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1.
Since 1991, several human remains: 5 skulls, 4 mandibles and numerous postcranial fragments have been discovered on the Dmanissi prehistoric open site. It is an exceptional discovery due to the stratigraphical, paleontological and cultural context, which is well known and accurately well dated (Upper Pliocene-Early Pleistocene). Most of the hominids discovered in the level V and VI are dated between 1.81 My (level V) and 1.77 My (level VI) corresponding to a 40,000 years period. The assemblage of fossil human remains is peculiar due to (1) the quality of bone representation (distinct parts of the skeleton are preserved: skull, thorax, upper and lower limbs, belt), (2) the high degree of bone preservation (skulls and long bones are entire, rarely broken or crushed), (3) the diversity age at death estimated for each of the 5 individuals (3 adults, 1 young adult, 1 adolescent of both sexes). The study dealing with the first discovered mandibles and skulls has begun with Leo Gabounia since 1991 and represents several interests: 1) a paleoanthropological interest: the Dmanissi skulls are characterized by their small size; they are short, narrow and low. The skullcaps are less elevated than those of the Homo erectus group and even those of Homo ergaster. They are more elevated than those of Homo habilis and very close to Homo rudolfensis. The elevation and the transversal development of the middle part of the skull in the parietotemporal region are more significant: the Dmanissi specimens are intermediate between Homo habilis and Homo ergaster. In term of cranial capacity, a similar trend is observed. Generally speaking, the skull is slender. The vault is more flat than in Homo erectus, the frontal bone is less developed, divergent and the postorbital constriction is strong. The temporal bone is long, flat and the mastoid part is short. The upper part of the occipital bone is low and narrow. Crests are thin, less developed than in the Homo erectus group. The superior temporal crests are in a high position and a torus angularis is present on the adult-male specimen. The glenoid cavity is large with strong edges. The petrotympanic region is slender with a tympanic circle individualized and it shows a horizontal rotation in a posterior position, which is distinct from Homo erectus. The orthognathic trend of the face distinguishes the Dmanissi specimens from the early Pleistocene hominids (Homo habilis, Homo ergaster) and from the first Eurasian Homo erectus. Nevertheless, the subnasal region of the face is projected. The morphology of the mid-face, showing a developed pillar of the canine, an inframalar incurvation and an anterior position of the root of the zygomaticomaxillary crest, suggests strong masticatory stress. Considering the overall morphology, cranial and metrical features, the Dmanissi fossil skulls are intermediate to the Homo habilis-rudolfensis group and Homo ergaster while they are closer to the former and peculiarly to Homo rudolfensis (ER 1470). However, the Dmanissi fossil skulls are distinct from Homo rudolfensis by numerous features and among them: by their large maximum cranial width (Euryon-Euryon), the posterior rotation of their petrotympanic structure and the strong development of the pillar of their canine. Due to the gracility of their face, the narrowness of their occipital bone, and their cranial base pattern (mastoid region and petrotympanic structure), the Dmanissi fossil skulls are different from the Homo erectus group: 2) the abundance of the human fossils discovered in Dmanissi site provides information about the biodiversity of these hominids with the establishment of the morphological features related to either growth or sexual patterns: 3) compared to modern humans, the Dmanissi fossil skulls seem to follow a different growth pattern. The present study of the fossil skulls discovered is a pioneer step. Indeed, the Dmanissi site has yielded the oldest evidences of the first settlements in Eurasia, which were, until now, attributed to Homo erectus. The Dmanissi fossil skulls are close to the Homo habilis-rudolfensis African group. We attribute these hominids to Homo georgicus.  相似文献   

2.
A new Homo erectus endocast, Zhoukoudian (ZKD) V, is assessed by comparing it with ZKD II, ZKD III, ZKD X, ZKD XI, ZKD XII, Hexian, Trinil II, Sambungmacan (Sm) 3, Sangiran 2, Sangiran 17, KNM-ER 3733, KNM-WT 15 000, Kabwe, Liujiang and 31 modern Chinese. The endocast of ZKD V has an estimated endocranial volume of 1140 ml. As the geological age of ZKD V is younger than the other ZKD H. erectus, evolutionary changes in brain morphology are evaluated. The brain size of the ZKD specimens increases slightly over time. Compared with the other ZKD endocasts, ZKD V shows important differences, including broader frontal and occipital lobes, some indication of fuller parietal lobes, and relatively large brain size that reflect significant trends documented in later hominin brain evolution. Bivariate and principal component analyses indicate that geographical variation does not characterize the ZKD, African and other Asian specimens. The ZKD endocasts share some common morphological and morphometric features with other H. erectus endocasts that distinguish them from Homo sapiens.  相似文献   

