatian) in Slovenia, representing the oldest known fossil record of seahorses. Hippocampus sarmaticus was most similar to the extant seahorse species Hippocampus trimaculatus, while H. slovenicus can be most easily compared to the extant pygmy seahorses H. bargibanti, H. denise, and H. colemani. These Sarmatian seahorses lived among seagrasses and macroalgae in the temperate shallow costal waters of the western part of the Central Paratethys Sea.  相似文献   

5.
New anthracotheriid remains, discovered by the H-GSP in well-dated localities from the Potwar plateau in the North of Pakistan, between 10.4 and 8.6 Ma, are described and attributed to Merycopotamus medioximus nov. sp. This new species displays an intermediate morphology between the older M. pusillus and the more recent M. dissimilis. These results permit to emend the Merycopotamus diagnosis. To cite this article: F. Lihoreau et al., C. R. Palevol 3 (2004).

Résumé

Une nouvelle espèce d'Anthracotheriidae, Merycopotamus medioximus nov. sp. du Miocène récent du plateau du Potwar, Pakistan. Des restes d'Anthracotheriidae, découverts par le H-GSP dans des localités bien datées du plateau du Potwar, au Nord du Pakistan, entre 10,4 et 8,6 Ma, sont décrits et attribués à Merycopotamus medioximus nov. sp. Cette nouvelle espèce possède une morphologie intermédiaire entre M. pusillus, espèce plus ancienne, et M. dissimilis, plus récente. Ces résultats permettent en outre d'émender la diagnose du genre Merycopotamus. Pour citer cet article : F. Lihoreau et al., C. R. Palevol 3 (2004).  相似文献   

6.
Study of undescribed material from Dor-El-Talha (Libya, Upper Eocene) reveals the existence of at least three different crocodilian taxa at this locality: a gavialid, a tomistomine and a mesosuchian represented by just one amphicoelous vertebra. Most of this material is fragmentary and it includes mainly fragments of snouts and lower jaws. The crocodilian fauna from this locality shows similarities with that from the contemporaneous El Fayum locality (Egypt).

Résumé

L’étude du matériel inédit provenant de Dor-El-Talha (Libye, Éocène supérieur) indique l’existence d’au moins trois taxons différents de crocodiliens : un gavialidé, un tomistomine et un mésosuchien représenté par une seule vertèbre amphicoele. La plupart de ces matériaux est fragmentaire et elle comprend principalement des fragments de museaux et mandibules. La faune crocodilienne de ce gisement montre des ressemblances avec celle provenant du gisement contemporain du Fayum (Egypte).  相似文献   

7.
A mandible fragment of a medium-sized creodont mammal representing a new species of Apterodon, A. intermedius has been discovered in a open cast mine near Leipzig (Germany), dated Late Ruppelian (MP22). For the first time an Apterodon species is well dated in Europe. The dental wear of molars is investigated under SEM. It looks like those described extant carnivores known as preferential flesh eaters. The new specimen together other mammal species questions possible migration ways from Africa to Europe, between the upper Eocene and lower Oligocene.  相似文献   

8.
The discovery of new material in Late Pleistocene levels at Bolomor Cave (Valencia, Spain) raises some questions about the presence of the most ancient record of Hemitragus cedrensis in the peninsula, and its dispersal out of Provence. The morphology and dimensions of some lower teeth confirm the identification of H. aff. cedrensis. Moreover, it presents strong similarities, both morphological and metrical, with the specimens from Caune de l’Arago and bau de l’Aubesier (end of OIS 7 to OIS 5e) rather than with the population from the eponymous locality. The data suggest a dispersal event out of Provence towards the Iberian Peninsula during the Eemian. This dispersal was not stopped by natural barriers such as large rivers, or mountains. The results presented here confirm the biochronological interest of the genus Hemitragus for the Late Pleistocene in Mediterranean Europe.  相似文献   

9.
A finely preserved skull with mandible and teeth associated, from the Latest Miocene beds (ca. 6 Ma) of the Pisco Formation, Sud-Sacaco, Peru, represents a new physeteroid genus and species, Acrophyseter deinodon. This moderate size sperm whale is characterized, among others, by: the short rostrum, the mandible distinctly curved upwards, large teeth very close together (12 on each upper tooth row and 13 on each lower tooth row), the lateral margin of the maxilla along the rostrum base much lower than the orbit roof, a wide supracranial basin dorsally overhanging the right orbit and limited to the cranium and a large temporal fossa dorsomedially elevated. A preliminary cladistic analysis provides a phylogenetic position of Acrophyseter nested within the stem-Physeteroidea, more basal than the clade Kogiidae + Physeteridae. The morphology of the oral apparatus and of the temporal fossa suggests that Acrophyseter was able to feed on large preys.  相似文献   

