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1.
Résumé La répartition horizontale du zooplancton est étudiée; l'accent est mis sur la disposition relative des agrégats des diverses espèses et sur l'évolution de l'agrégation de ces espèces en fonction du temps et de l'intensité lumineuse incidente. Des précisions sont données qaunt aux pourcentages des divers stades d'une espèce dans et en dehors des agrégats.La répartition verticale des espèces et de leurs divers stades est décrite. Les fluctuations en surface au cours de 24 heures du nombre d'individus de toutes les espèces planctoniques et de leurs divers stades sont examinées et font l'objet d'une discussion.Institut Royal des Sciences Naturelles de Belgique Section Hydrobiologie (Dir.: Dr. G. Marlier)  相似文献   

2.
This paper summarizes the latest studies on lithic raw material raising that are currently undertaken within the Sierra de Atapuerca research project. During the past two years, several works have provided new petrographical and technological data, contributing to the knowledge of the kinds of materials exploited by the Atapuerca hominids, as well as the areas where those materials were raised. The sites yielding this information are Gran Dolina (Lower and Middle Pleistocene) and Galeria (Middle Pleistocene), both located in the Trinchera del Ferrocarril archeopaleontological complex.  相似文献   

3.
The archaeological localities of Barranco León and Fuente Nueva 3 in Orce, Grenade, in actuality have the oldest lithic artifacts in Europe; they are the oldest evidence of human occupation in the east of Europe. When compared the results from faunal analysis and magnetostratigraphical study, notably through the presence of Allophaiomys lavocati allow for a date of around 1.3 Ma. The raw material used for developing these lithic industries are, basically limestone or siliceous rocks, these raw materials selected were smoothed down in situ. The techniques used are knapping at raised with a hammerstone, and we can find all the different elements of the “chaine opératoire”. Both localities are characterised by the predominance of flakes and debris, cores, and some knapped cobbles sowing mediocre aspect. The technical and typological features of both lithic assemblages have an opportunist character but they are relatively sophisticated too.  相似文献   

4.
In Lymnea stagnalis (F 1 generation) carbaryl weakly disturbs the growth of the shell with 2 ppm, strongly with 4 ppm (lethal concentration for the young snails).The shell growth inhibition by lindane is correlated with the concentration (1 & 2 ppm). The degree of intoxication of parents is very important. The two insecticides play a complex part in the mineralization of the shell. The effects of lindane on growth and mineralization of the shell have a reversible character.  相似文献   

5.
Variability is one of the most debated topics in lithic technology studies. For the Middle Pleistocene period, this debate has specifically focused on the significance of large cutting tools such as handaxes and cleavers. This paper presents the stone tool assemblage from Covacha de los Zarpazos site, included in the Galería complex at Sierra de Atapuerca (Burgos, Spain). We analyse the management of lithic raw materials, the reduction sequences identified, and the morphological variation in the shape of large cutting tools. The results show that raw materials play an important role in the final variability of tool shape, although they do not represent any real constraint. However, what determines the main variability of a whole lithic assemblage is the occupation strategy and the specific activities carried out in a given site.  相似文献   

6.
Résumé Des papillons de carpocapse Cydia pomonella L., mâles et femelles séparés, sont soumis au contact des résidus secs du CGA 184'699, un inhibiteur de croissance d'insectes (ICI) et du fenoxycarb, un régulateur de croissance d'insectes (RCI). Ils sont ensuite regroupés dans boîtes non traitées pour l'accouplement et la ponte. La fécondité du carpocapse n'est pratiquement pas affectée par ce conditionnement mais sa fertilité diminue avec l'augmentation de la concentration des produits et avec la durée d'exposition. Avec le CGA 184'699, l'efficacité ovicide induite atteint environ 50% suite à un contact de trois jours avec les résidus d'un traitement à 100 mg/l, alors qu'avec le fenoxycarb elle s'élève à 87% dans les mêmes conditions. Avec le CGA 184'699, seul le contact des femelles avec les résidus provoque cette réduction de fertilité, alors que le fenoxycarb agit sur les deux sexes.
Summary Codling moth, Cydia pomonella L., males and females were exposed separately to contact with dry residues of CGA 184'699 an insect growth inhibitor (IGI) and fenoxycarb, an insect growth regulator (IGR), The sexes were then grouped together in non treated boxes for mating and egglaying. Fecundity of codling moth was little affected by this treatment but its fertility decreased with increases in the concentration of products and the duration of contact. Induced ovicidal efficacy was about 50% after three days contact with the residues of a 100 mg (a.i.)/l application of CGA 184'699, whereas the same conditions led to about 87% efficacy with fenoxycarb. With CGA 184'699, only contact by females affected egg eclosion whereas fenoxycarb acted on both sexes.
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7.
Pour rechercher son partenaire sexuel Zabrotes subfasciatus doit utiliser les signaux olfactifs émis soit par les mâles ou par les femelles. Le pouvoir attractif de l'odeur des mâles et des femelles sont donc étudiés et comparés par olfactométrie. Le comportement de mâles et de femelles vierges et inséminées, mis en contact des graines de la plante hôte ou non, est observé en fonction de l'âge des imagos. En aucun cas, les odeurs des mâles n'exercent une attraction sur les femelles. Les femelles vierges en absence de graines de haricot (Phaseolus vulgaris) n'exercent pas d'attraction sur les mâles vierges. Par contre les odeurs des femelles vierges mises en contact avec les graines de haricot sont très attractives pour les mâles vierges et varie en fonction de l'âge: il est plus affirmé chez les femelles plus âgées. L'émission de la phéromone sexuelle est interrompue après l'insémination des femelles mais reprend au bout d'un certain temps après celle-ci.  相似文献   

