首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
2.
The presence of constitutive alkali-labile sites (ALS) has been investigated using a protocol of DNA breakage detection-fluorescence in situ hybridization and comet assay in spermatozoa of donkey (Equus asinus) and stallion (Equus caballus). These results were compared with those obtained using a similar experimental approach using somatic cells. The relative abundance of ALS was of the order of four times more in spermatozoa than in somatic cells. Alkali-labile sites showed a tendency to cluster localized at the equatorial-distal regions of the sperm. The amount of hybridized signal in the ALS in the sperm of donkey (Equus asinus) was 1.3 times greater than in stallion (Equus caballus), and the length of the comet tail obtained in donkey sperm was 1.6 times longer than that observed in stallion (P < 0.05); however, these differences were not appreciated in somatic cells. In conclusion, ALS localization in sperm is not a randomized event and a different pattern of ALS distribution occurs for each species. These results suggest that ALS represents a species-specific issue related to chromatin organization in sperm and somatic cells in mammalian species, and they might diverge even with very short phylogenetic distances.  相似文献   

3.
We mapped six genes (EIF4G3, HSP90, RBBP6, IL8, TERT, and TERC) on the chromosomes of Equus caballus, Equus asinus, Equus grevyi, and Equus burchelli by fluorescence in situ hybridization. Our results add six type I markers to the cytogenetic map of these species and provide new information on the comparative genomics of the genus Equus.  相似文献   

4.
The Equus specimens of Andersson Loc. 32 in Qixian, Shanxi previously identified as Equus cf. sanmeniensis are rediscovered in this research. The skull has moderate size, deep nasal notch, clear preorbital fossa, undulated lateral outline, upper cheek tooth with simple fossette and incisor with incomplete cup, should be identified as Equus teilhardi. The mandible has cheek tooth with V-shaped linguaflexid, incisor with incomplete cup, moderate size, strong pli caballinid and deep ectoflexid on molar, should be identified as Equus qingyangensis. This skull is first record of a complete cranial material of E. teilhardi, reveals many important cranial features of E. teilhardi, supports anatomical comparison and phylogenetic discussion with other stenonid horses. The morphological differences between E. teilhardi and E. qingyangensis show their different niches, further explain the reason of their coexistence. Incomplete cup on incisor is an unstable feature. It has been found in several species of stenonid horses, likely a remaining feature derived from the most primitive Equus, Equus simplicidens. The small-sized stenonid horses with short limbs and incisors with incomplete cups likely have relation with E. teilhardi, such as Equus yunnanensis and Equus stehlini. E. qingyangensis has most primitive features in Eurasian stenonid horses.  相似文献   

5.
Cytochrome c of the zebra (Equus guagga Boehmi) differs from horse cytochrome c in having in its polypeptide chain one serine residue instead of none and 9 threonine residues instead of 10. This replacement has been localised at position 47 of the sequence.  相似文献   

6.
Stjepan Kr?mar 《ZooKeys》2012,(234):19-57
The present paper is based on original and literature data. In Croatia the first studies on the occurrence of ixodid species were made about 80 years ago. The number of tick species recorded in Croatia considerably increased during the 1950s, 60s, 70s and 80s of the past century. A total of 21 species of hard tick belonging to 5 genera have been recorded in Croatia. Ixodes is the best represented genus, with seven species recorded. Haemaphysalis is represented by six species, followed by Rhipicephalus with four species. Dermacentor and Hyalomma are represented by two species each. The ticks were collected on 47 different host species. Eleven tick species were collected on Bos taurus and Ovis aries, followed by Capra hircus and Equus caballus with 8 species and Canis lupus familiaris with 6 species. On the remaining 42 host species one, two or three tick species were collected. The most widespread tick is Ixodes ricinus which was found on 25 different host species.  相似文献   

7.
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   

8.
《L'Anthropologie》2021,125(1):102850
The Mousterian open air site of Mirefleurs is located on a versant dominated by a basaltic flow, in the Allier valley (Fig. 1). Since 1970's, the site has been digged several times. This paper presents the results of several diggs located in different parts of the site. The stratigraphic data result from an intervention realized in 2003. The site of Mirefleurs delivered a lithic industry and a plentiful fauna, disrupted in various times by solifluxion (Fig. 3). Fauna is widely dominated by Horse, which shows more affinities with Equus caballus germanicus than with the shape of the upper Palaeolithic Equus caballus gallicus (Prat, 1968; Guadelli, 1987) (Tables 3 to 32). The characteristics of this animal indicate an age near the end of isotopic stage 3, corresponding at a cold and dry environment. The AMS datations realized on horse bones give an age of 37,700 ± 2600 BP and 28,210 ± 820 BP. The absence of marks of carnivores on the bones lets suppose an unimportant participation of these last ones and a human origin in the implementation of this accumulation of bones. It seems that horses have been killed without any selection and with an important waste. This behaviour would explain the low representation of males, the strong representation of the adults and the small quantity of notches observed on bones. Lithic industry indicates a local exploitation of raw materials (Table 44). Discoïde and centripetal recurrent débitage are dominant (Figs. 9–11). Blanks are mostly retouched in different kinds of scrapers (Figs. 12 and 13). A second chaîne opératoire concerns flint tablets, which are retouched in some bifacial scrapers. Technological and typological characteristics of this lithic industry allow an attribution to Quina Mousterian (Niederlander et al., 1956; Combier, 1967; Le Tensorer, 1978).  相似文献   

