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1.
Since 1956 were Western Lowland Gorillas (Gorilla gorilla gorilla) kept in Berlin Zoo, counted in the period after 1945. The first offspring was born in 1964. Up to now 9 Gorillas were born in Berlin Zoo, of which 8 were raised, some of them artificial. The oldest Gorilla is “Fatou”, she is now in an age of 53.  相似文献   

2.
Mammals with more rapid and agile locomotion have larger semicircular canals relative to body mass than species that move more slowly. Measurements of semicircular canals in extant mammals with known locomotor behaviours can provide a basis for testing hypotheses about locomotion in fossil primates that is independent of postcranial remains, and a means of reconstructing locomotor behaviour in species known only from cranial material. Semicircular canal radii were measured using ultra high resolution X-ray CT data for 9 stem primates (“plesiadapiforms”; n = 11), 7 adapoids (n = 12), 4 omomyoids (n = 5), and the possible omomyoid Rooneyia viejaensis (n = 1). These were compared with a modern sample (210 species including 91 primates) with known locomotor behaviours. The predicted locomotor agilities for extinct primates generally follow expectations based on known postcrania for those taxa. “Plesiadapiforms” and adapids have relatively small semicircular canals, suggesting they practiced less agile locomotion than other fossil primates in the sample, which is consistent with reconstructions of them as less specialized for leaping. The derived notharctid adapoids (excluding Cantius) and all omomyoids sampled have relatively larger semicircular canals, suggesting that they were more agile, with Microchoerus in particular being reconstructed as having had very jerky locomotion with relatively high magnitude accelerations of the head. Rooneyia viejaensis is reconstructed as having been similarly agile to omomyids and derived notharctid adapoids, which suggests that when postcranial material is found for this species it will exhibit features for some leaping behaviour, or for a locomotor mode requiring a similar degree of agility.  相似文献   

3.
The leaf essential oils of 10 species of Ocotea (Lauraceae) from Monteverde, Costa Rica (Ocotea floribunda, Ocotea holdridgeana, Ocotea meziana, Ocotea sinuata, Ocotea tonduzii, Ocotea valeriana, Ocotea veraguensis, Ocotea whitei, and two undescribed species, Ocotea new species “los llanos”, and Ocotea new species “small leaf”) have been obtained by hydrodistillation and analyzed by GC–MS in order to discern the differences and similarities between the volatile chemical compositions of these species. The principal common constituents of the 10 species of Ocotea were α-pinene, β-pinene, β-caryophyllene, and germacrene-D.  相似文献   

4.
Mexican material referable to Merychippus from two localities in eastern Oaxaca was described first nearly 50 years ago. Subsequent work there and in Central Oaxaca, spanning some 30 years, has allowed to establish the detail stratigraphy in both regions, and assembled a collection of merychippine material from the Matatlán (Central Oaxaca) and El Camarón (eastern Oaxaca) Formations, both K-Ar dated ~15 Ma (late early Barstovian). Detailed taxonomic analysis of this collection indicate the presence of two subhypsodont horse species referable to “Merychippus” cf. “M.” primus and “M.” cf. “M.” sejunctus in both regions. These records document the coexistence in tropical southern North America of basal and hipparionine affinity merychippine grade species, and provide a glimpse in to the diversity of subhypsodont equids in this region.  相似文献   

5.
The fragmentary remains of a juvenile rhabdodontid ornithopod from the Coal-bearing Complex of the Gosau Group (Lower Campanian, Grünbach syncline) at Muthmannsdorf near Wiener Neustadt, Lower Austria are revised. The material, probably belonging to a single individual, includes a right dentary (lectotype of Iguanodon suessi Bunzel, 1871, designated herein), teeth, a fragmentary parietal, fragments of scapula, ?radius, femur, tibia, two vertebrae (lost) and a manual ungual.The lectotype dentary does not provide clear autapomorphies or sufficient diagnostic features to determine its position within the Rhabdodontidae at generic level. By this “Iguanodon suessi” Bunzel, 1871 and the genus “Mochlodon” Seeley, 1881, to which it was latter referred as type species, cannot be characterized sufficiently by differential diagnosis and these are best considered nomina dubia. Based upon combined character comparisons (mainly postcranial features) the Muthmannsdorf ornithopod is referred herein to Zalmoxes Weishampel, Jianu, Csiki and Norman, 2003, a genus so far known from the late Maastrichtian of Romania. It probably but not evidently represents a yet unnamed species, most closely related to Zalmoxes shqiperorum Weishampel, Jianu, Csiki and Norman, 2003. At the present state of knowledge the Austrian material is not further diagnostic at the species level and kept in open nomenclature as Zalmoxes sp.  相似文献   