3.
The study of the site of Kocaba?, which yielded an archaic Homo erectus skullcap, was undertaken in 2011 and 2012, at the request of Professor Mehmet Cihat Alçiçek. This interdisciplinary French–Turkish research programme comprised the geochronological, magnetostratigraphic, biochronological and paleoenvironmental study of the site and the paleoanthropological study of the skullcap itself. The association of large mammals enabled us to attribute the travertine formations bearing the skullcap to the second part of the Upper Pleistocene, and more specifically to between 1.5 and 1.2 million years, because of the disappearance or appearance of certain species. This biochronological age is confirmed by the paleomagnetism study, which places the travertines bearing the skullcap in a period of reversed polarity, underlying a normal polarity formation, which could be attributed to the Cobb Mountain paleomagnetic excursion, dated to 1,194,000 years. The dating of these fauna by the 26Al/10Be cosmogenic nuclide method by Anne-Elisabeth Lebatard yielded an age older than 1.22 Ma and more recent than 1.5 Ma. The Hominid skullcap from this formation can be attributed to a Homo erectus, slightly more evolved than those of Homo ergaster KNM-ER 3733 (1.78 Ma) and KNM-ER 15,000 (1.5 Ma), similar to that of Daka (Bouri), which is about a million years old and older than the Bodo fossil (estimated at 600,000 years) and Kabwe (between 300,000 and120,000 years). The archaic Homo erectus skullcap from Kocaba?, referred to as Denizli Man, proves that Homo erectus was already present in Anatolia, at the crossroads of Africa, Asia and Europe, a little more than 1.2 million years ago.  相似文献   

4.
The Anatolia occupies one of the main routes for the dispersal of Homo erectus into the Eurasia. The Acheulean bifaces found on each region of Anatolia are the most important evidences of this situation. This vast distribution of the Acheulean bifaces in Anatolia indicates that all of the Anatolia should stay in the Movius Line. This means that the Movius Line should be reexaminate. Recently, the fossil remains of Homo erectus found in Dmanisi (Georgia) and their very old dates around 1.8 million years put forward the importance of Anatolia one more time. Homo erectus who came in Anatolia by following the Levant Corridor might used the Anatolian bridge for passing to the Transcaucasia. If the well-preserved cave site on the line that expands from Hatay to Kars in Anatolia founds and excavates, it will prove additional information some problems about the Homo erectus movements and distribution of Acheulean Industrial Tradition in West Asia. This paper reviews the evidence for the Acheulean in Anatolia and discusses the distribution of Acheulean bifaces in Anatolia, generally found in open air site.  相似文献   

5.
《Comptes Rendus Palevol》2016,15(5):555-568
Because until 2006 the Liang Bua human fossil remains were not available to the entire paleoanthropological community, the taxonomic position of Homo floresiensis was only a matter of opinion in publications. From the beginning, two schools of thought prevailed, and this situation persists today. One purports that the Liang Bua human series belongs to a local modern human (Homo sapiens sapiens) with anatomical particularities or pathologies that may be due to insular isolation/endogamy. The second argues in favour of the existence of a new species that, depending on the authors, is either a descendant of local Homo erectus, or belongs to a much more basal taxon, closer to archaic Homo or to australopithecines. Because there are no postcranial remains confidently attributed to Homo erectus in the fossil record, and because the Homo erectus type specimen is a single and partial calvaria, a cladistic analysis was undertaken using both nonmetric morphological features and metrics of the calvariae of human fossil specimens including LB1 to test if it belongs to this taxon. Our results indicate that LB1 is included in the Homo erectus clade.  相似文献   