9.
In the majority of extant placental mammals the bulla tympanica is composed of two skeletal elements, the entotympanic and the ectotympanic. Former studies revealed that the presence of an entotympanic in the bulla tympanica of extant Perissodactyla is restricted to Rhinocerotidae. The existence of the entotympanic in Tapiridae and Equidae remained speculative. Here we present the first evidence of an entotympanic, strictly speaking rostral entotympanic, in the domestic horse, Equus caballus. The enchondrally ossified entotympanic can be easily separated from the desmal ectotympanic by its greater thickness and by its cancellous bone texture in a late fetal stage. Both elements are separated by a suture that is in the process of coalescence. The complete fusion of the two elements and the unification of bone texture are almost accomplished at birth but the entotympanic and ectotympanic assume the same thickness obviously not until early postnatal development. Based on modern phylogenetic hypotheses we can conclude that the common ancestor of Perissodactyla must have possessed a well-developed entotympanic, probably only evident in their fetal life. This must be considered as a plesiomorphic character state of this order, because the entotympanic is a neomorphic apomorphy of placental mammals. However, the prenatal fusion of the entotympanic and the ectotympanic is an apomorphy of Equus caballus and possibly of the Equidae as a whole.  相似文献   

10.
The Villafranchian fossil record of Perissodactyla is of a great interest because the appearance of the genus Equus and disappearance of the genus Tapirus mark important faunal turnovers. Here, we provide new data on Italian Villafranchian Tapiridae, Rhinocerotidae, and Equidae with updates from the last comprehensive review; most relevant are those of the Rhinocerotidae and Equidae. At present only two Villafranchian rhinoceros’ species are documented in Italy: Stephanorhinus jeanvireti and Stephanorhinus etruscus. The two species can be distinguished by several morphological features and by the dimensions of their bones. Stephanorhinus etruscus occurred throughout the Villafranchian; despite the numerous records, its remains are not enough to investigate morphometric trends. The Equidae include seven species including new occurrences of Hipparionine horses and of the genus Equus. The statistical analyses performed on the Equus species show two different evolutionary trends, namely the stenonine lineage “Equus livenzovensis - Equus stenonis” and the small-to-medium-sized lineage “Equus senenzensis - Equus stehlini”, suggesting a different evolution of these species. Moreover, the analyses show close relationships between the Italian Equus stenonis samples and three European Equus stenonis subspecies (E. stenonis vireti, E. stenonis guthi, and E. stenonis pueblensis). We begin to reconsider the validity of E. stenonis subspecies identification in order to provide new perspectives on the taxonomy of this species.  相似文献   

11.
Stable carbon and oxygen isotope analyses of mammalian carnivoran and herbivore species from the late Pleistocene Valdegoba cave site in northern Spain imply competition and partitioning in resource use. In general, the data support the previously recognized ecology for the analyzed species. δ13C values show that the ecosystem around the cave was dominated by C3 plants. The observed δ18O values are similar to what is found in modern environments. The analyzed bovids, Bos primigenius, Capra pyrenaica, and Rupicapra rupicapra, showed the most positive δ13C values. Bos primigenius had the most positive mean carbon isotope value and is suggested to feed on grasses in open environments. Values for Capra pyrenaica primarily indicate grass feeding, while Rupicapra rupicapra had the widest diet for the analyzed species, likely including grass and browse. Cervus elaphus, Equus ferus, Equus hydruntinus, and Stephanorhinus hemitoechus displayed more negative δ13C values indicating the use of similar resources. The smallest species analyzed, Castor fiber, displayed the most negative δ13C and δ18O values, implying a preference for eating C3 plants and being semi-aquatic. The canids, Canis lupus and Vulpes vulpes, displayed the most positive δ13C and δ18O values, and overlap many of the sampled ungulate species. Positive δ18O values in canids implies that this group obtains much of its water from its prey, uses a different water source, or has physiological differences from the other carnivorans that influence oxygen isotope values. Lynx pardinus had values similar to the canids. Crocuta crocuta had δ13C values more negative than expected for a generalist predator. These values are likely due to concentration of diet on taxa from more forested environments. The most negative δ13C values are observed in the bears, Ursus arctos and Ursus spelaeus. These values are the likely result of hibernation and the inclusion of significant vegetation in bear diets.  相似文献   