8.
The archaic lithic industries of Barranco León and Fuente Nueva sites in Orce in Andalusia and the stone tools of the Vallonnet french site was studied by petroarcheological analyses and reveal the sources exploited by the hominids. The localisation of these sources give data to define the territory exploited. These three examples provide the opportunity to assess the raw material selectivity, the behaviour and the territory occupation system of the first inhabitants of Europe. These lithic industries are composed by local raw material collected very close to the site or even on the site. These sources were probably an important argument on choosing the occupation site.  相似文献   

9.
Located in the Aure Valley (French central Pyrénées), the Noisetier cave opens at 825 m asl. This Middle Palaeolithic site has produced a Mousterian industry associated with a rich faunal assemblage. Bone remains are dominated by Chamois then Ibex and Red deer. Taphonomic analysis strongly suggests a human origin for the Ibex and the Red deer but questions arise for the Chamois. The chamois assemblage differed from the bones of both species by its low cut marks ratio. Semi-digested bones are particularly abundant. Differences are even more perceptible for skeletal portions. For Red deer and Ibex, long bone remains are mostly shaft portions whereas for Chamois, ends are the most abundant. Comparisons of the Noisetier cave bone assemblage with different present-day reference data leads to the conclusion that Chamois bones have mostly been accumulated by bearded vultures.  相似文献   

10.
The Late Jurassic - Early Cretaceous series encountered in South-East Tunisia, formely considered globally as Purbecko-Wealdian in age, has the most complete palaeobotanical record of all North-Gondwana. Thanks to the stratigraphical results of the last years and to new field researches, it was possible, for the first time, to evidence an Oxfordian flora at the base of this series (Bir Miteur Formation). This flora, constituted of impressions and axes of Pteridophytes and Gymnosperms, is encountered within different types of plant-bearing levels. The study of deposit facies and sequential analysis of this Oxfordian formation allowed the identification of corresponding sedimentary environments and to infer their palaeoecological meaning. The discovery of exceptional specimens provided new informations about the general morpho-anatomy of Alstaettia, a very peculiar tree fern of a now extinct type. This Oxfordian flora is an interesting key-point in the evolution of North-Gondwanian flora at the Jurassic/Cretaceous transition.  相似文献   

11.
A 122 cm-long core was taken in the El-Guettiate Sebkha of Skhira (southeastern part of Tunisia) in order to investigate the recent palaeoenvironmental evolution of this region. The quantitative and qualitative analysis of ostracod and benthic foraminifera assemblages coupled with a correspondence analysis allows the reconstruction of palaeoenvironmental changes during the Holocene in this area. Four typical associations of ostracods (open marine, coastal marine, lagoonal and estuarine brackish) and two associations of benthic foraminifera (coastal and lagoonal) were distinguished. The onset of restricted lagoonal environments linked to the building-up of sand spit led to the onset of restricted lagoon and brackish environment at cal. 5408 years BP. The Shannon and equitability index of diversity were used to decipher the structural variations of the populations of ostracods and benthic foraminifera along the sampled core. We note a reduction in the Shannon index from the bottom to the top, which indicates a progressive isolation of the biotope. The open lagoonal episode is characterized by high values of diversity. During restricted lagoonal episodes the Shannon and equitability index are reduced. The correspondence analysis reveals an environmental gradient related to the marine influence. It shows an antagonism between the widely opened estuarian lagoonal species and those of restricted lagoon. The less opened estuarian lagoonal taxa occupy an intermediate position. Based on these evidences, microfauna carried out in the El-Guettiate Sebkha allows us to recognize four phases beginning with a widely opened estuarian lagoon (ca. cal. 7460 years PB), followed by a restricted lagoon (ca. cal. 5408 years BP) and finally a brackish lagoon evolving towards the present-day sebkha environment. The opened estuarine lagoon is characterized by high values of species richness and diversity indices.  相似文献   