6.
Sangiran (Solo Basin, Central Java, Indonesia) is the singular Homo erectus fossil locale for Early Pleistocene Southeast Asia. Sangiran is the source for more than 80 specimens in deposits with 40Ar/39Ar ages of 1.51-0.9 Ma. In April 2001, we recovered a H. erectus left maxilla fragment (preserving P3- M2) from the Sangiran site of Bapang. The find spot lies at the base of the Bapang Formation type section in cemented gravelly sands traditionally called the Grenzbank Zone. Two meters above the find spot, pumice hornblende has produced an 40Ar/39Ar age of 1.51 ± 0.08 Ma. With the addition of Bpg 2001.04, Sangiran now has five H. erectus maxillae. We compare the new maxilla with homologs representing Sangiran H. erectus, Zhoukoudian H. erectus, Western H. erectus (pooled African and Georgian specimens), and Homo habilis. Greatest contrast is with the Zhoukoudian maxillae, which appear to exhibit a derived pattern of premolar-molar relationships compared to Western and Sangiran H. erectus. The dental patterns suggest distinct demic origins for the earlier H. erectus populations represented at Sangiran and the later population represented at Zhoukoudian. These two east Asian populations, separated by 5000 km and nearly 800 k.yr., may have had separate origins from different African/west Eurasian populations.  相似文献   

7.
Brain development in Homo erectus is a subject of great interest, and the infant calvaria from Mojokerto, Indonesia, has featured prominently in these debates. Some researchers have suggested that the pattern of brain development in H. erectus resembled that of non-human apes, while others argue for a more human-like growth pattern. In this study, we retested hypotheses regarding brain ontogeny in H. erectus using new methods (resampling), and data from additional H. erectus crania. Our results reveal that humans achieve 62% (±10%) and chimpanzees 80% (±9%) of their adult endocranial volume by 0.5–1.5 years of age. Using brain mass data, humans achieve on average 65% and chimpanzees 81% of adult size by 0.5–1.5 years. When compared with adult H. erectus crania (n = 9) from Indonesian sites greater than 1.2 million years old, Mojokerto had reached ∼70% of its adult cranial capacity. Mojokerto thus falls almost directly between the average growth in humans and chimpanzees, and well within the range of both. We therefore suggest that brain development in H. erectus cannot be dichotomized as either ape-like or human-like; it was H. erectus-like. These data indicate that H. erectus may have had a unique developmental pattern that should be considered as an important step along the continuum of brain ontogeny between apes and humans.  相似文献   

8.
Cephalopods and conodonts from the upper part of the Aspe-Brousset Limestones and lower part of the Iraty Limestones in Central and Western Pyrenees are described. Two levels differing in age are distinguished on their behalf. The oldest one belonging to the Late Visean or Early Serpukhovian yields specimens described as Goniatites baylei Leymerie, 1957, by Mirouse (1957, 1962). They are placed here in the species Dombarites falcatoides Ruzhentsev and Bogoslovkaya, 1971 for which the new subspecies D. falcatoides mirousei is established. The upper level corresponds to the Albergian (upper Serpukhovian) and is characterized by Proshumardites delepinei Schindewolf, 1939. Numerous conodonts belonging to the Lochriea and the Gnathodus groups occur together with this fauna. The joint study of goniatites and conodonts allows us to show the relationship existing between the distributions of both these two groups of organisms as well as to provide precisions on the stratigraphic and the palaeogeographical data in these areas.  相似文献   

9.
The archaic Homo erectus Kocaba? skullcap was discovered at Kocaba?, Denizli, Turkey in travertine formations over- and underlain by conglomerate formations. These units dated by the 26Al/10Be cosmogenic nuclide method constrained the skullcap age between 1.0 and 1.6 Ma.  相似文献   

10.
Recent applications of 3D virtual imaging techniques in human palaeontology have increased the possibilities and the accuracy of anthropological analysis. Two examples are given for the reconsideration of fossils discovered more than 20 years ago, thanks to this new technology. The Lower and Middle Pleistocene skulls from Yunxian and Nankin in China, which were damaged in the process of fossilization, have been virtually reconstructed. A detailed reinvestigation has been conducted by considering those reconstructed skulls and their unpublished characters (i.e., inner anatomical features inaccessible until now). The results of this analysis provide new information about the early hominids of China and contribute to the discussion of variability in Homo erectus.  相似文献   