10.
This paper reports a new species of ancient badger – Meles iberica n. sp. – discovered at the Fonelas P-1 Plio-Pleistocene site (Cuenca de Guadix, Granada, Spain). The anatomical features of its fossils, which identify it as a new species of Meles, include: the great robustness and small size of the specimens found, orbits nearly closed by well-developed zygomatic processes of the frontal bone, very small and rounded infraorbital foramens that open above the fourth upper premolar metacone, upper carnassial teeth with a concave linguodistal outline, the reduction of the talon of the first upper molar, a very deep masseteric fossa, whose anterior margin reaches the mesial limit of the second lower molar, an extensive horizontal platform at the base of this fossa, and a very long and narrow angular apophysis. This species is the most ancient of the genus recorded for the Iberian Peninsula.  相似文献   

11.
Fossil teeth and bones of aardvarks are relatively common at Langebaanweg, an Early Pliocene site in western Cape Province, South Africa. The remains are compatible in size and most details of morphology to extant Orycteropus afer, and are the earliest fossils attributed to this species. Other Late Miocene to Early Pliocene localities in Africa have yielded smaller species of aardvarks, suggesting that the extant lineage evolved in southern Africa. Morphologically the genus Orycteropus has been remarkably conservative since at least the Early Miocene but it witnessed an overall increase in size through the Neogene. The species O. afer has been morphometrically stable since the Early Pliocene. These observations indicate that the evolutionary process in aardvarks is extremely bradytelic. To cite this article: M. Pickford, C. R. Palevol 4 (2005).  相似文献   

12.
The presence of a large hyaenoid (Hiperhyaena sic leakeyi) from the Late Miocene (Vallesian equivalent) deposits at Nakali, Kenya, was first recorded in 1974, but the fossil on which the announcement was based was not described or figured, nor was a type specimen or type species nominated. The generic and specific names are thus nomina nuda. Howell and Petter (1985) described Hyperhyaena leakeyi, and credited the generic and specific names alternatively to Aguirre and Leakey (1974) and Aguirre and Crusafont in 1974 (the latter paper was never published). Howell and Petter are in fact the authors of both the generic and the specific names. Later in the same paper, Howell and Petter (1985) rejected the name Hyperhyaena and classified the species leakeyi in Allohyaena (Dinocrocuta). The purpose of this paper is to provide more information about the fossil and to discuss its relationships to other percrocutids. It is concluded that it belongs to the genus Percrocuta Kretzoi, 1938, being morphologically similar to the type species Percrocuta carnifex (Pilgrim, 1913) from the Siwaliks of Pakistan.  相似文献   

13.
A new genus and species of troglobitic buthid scorpion are described on the basis of a single specimen collected in Brazil. This is the first cavernicolous scorpion ever found in Brazil, and only the second to be found in South America. Some considerations on troglobitic scorpions are proposed.  相似文献   

14.
The discovery of a propotamochoerine suid with unique features of the dentition and skull led to the naming of Molarochoerus yuanmouensis Liu & Pan [6]. Further study of the material reveals that this species was better adapted than Sus scrofa for the ‘rooting’ behaviour and that its dentition has morphological features indicating that it was eating hard food items. The posterior premolars are completely molarised, hence the generic name, the first time that any suid has been shown to possess almost perfectly molariform P4/s and p/4s. In lateral view the curvature of the occlusal surface of the upper cheek teeth is convex ventrally, the opposite of the usual situation in suids. The origins of the rostral musculature are exceptionally well developed, and the nasal bones are much more robust than is usually the case in Suinae, indicating powerful musculature and fortified osseous structures presumably for ‘rooting’ in hard ground or for extended periods of time. The masseteric musculature appears to have been more massive than it is in Sus, Microstonyx and Propotamochoerus. To cite this article: M. Pickford et al., C. R. Palevol 3 (2004).