12.
The wall of Aremoricanium rigaudaeDeunff, 1955, type-species by original designation of the genus AremoricaniumDeunff, 1955, is composed of two layers: the internal one has a circular opening while the second is the only one which develops the processes and a tubular expansion.  相似文献   

13.
The Upper Pleistocene site Belobaka XVII (about 20,000 years) has yielded some Hippopotami remains included in a very hard breccia. Among this material two lower premolars, a juvenile calcaneus, two juvenile metatarsals and a first abaxial phalange have been cleaned and can be studied. They belong to Hippopotamus laloumena Faure and Guérin, 1990, allowed us to know for the first time the P/2 and P/3 of that species and confirm its validity. Belobaka is then the third Malagasyan site where H. laloumena has been found, and the first which yielded Pleistocene hippopotami remains.  相似文献   

14.
The group density of four species of cave fishes (Caecobarbus geertsi, Barbopsis devecchii, Astyanax gen. and Uegitglanis zammaranoi) and of two taxonomically related epigean species (Barbus conchonius and Hyphessobricon scholzei) was measured tridimensionally in an experimental aquarium, using a video recorder and a mirror inclined at 45° placed on top of the aquarium. The experiments were conducted in dim red light. The illumination was continuous in the case of cave fishes. For the epigean forms a 12/12 LD cycle was superimposed using dim achromatic sources. The relative positions of individuals within their own specific group were registered hourly during a week (168 h). Results show that in cave forms, the mean density of groups falls within the theoretical limits of random distribution values in all cases, whereas epigean species display a non-random aggregation tendency.  相似文献   

15.
The Anagni intra-apennine basin is especially rich in palaeontological and archaeological sites, spanning between middle Villafranchian and upper Pleistocene. The Italian Institute of Human Palaeontology has carried out researches in this region in the last 30 years. At Costa San Giacomo, middle Villafranchian yellow sands contain Mastodon arvernensis and Elephas meridionalis. At Colle Marino, a travertine layer and lime-clay contains mode 1 lithic industry, below any volcanic layers whose lower limit is 700 Ky old. Excavations have been restarted at Fontana Ranuccio, a 458 Ky Acheulian site with rich mammalian fauna (Elephas antiquus, Ursus deningeri, Bos primigenius, Dama clactoniana, Equus mosbachensis), a remarkable bone industry and four human teeth. Drillings, for about 40 m, have identified Matuyama-Brunhes limit 23 m under the main volcanic pyroclastite, in a thick limnic clay layer.  相似文献   

16.
An identification system based on the individual stripe patterns, has been developed for zebra (Equus burchelli, Gray). A taxonomic nomenclature facilitates easy field classification into a number of classes, which form the basis for a photo-filing system, and thus quick identification of individual animals.  相似文献   

17.
A new species of Tachyoryctes (Mammalia, Rodentia): T. pliocaenicus from the Hadar Formation (Ethiopia) ispresented in this study. It is considered here as an ancestral from T. splendens. Since it also shares characteristics with fossil Rhizomyidae (Kanisamys) from Asia, this species may represent a direct descendant of the latter and would have immigrated to East Africa before the middle Pliocene. This interpretation would agree with the attribution of the genus Tachyoryctes to the family Rhizomyidae. Moreover, the Hadar Paleoenvironment is partially reconstitued from data pertaining to the ecology of T. splendens.  相似文献   

18.
Eric Buffetaut 《Geobios》1981,14(6):815-819
A small crocodilian skull from the lower Portlandian (Cyrena rugosa beds) of Brauvilliers (Meuse) is referred to an atoposaurid of the genus Alligatorium, apparently closely related to the species A. paintenense from the Tithonian of Franconia. It is the first reportof one of these small continental crocodilians from north-eastern France.  相似文献   

19.
G. Bouvrain 《Geobios》1977,10(5):743-746
Among the two bovid genera represented in the turolian locality Mistrals I, Gazella and Miotragocerus, the most abundant is a gazelle which, after comparison with Gazella deperdita from the Mont-Luberon, turns out to belong to this species. Resemblances between the two faunas, already noticed in the study of the Hipparions, are thus comfirmed.  相似文献   

20.
The thermal decomposition of methyl 4,6-O-benzylidene-2,3-di-O-[(methylthio)-thiocarbonyl]-α-d-glucopyranoside afforded methyl 4,6-O-benzylidene-2-thio-α-d-mannopyranoside 3-O,2-S-(S,S-dimethyl trithioorthocarbonate) and methyl 4,6-O-benzylidene-3-thio-α-d-allopyranoside 2-O,3-S-(S,S-dimethyl trithioorthocarbonate) in good yield. This decomposition can be generalized to 1,3-diols derived from sugars. Thus methyl 2,3-di-O-methyl-4,6-di-O-[(methylthio)thiocarbonyl]-α-d-glucopyranoside afforded in the same way the corresponding trithioorthocarbonates, following a regioselective process. The structures of these trithioorthocarbonates are confirmed by spectral and chemical proofs.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号