11.
Biostratigraphical high-resolution analyses and quantitative data confirm that deposition is continuous across the K-Pg transition in several sections in Tunisia (El Kef, stratotype section) and Spain (Agost and Caravaca sections) located in the Tethyan realm and the Bidart sections in the Atlantic realm, without any relevant hiatus. The Upper Maastrichtian assemblages of planktic foraminifera from these sections are largely dominated by small biserial heterohelicids. They are associated to common species having planispiral test (i.e. globigerinelloids), trochospiral test (i.e. hedbergellids, rugoglobigerinids globotruncanids), to rare triserial heterohelicids (i.e. guembelitriids) and trochospiral species showing tubulospines (i.e. schackoinids). Stratigraphical ranges of these diverse taxa through the late Maastrichtian in the Tethyan and Atlantic realms show very few changes in the planktonic foraminiferal assemblages and most of the species are present in the Abathomphalus mayaroensis biozone. By our high-resolution sampling and the intensive research for the A. mayaroensis index species in the uppermost Maastrichtian samples, we confirm that this species is omnipresent up to the top of the Maastrichtian. Therefore, A. mayaroensis is present in almost all samples which are late Maastrichtian in age, but this species became very scarce in the uppermost Maastrichtian samples. This scarceness could be due to a climate cooling. A sharp decrease in relative abundance of the deep dwellers species, like as Abathomphalus intermedius and A. mayaroensis as well as in other keeled globotruncanids is observed at the studied sections from the Tethyan realm (indicative of low latitude) across the latest Maastrichtian. At the K/Pg boundary, all the globotruncanids disappeared. They are considered specialists living in tropical-subtropical deep seawater habitat. At this boundary, large and ornate heterohelicids also disappeared. Therefore, all the studied sections show that about 90 % of the Maastrichtian species became extinct according to a catastrophic mass extinction pattern. Only about 10 % crossed the K/Pg boundary and survived during the earliest Danian. The minor difference in the number of disappeared taxa is related to their latitude location or environment paleodepth. The changes in the species relative abundance, observed in the successive planktic foraminiferal assemblages, make it possible to recognize the Acme-stage 0 typical of the upper Maastrichtian interval. It is characterized by the highest species richness of Globotruncanids and heterohelicids specialists of tropical to subtropical marine conditions, the Acme-stage 1 typical of the Guembelitria cretacea Zone, and in particular of the Hedbergella holmdelensis Subzone dominated by “opportunists” species belonging to Guembelitria, the Acme-stage 2 which corresponds to the Pv. eugubina Zone dominated mainly by specimens belonging to Palaeoglobigerina and Parvularugoglobigerina and the Acme-stage 3 which characterizes mainly the Ps. pseudobulloides Zone dominated by biserial species belonging to Chiloguembelina and Woodringina.  相似文献   