Résumé

Systématique et morphologie fonctionnelle de Molarochoerus yuanmouensis (Suidae, Mammalia) du Miocène supérieur de Yunnan, Chine. La découverte d”un Suidae Propotamochoerini présentant des caractères dentaires et crâniens uniques a conduit à la création de Molarochoerus yuanmouensis Liu & Pan [6]. Une étude du matériel montre que cette espèce était bien mieux adaptée au fouissage que Sus scrofa. Par ailleurs, les caractères morphologiques de sa dentition indiquent qu'il se nourrissait d'aliments coriaces. Les prémolaires postérieures sont complètement molarisées, d'où le nom générique, et c'est la première fois qu'un Suidae présente des P4 supérieures et inférieures presque parfaitement molariformes. En vue latérale, la courbure de la surface occlusale des dents jugales supérieures est convexe ventralement, différant ainsi de la morphologie classique des Suidae. La musculature rostrale est exceptionnellement bien développée et les os nasaux sont beaucoup plus robustes que chez les autres Suinae, suggérant des structures musculaires et osseuses puissantes, probablement liées au fouissage, soit dans des sols, soit sur une longue durée. Les muscles massétériens sont plus puissants que dans les genres Sus, Microstonyx et Propotamochoerus. Pour citer cet article : M. Pickford et al., C. R. Palevol 3 (2004).  相似文献   

15.
Conohyus indicus is a poorly known tetraconodont suid from the summit of the Lower Siwaliks and the base of the Middle Siwaliks of the Indian Subcontinent. Even though it was first recorded well over a century ago, only 13 specimens have since been described in the literature, consisting of isolated teeth and incomplete mandible and maxilla fragments. We here describe another fragmentary mandible from the Ramnagar Member (uppermost Middle Miocene to basal Late Miocene) of the Siwalik Group, which contains the left canine lacking its tip, the alveolus of P/1 and the left P/2 – P/3 and right P/3 - M/1. The new specimen, albeit incomplete,provides interesting information about the anterior parts of the jaw and throws light on the systematic position of the species as well as the recently described species Conohyus thailandicus from Thailand.  相似文献   

16.
A new species of Deinsdorfia is defined using new material coming from the karstic fissure infilling of Almenara-Casablanca 4 (Castelló, Spain), which shows important differences with the rest of the previously known species of the genus. The definition of a new species is supported by the characters found in extra material coming from the localities of Valdeganga, in the Albacete Province (Spain). The stratigraphical occurrence of this genus of pigmented-toothed shrews reinforces the idea of the Iberian Peninsula as a sink area during the Pliocene, where some Central-European soricids expanded their distribution. Most of those migrations or distributional expansions coincide with moments of climatic changes in the northern hemisphere.  相似文献   

17.
The site of Mansourah (Constantine, Algeria) had yielded to the early authors, and more recently to the late G. Laplace, a lithic industry associated with a fauna of large Mammals, which looks contemporaneous with that of Aïn Hanech, although it is well-distinct ecologically, and might even be slightly older. The lithic assemblage is completely devoid of any bifacial artefact or cleaver and can only be referred to the Oldowan. Thus, the Mansourah site documents a very early human occupation of North Africa, and perhaps one of the earliest. To cite this article: Y. Chaid-Saoudi et al., C. R. Palevol 5 (2006).  相似文献   

18.
19.
For the first time unequivocal fossil remains of a green toad (Bufo viridis s.l.) are described in the Iberian Peninsula. The fossils come from the Cueva Victoria site, a late Early Pleistocene (ca. 1.1–1.2 Ma) karstic filling in semi-arid southeastern Spain (Murcia region). By extension, other remains from two other Early Pleistocene Spanish localities, Barranco León D (ca. 1.3 Ma) and Almenara-Casablanca 3 (ca. 1.1 Ma), are cautiously attributed to the group B. viridis. The B. viridis group was previously reported with some uncertainty to the west of its current distribution area in Western Europe (Spain and France) in the Pliocene (Bufo cf. viridis) and less probably in the Early Miocene (Bufo aff. viridis). Since no osteological differences have been established between the recently described extant species of B. viridis s.l. (e.g. Bufo balearicus, Bufo siculus, Bufo boulengeri, B. viridis sensu stricto and Bufo variabilis) no precise palaeobiogeographical relationships can be drawn for the Spanish fossils. However, the occurrence of a third species of bufonid toad during the Pleistocene in the South of the Iberian Peninsula raises some interesting ecological questions in relation to the local disappearance of the green toad, which can be hypothetically linked to the intensification of the Pleistocene glacial/interglacial climate dynamic or to probable competition with another toad, Bufo calamita.  相似文献   

20.
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