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191.
In the course of a study on the diet of two Portuguese carnivores, the red fox (Vulpes vulpes Linnaeus) and the common genet (Genetta genetta Linnaeus), 276 ticks were found inside the 940 scats analyzed. Prevalence in samples was 7.6% for both predators. Association of ticks with prey identified on scats, resulted in new data for Portugal on host-tick interactions [e.g. Ixodes acuminatus (Neumann, 1901) and wood mouse] and tick distribution pattern. These unusual findings, besides shedding some light on the host-tick Portuguese assemblage, revealed scats as a new source of biological information.  相似文献   
192.
193.
About eighty Paleolithic sites are presently known in Bose basin (West of Guangxi autonomous region, South China). The sites are extensively spread on the fourth terrace of the Youjiang River. They are dated to 0.8 my, thanks to the presence in the archaeological layers of tektites, residues from a major meteoritic event, in association with the archeological materials. Only about twenty sites have been actually excavated and handaxes have been very recently discovered in stratigraphic context. The archeological material exclusively includes lithic industry which is mainly constituted by unifacial pebble tools made on coarse grain rocks: choppers, but also handaxes and picks. The technology used is very simple and there are no spheroids which usually characterize a lot of Chinese sites of this period. Bose handaxes, thought their number is quite low, remind of the western Acheulian.  相似文献   
194.
The Nobel Prize for chemistry of 1955 was awarded to Vincent du Vigneaud. After a brief outline of his career and accomplishments, some archive material related to this decision of the Royal Swedish Academy of Sciences is presented. Other archive studies have shown that du Vigneaud was also considered for the corresponding prize in physiology or medicine.  相似文献   
195.
The present work provides a detailed analysis of the reproductive strategy of the undulate ray Raja undulata in Portuguese mainland waters. The species was found mostly between 30 and 40 m deep on sandy bottoms. Egg‐laying sites were observed in the north, centre and south‐west regions, mainly at depths below 30 m. The peak of the reproductive season occurred from December to May. Asynchrony between reproductively active females and males appeared to occur, although most adult males were capable of reproducing throughout the year. The estimated length at 50% maturity was 86·2 cm (8·7 years) and 76·8 cm (7·6 years) total length for females and males, respectively. The maximum potential fecundity was estimated to be 69·8 follicles per female per reproductive season, which are released in 4·7 batches of 15 follicles. The life‐history and demographic parameters of R. undulata are similar to those of other skate species, while the potential rate of population increase (0·49) is above the published values for other elasmobranch species. With these new findings, this study makes an important contribution to the understanding of the life history of R. undulata, and provides a first evaluation of the productivity and susceptibility of the species to exploitation.  相似文献   
196.
Two new Late Jurassic (uppermost Late Kimmeridgian) dinosaur eggshell sites are described, Casal da Rola and Porto das Barcas, both near Lourinhã, central-west Portugal. Casal da Rola yields eggshells with an obliquiprismatic morphotype comparable to those from a nest with the associated fossil embryos from Paimogo, tentatively assigned to the theropod Lourinhanosaurus antunesi. The Porto das Barcas eggshells have a dendrospherulitic morphotype with a prolatocanaliculate pore system. This morphotype was also recognised in eggshells from a clutch with associated Torvosaurus embryos at the Porto das Barcas locality. A preliminary cladistic analysis of eggshell morphology suggests theropod affinities for the Casal da Rola eggs, but is unable to resolve the phylogenetic position of the Porto das Barcas eggs. The eggshells at both sites are preserved in distal flood plain mudstones and siltstones. Carbonate concretions within the deposits indicate paleosol development.  相似文献   
197.
Platynematum salinarum nov. spec. was discovered in a hypersaline (∼120‰) solar saltern in Portugal. Its morphology, ontogenesis, and 18S rRNA were studied with routine methods. Platynematum salinarum has a size of about 35 μm × 18 μm and differs from other platynematids (= Platynematum and Pseudoplatynematum) in having an only slightly flattened body without any spines or notches. Both, the oral and somatic infraciliature resemble other platynematids and the tetrahymenid pattern in general. The ontogenesis is scuticobuccokinetal, being unique in generating protomembranelle 1 from kinetids produced by the paroral membrane of the proter and of the scutica. This composite divides transversely: the right half becomes the paroral membrane of the opisthe, the left half transforms to opisthe's adoral membranelle 1. The scutica and the molecular sequence classify P. salinarum into the order Scuticociliatida, family Cinetochilidae. The 18S rRNA sequence shows 92.7% similarity to the closest relative deposited in public databases (the scuticociliate Sathrophilus holtae), and our study provides the first sequence for the genus Platynematum. Experiments at different salinities show growth between 120‰ and 300‰, survival at 100‰, and cell death around 60‰ salinity, characterizing P. salinarum as a true halophile.  相似文献   
198.
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   
199.
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   
200.
Parco cave, discovered in 1974, has yielded more than 50 objects fashioned of hard animal parts from levels dating to later phases of the Magdalenian. In the work described here, we have undertaken a technotypological analysis of this previously unstudied bone and antler assemblage. The osseous series from Parco are homogeneous and very similar to those from nearby sites of roughly the same time period; that is to say of the late Upper Magdalenian of the peninsular Mediterranean. The latter are composed primarily of hunting weapons dominated by antler projectile points, as well as eyed bone needles and a few shell ornaments. Technological analysis shows production in which there is a tight relationship between morphological type and raw material employed. The production schema saw the removal of blanks by means of groove and splinter technique, followed by shaping of pieces by scraping and finishing of them - in some cases by abrasion.  相似文献   
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