12.
This paper presents the results of a biostratigraphic analysis of pyritized diatom assemblages in the Saint-Josse core (CC82) located in the northern part of the Paris basin (coordinates: X =555?000, Y =307?324 and Z =56.9 m). During the Paleocene-Eocene this locality was situated in a small bight of the North Sea Basin. The results are obtained from sediments of the Thanet and Mont-Bernon group equivalents belonging to the Paleocene-Eocene interval. Thirteen samples were studied and eleven contain pyritized diatoms. By epigenesis, the siliceous frustule of the diatom is changed into a pyritized skeleton with all the ornamentation very well preserved such as the velum, the areolae, the labiate processes, etc. Dispersive X-Ray analyses show this complete replacement of silica by pyrite. Another form of pyritization is crystallization of pyrite (in cubes, pyritohedrons, octahedrons, framboids) in internal cavities of the diatoms to produce internal moulds, also called steinkerns, which preserve the external morphology of the diatoms and some details such as the girdle. Despite pyritization, diatoms can often be recognized at the species level; brackish and marine species were observed but no fresh water specimens were encountered. Pyrite is easily altered into iron oxides. In outcrops, pyritized diatoms can be obscured or destroyed by oxidation. We have chosen borehole samples for this study to avoid the affects of weathering. Deposits from the Sorrus Unit (of the Thanet Group) have low abundances of pyritized diatoms (3 to 25 specimens per sample). This unit contains allochtonous diatom assemblages comprising Actinoptychussenarius, Coscinodiscus morsianus var. morsianus, and Coscinodiscus morsianus var. moelleri. Sample 34.31-34.45 from this unit is particularly interesting. It contains three specimens of Paralia siberica var. laevis, which is typical of an estuarine or littoral paleoenvironment, and corresponds to the more continental deposit of the Sorrus Unit. Seven samples, taken in the Argile de Saint-Aubin Unit (from the Mont-Bernon Group), contain more than 200 pyritized diatoms and between 9 to 16 different species per sample. A brackish assemblage (Actinoptychus senarius, Coscinodiscus commutatus and Stellarima microtrias) and a marine assemblage (C. morsianus var. morsianus, Coscinodiscus var. moelleri, Fenestrella antiqua, Odontellaheibergii, Rhizosolenia sp. 1 and Trinacria regina) are observed. The brackish assemblage expands in the upper part of the Saint-Aubin Unit indicating more widespread brackish paleoenvironmental conditions. Pyritized diatoms are important fossil markers in the Paris basin mainly when siliceous fossils (silicoflagellates or radiolarians) and others microfossils (foraminifers and dinoflagellates) are very poor or absent. Two diatom assemblages have been identified in the Saint-Josse borehole. The first assemblage D1, comprising C. morsianus var. moelleri (high occurrence), C. morsianus (a few) and T. regina (rare), is recorded in the Sorrus, La Calotterie, Bois Gorguette, Le Goulet and lower Saint-Aubin Units. The second assemblage D2, characterized by great abundance of F. antiqua and decreasing numbers of C. morsianus species, is found in the upper part of the Saint-Aubin Unit. These diatom assemblages can be correlated with other biozonations established in the North Sea basin and based on nannoplankton and diatoms (King, 1983), diatoms (Mitlehner, 1996) and calcareous nannoplankton (Martini, 1971). F. antiqua and C. morsianus var. moelleri are the more important diatom species encountered. F. antiqua (previously named Coscinodiscus sp. 1, King, 1983) is the fossil marker used by King to define his NSP4 biozone. The base of NSP4 corresponds to the lowest occurrence of F. antiqua and the top is marked by the highest occurrence of this species. The Sorrus, La Calotterie, Bois Gorguette, Le Goulet and Saint-Aubin (“Sparnacian” stage) Units, the last one comprising F. antiqua (increasing to acme), correspond to the NSP4 zone of King (1983). The Mont-Hulin and Château de la Bruyère Units correspond probably to the NSP5 zone of King (1983). F. antiqua and C. morsianus var. moelleri were also used by Mitlehner (1996) to differentiate the NSP4a zone (low abundance of F. antiqua and abundance of C. morsianus var. moelleri) from the NSP4b zone (great abundance and acme of F. antiqua). The abundance of C. morsianus var. moelleri is recorded in the lower part of Saint-Aubin Unit and the abundance of F. antiqua (high peak at 46% in the sample 17.87) is found in the upper part of Saint-Aubin Unit. Therefore, Sorrus, La Calotterie, Bois Gorguette, Le Goulet and the lower part of Saint-Aubin Units are correlated with the NSP4a zone and the upper part of Saint-Aubin Unit with the NSP4b zone. By correlating the calcareous nannoplankton biozonation (NP) of Martini (1971) with the biozonation of King (1983), adapted by Mitlehner (1996), the boundary between the NP9 and NP10 zones could be located in the 18.75-17.87 interval and the NP10-NP11 boundary at the top of Saint-Aubin Unit. Lithostratigraphic correlations between the units of the Saint-Josse borehole (Paris basin) and the formations of the North Sea basin can be established. The great abundance of C. morsianus var. moelleri and the great abundance (including acme) of F. antiqua are respectively recorded in the Sele and Balder Formations. Therefore, the interval Sorrus/lower Saint-Aubin Units is correlated with the Sele Formation and upper part of Saint-Aubin Unit with the Balder Formation.  相似文献   