12.
Do the decorated productions cover esthetics, i.e. the whole of the symbolic systems of a culture of hunters-gatherers? How to leave this glance with the aesthetic requirements that we other Westerners, pose on all things… and to exceed the debate of the artistic expressions thought from the aesthetic point of view, like “works of art” objects and “stylistics” objects? It is out of question “to make a fetish” of the productions decorated “works of art” while placing them at the starting point with our reflexion, (Studying them from a functional, technological, typological, art for art, meaningful point of view…) but to associate another of dimensions of the aesthetic experiment, i.e., the context of the decorated productions.  相似文献   

13.
After the previous lacking evidence allowed the interpretation of a non-deposition episod, the newly recorded mammal fauna from Puycelci (Tarn, SW France, close South to the Quercy paleokarstic area) now shows the MP 26 standard level (Late Oligocene, Early Chattian) being represented within the Eastern Aquitaine molassic basin filling. According to the evolutionary stage of known mammal lineages, the most significant Puycelci fossils are the Issiodoromys pauffiensis rodent and the Metriotherium cf. sarelense nov. sp. (described in this paper) artiodactyl ungulate. This new dating exemplifies the improvement of the mammalian biochronologic record as regards both the Quercy paleokarst and the surrounding lacustrine Tertiary basins W, S, and S-E to the Quercy, as well as, directly E and N-E, the smaller tectonic Tertiary basins within the crystalline Massif Central basement. The updated record shows the strong extension in time of the paleokarstic data, down to the Middle and Early Eocene, and up to the Early Miocene. Regarding the classically reported Late Eocene to Late Oligocene span, as well in the paleokarst and the peripheral basins, the available biochronological data now attains a valuable density level, the variation of which is significant. On one side there are periods (Late Eocene, Early Oligocene, Early Late Oligocene) with high biochronologic density, allowing improved time resolution using evolutionary stages within mammalian lineages (e.g. numerical ages). Such periods corresponds to almost continuous sedimentary processes, with only possible short breaks. On the other side, there are periods with unreported data, shared in the paleokarst and peripheral basins (Late Oligocene as best example). Such periods may well correspond to some non-deposition episods as once alleged by geologists. Then the surrounding biochronologic data would bear constraining value regarding these episods.  相似文献   

14.
The paleontological analysis of the fauna from three Late Pleistocene localities in Southern Caucasus (Saka?hia, Ortvala, and Bronze cave) confirmed the presence of Ursus spelaeus, Canis lupus, Equus ferus, Rhinocerotidae, Cervus elaphus, Capreolus capreolus, Alces alces, Bison priscus, Capra caucasica, Ovis ammon and Sus scrofa. The study also permitted the identification of new taxa for these localities. There may be the presence of reindeer (Rangifer tarandus) at Saka?hia, however it has not yet been confirmed. Moreover, remains of aurochs (Bos primigenius) were identified, in particular at Bronze cave where its abundance is exceptional. Indeed, Bos and Bison are generally very rare in Southern Caucasus. The analysis of the proportion of the different species in each locality revealed the two types of occupations of the caves, one dominated by hominids and the other by carnivores. At Saka?hia, where fauna is dominated by the presence of cave bear, the cave was seasonally occupied by Neanderthal groups. On the other hand, Bronze cave corresponds to a habitat of hunters, which occupied the site for longer periods.  相似文献   

15.
Mediterranean Languedoc is a vast region in Southern France where Mousterian occupations, mainly concentrated in the eastern sector, are numerous. The three lithic series of the open-air sites presented in this article are yet unpublished. The techno-economical approach used to analyse these three stone assemblages has brought to light variability in Neandertal behaviour concerning raw material collection and economy in sectors more or less rich in siliceous resources, and also concerning the different production systems used and their goals. Comparisons made with other Mousterian stone assemblages in Languedoc seem to indicate ties with certain sites from the Rhône Valley.  相似文献   