13.
《Comptes Rendus Palevol》2005,4(3):265-274
A proposal of reconstruction of the second Homo erectus skull from Yunxian (China). In 1989 and 1990, two Homo erectus crania were recovered from Yunxian (Hubei province) in archaeological levels dated to more than 780 000 years. Considered along with Lantian, these skulls represent the oldest human remains discovered in China to date, constituting important palaeontological finds. Nevertheless, the crania were badly deformed during the course of fossilization, necessitating extensive cranial reconstruction. Of the two crania, only Yunxian II was in sufficient condition to carry out this reconstruction. Using sophisticated techniques only recently applied in human palaeontology, including computed tomography and rapid prototyping, and incorporating taphonomic and morphometrically-based hypotheses, we were able to correct virtually the deformation and to produce a 3D prototype of Yunxian II. To cite this article: A. Vialet et al., C. R. Palevol 4 (2005).  相似文献   

14.
The globular braincase of modern humans is distinct from all fossil human species, including our closest extinct relatives, the Neandertals. Such adult shape differences must ultimately be rooted in different developmental patterns, but it is unclear at which point during ontogeny these group characteristics emerge.Here we compared internal shape changes of the braincase from birth to adulthood in Neandertals (N = 10), modern humans (N = 62), and chimpanzees (N = 62). Incomplete fossil specimens, including the two Neandertal newborns from Le Moustier 2 and Mezmaiskaya, were reconstructed using reference-based estimation methods. We used 3D geometric morphometrics to statistically compare shapes of virtual endocasts extracted from computed-tomographic scans. Throughout the analysis, we kept track of possible uncertainties due to the missing data values and small fossil sample sizes.We find that some aspects of endocranial development are shared by the three species. However, in the first year of life, modern humans depart from this presumably ancestral pattern of development. Newborn Neandertals and newborn modern humans have elongated braincases, and similar endocranial volumes. During a ‘globularization-phase’ modern human endocasts change to the globular shape that is characteristic for Homo sapiens. This phase of early development is unique to modern humans, and absent from chimpanzees and Neandertals.Our results support the notion that Neandertals and modern humans reach comparable adult brain sizes via different developmental pathways. The differences between these two human groups are most prominent directly after birth, a critical phase for cognitive development.  相似文献   

15.
16.
The rich echinoid fauna from the Lower Cretaceous of the Agadir, Haha and Essaouira basins has been revised taxonomically, based on new and abundant collections. Forty-seven species have been identified, of which 20 are reported for the first time from this region and a further three represent new species left in open nomenclature. Their stratigraphic ranges have been determined accurately by reference to the regional ammonite zonation. However, it is also possible to use a local biostratigraphical scheme based on the echinoid succession, where ammonites are rare. The Toxasteridae, which are very abundant and underwent rapid evolution, are the most useful biostratigraphically. The genus Toxaster appears in the Lower Berriasian and continues until the Gargasian passing through the following succession: T. africanus, T. granosus, T. kiliani, T. lorioli, T. obtusus, T. exilis, T. retusus, T. maurus, T. peroni, T. collegnoi. The presence of Eoholaster, Macraster, Douvillaster, Palhemiaster, Heteraster and Pygopyrina is signaled for the first time in the Atlantic High Atlas region.  相似文献   

17.
This paper provides an overview of current knowledge of Plio Pleistocene Carnivora from Africa and Europe. In Plio Pleistocene times, many genera extend their ranges in Africa and Eurasia but their evolution are quite distinct in the two continents. In Africa, the modern carnivoran guild of sub saharian Africa originated in the early Pleistocene when took place extinction of archaic species. The north African fossil record is far from complete until the middle Pleistocene. In the middle and late Pleistocene, the modern carnivoran guild is associated with other elements: the simian jackal Canis simensis and two species of ursids Ursus arctos and Ursus deningeri which evolved towards Ursus spelaeus. Western European carnivore faunas show due to migration a constant turn-over of the species. Among felids, Panthera schaubi described by Viret (1954) and attributed to the genus Puma by Hemmer et al. (2004), is morphologically close to the snow leopard Panthera (Uncia) uncia. Canis etruscus is the sister group pf the clade including wolf and coyote and Canis arnensis is close to the African jackals. Ursus deningeri appears in the early Pleistocene together with two arctoid forms Ursus rodei and Ursus dolinensis that may be synonymous to Ursus arctos. The genus Hyaena is present in Europe in the middle and late Pleistocene.  相似文献   