16.
Many exposures assigned to the Miocene formation of “Marnes de Saubrigues” (southwestern Aquitaine Basin) have been studied. Their revised stratigraphical allocation has made it possible to recognize mainly Middle to Late Burdigalian age deposits which have been widely sampled. They have been correlated with planktonic zones N6 pars-N7 and NN3-NN4 and locally dated 17.7 Ma with Sr isotopes. It is noteworthy that this chronological interval is only known in the southern Basin. An inventory of the rather abundant microplankton is provided, including series crossed by drillings in the Gulf of Biscay. These deposits yield a large diversity of benthic foraminifera, nearly 400 taxa, which can be considered as a reference fauna for western Europe Burdigalian. From a geographic point of view, it has been possible to subdivise the exposures into groups according to their bathymetry. Let us point out the first discovery of Borelis in the Burdigalian of France and in the northeastern Atlantic Miocene as well. Very rare specimens of Cycloclypeus are also present in the Aquitaine Basin. Among smaller foraminifera, the occurrence of Rosalina aguayoi, Pavonitina styriaca, the last appearance of Falsocibicides aquitanicus and the persistance of the genus Almaena must be emphasized. Several assemblages supply diatoms, rare radiolaria and sometimes abundant sponge spicules; the presence of these organisms, seldom reported from the Aquitaine Tertiary, might be linked to upwelling-type currents. Bachmayerella (inc. sed.) is uncommon and cited for the first time in the Burdigalian. A few taxonomical remarks and short notes are given for some species of foraminifera, and palaeoecological details as well. Numerous taxa are represented and comparisons with the foraminifera faunas mainly from the Lower-Middle Miocene of Western Mediterranean and Paratethys are sketched.  相似文献   

17.
Résumé Chez Diadromus pulchellus WSM et D. collaris Gr., Hyménoptères Ichneumonidés parasitoïdes spécialistes des nymphes d'A. assectella lépidoptère inféodé aux Allium, des EAG sont enregistrés en réponse à l'odeur du poireau sain ou attaqué par les larves du phytophage, odeurs actives par ailleurs sur leur comportement locomoteur (cinèses). Le thiosulfinate de dipropyle (Ti-P2) très spécifique et abondant dans les Allium, et instable, est le mieux perçu par les deux parasitoïdes mais n'a aucun effet locomoteur chez D. pulchellus contrairement aux disulfures et thiosulfonates, plus stables et moins spécifiques. Les propriétés de l'acétate d'éthyle, actif sur l'antenne des deux parasitoïdes, et sur la locomotion de D. pulchellus expliqueraient en partie les activités biologiques du poireau attaqué sur ces parasitoïdes. Des EAG sont aussi obtenus chez les deux espèces avec l'odeur du chou et de composés soufrés plus ou moins spécifiques des Crucifères. Le thiocyanate de méthyle (TCN-M), le plus actif sur l'antenne et seul efficace sur le comportement locomoteur (de D. pulchellus), expliquerait en partie l'installation reconnue de D. collaris sur Plutella maculipennis spécialiste des Crucifères et rend celle de D. pulchelles vraisemblable.L'odeur des larves de dernier stade d'A. assectella est seule efficace sur l'antenne et la locomotion des femelles de D. pulchellus. Les mâles de ce dernier réagissent (EAG, locomotion) à des odeurs de cocons de l'hôte et particulièrement à ceux occupés par une femelle de leur espèce.  相似文献   

18.
Vallonnet cave (Alpes-Maritimes, France) provided archaic lithic tools together with a big amount of large mammals of the end of lower pleistocene. At the crossing of diverse ecological niches in time and space, three main levels and within them several smaller units were distinguished. The poorly mineralized bones witnessed a huge diagenetic fragmentation. The presence of the animals in the cave seems to be linked to the reasons of their death. The exhaustive and systematic observation of the bones, like the bears probably used to die inside the cave. Some other carnivores especially hyenas, used the cave as a nursery. Man also occupied the cave and had an activity mainly on large cervid bones and on some other species as well. The very progressive deposit gave a way for carnivores and porcupine to gnaw the bones on the ground before their burial. The succession of actions (man, carnivores and porcupine) on the same bones is characteristic on Vallonnet large mammals bones.  相似文献   

19.
As one of the most important Lower Pleistocene sites of the Nihewan basin in North China, Donggutuo (DGT) site is well known for its fine retouched small tools and characters of flake industry. However, new excavations still reveal some new discoveries and educe some new issues to us. For example, the “DGT core” introduced in this article is a new discovered typotechnology and indicates new economic strategy of the local people, which was never known before in this area at the time of 1.1 Ma B.P. The paper provides general background and statistic analysis of DGT industry including special method applied to the “DGT core” and discusses possible influence of environmental change for the emerging of the “DGT core”. The “DGT core” shows a germinated microlithic tradition and reflects a cultural diversity of early humans in the Lower Paleolithic in North China.  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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