18.
19.
The amber of Le Mas d’Azil (Ariège, France), fashioned by the Magdalenian people of Le Mas d’Azil cave, was collected in clay levels rich in Cupressinoxylon Göppert, of the Campanian Labarre Sandstone Formation, which is a large deltaic set, infilling the sub-Pyreneean trough. The amber pieces are small and resemble modern resin exudates on coniferous trunks. We describe following micro-inclusions. Actinomycetes: Cardonia stellata, nov. gen., nov. sp., located close to the surface of amber pieces, is abundant and displays chains of conidia and isolated aleuriospore. Nocardiopsis ? sp. D is rare. Actinomycete “de type Salignac” is abundant. Its filaments often display a tendril shape, which seems to prelude to a mycelium fragmentation. Other bacteria: Leptotrichites resinatus Schmidt ( Schmidt and Schäfer, 2005), poorly represented, is more variable than the already known material; cf. Sphaerotilus sp., very abundant, also displays differences with the Cenomanian “Sphaerotilus sp.”. Eukaryotes: one fungal filament, and a group of spores, pollens or cysts. Inorganic inclusions: gas bubbles, pseudo-protists of B and C? types, and tiny, transparent, cubic crystals. It seems that most of the quoted prokaryotes were resinicolous organisms, able to settle on the surface of the exudate, and grow in the resin, after inoculation either by a contact with the substrate, or by an anemophilic dispersion of spores. This “taphonomic way” seems here to be more general than trapping.  相似文献   

20.
Among the fossiliferous sites of the Serra da Capivara national park region (South Eastern Piauí), two have yielded interesting remains of the two large Upper Pleistocene Carnivora, Protocyon troglodytes (Lund, 1838) and Smilodon populator Lund, 1842, the Toca da Cima dos Pilão and the Toca das Moendas, both in the municipality of Coronel José Dias. In these two caverns, numerous remains of preys were found, namely, for the Toca da Cima dos Pilão, the two peccaries Dicotyles tajacu and Tayassu pecari, the medium sized ground sloth Catonyx cuvieri and the giant armadillo Pampatherium; for the Toca das Moendas Palaeolama, Equids and Cervids add to that list. The two sites were used as dens by the two Carnivora species. In the Toca das Moendas, a near complete adult skull and a hemimandible of the large Canid P. troglodytes were found. The skull is the third ever known for the species. Its dimensions are very similar to those of a complete skull from the Toca da Boa Vista (Campo Formoso, Bahia, Brazil) described by Cartelle et Langguth (1999), and to those of an incomplete skull from the banks of the Bermejo River (Formosa Province, Argentina), described by Prevosti et al. (2005). It fits perfectly, like the teeth, with the anatomical characteristics of the species P. troglodytes: wide muzzle, short palate, very reduced and forwardly offset protocone of the P4/, etc. The dimensions of the cheek teeth correspond well with those of numerous teeth from Lagoa Santa (Minas Gerais, Brazil) of the Lund Collection preserved in the Zoological Museum of Copenhagen. The same site of Toca das Moendas yielded two left hemimandibles of the Machairodontine S. populator Lund, 1842, an adult and a very young ones. We study them together with other remarkable remains from the Toca da Cima dos Pilão, namely an adult upper canine and an adult hemimandible. The upper canine is one of the longest ever described for S. populator. The P/4 are somewhat longer than those of the Californian Smilodon fatalis (Leidy, 1868), and the M/1 are about of the same average length but somewhat narrower. The segment P/4-M/1 is relatively short. The dimensions of the upper canine and of the lower cheek teeth fit well with those of some teeth from Lagoa Santa (Minas Gerais, Brazil) and from Argentina preserved in the Zoological Museum of Copenhagen. We describe particularly the decidual lower dentition, badly known in that species. The rather weak milk canine has a piriform outline. The D/3 is constituted by a strong protoconid flanked with two small cuspids, an anterior and a posterior ones. The D/4 (deciduous carnassial) shows a strong paraconid followed by a higher protoconid and a small posterior cuspid. These milk teeth, without any abrasion mark, suggest that our young specimen was less than three month old.  相似文献   

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