6.
Laboratory crosses among wild caught individuals of the chromosomal races “atticus” and “thomasi”, were performed to analyze the degree of interracial reproductive isolation. The fertility of the studied specimens was evaluated by taking into consideration the reproductive success, the litter size and performing comparative histological examination of the testicular material. All studied populations were submitted to classical cytogenetic and mitochondrial analysis (cytochrome b gene), providing new evidences to the potential phylogenetic relations and taxonomical status of the two chromosomal races. The previously described “atticus” populations are divided in two genetically distinct, geographically and reproductively isolated lineages (2.9% total and 2.4% net divergence), which probably derived from different glacial refugia of Southern Greece. Here, we suggest that the lineage, consisting of the populations from Attiki and Evia Island, should be distinguished as a valid species, named Microtus atticus, including the two chromosomal races “atticus” and “evia”. On the contrary, the ex-“atticus” populations from North Peloponnesus belong to the same mitochondrial lineage with the other Microtus thomasi populations and should be considered as a chromosomal polymorphism inside the chromosomal race “thomasi”.  相似文献   

7.
Hydrocorals of the genus Millepora are abundant skeleton-forming inhabitants of coral reefs around the world. These species are popularly known as “fire corals” since contact with them causes severe pain, skin eruptions and blisters as a result of the release of unidentified toxins. Millepora species associate with photosynthetic dinoflagellates of the genus Symbiodinium (“zooxanthellae”), and up to now the role of these symbionts in the toxic effects induced by the “fire corals” is unknown. In this study, we compared the hemolytic, vasoconstrictor, and phospholipase A2 (PLA2) activities of the crude aqueous extracts prepared from normal and bleached specimens of two hydrocorals collected in the Mexican Caribbean, Milleporaalcicornis and Millepora complanata. Electrophoretic analysis revealed some differences between the protein profiles of the extracts prepared from normal and bleached specimens. Bleaching decreased, but not abolished, the hemolytic effect induced by the hydrocorals extracts and the phospholipase A2 activity of M. complanata extract. Furthermore, it did not modify the enzymatic activity of M. alcicornis extract and vasoconstriction elicited by both extracts. Our results suggest that the presence of the symbionts does not importantly influence the pharmacological and toxic effects induced by Millepora ssp. extracts, and indicate that cnidarians are the main source of the bioactive compounds.  相似文献   

8.
9.
We have analyzed the relationship between total Zn, Pb and Cu concentrations in the soil and the capacity of three plant species to accumulate these elements in their leaves. The study was carried out in a highly contaminated area at Sulcis-Iglesiente (SW-Sardinia, Italy). We took samples of the leaves of Dittrichia viscosa, Cistus salviifolius and Euphorbia pithyusa subsp. cupanii and samples of the soil beneath each of them at depths of 0-30 and 30-60 cm, both in contaminated mine tailings and surrounding areas. Due to the anthropic origin of the soil materials the results varied considerably. Bioavailability of trace elements was mainly related to the calcium-carbonate content and the crystalline and amorphous forms of iron in the soil. The concentration of Zn in the leaves of the three plant species studied was highest, followed by Pb and finally Cu. The leaves of Dittrichia viscosa contained the highest concentrations of trace elements and this species may be considered as being a “phytoextractor” in soils where the trace-element concentrations are not too high. Euphorbia pithyusa subsp. cupanii had low trace-element concentrations in its leaves despite growing in highly contaminated soils, and so might be used as a “phytostabilizer”. Although Cistus salviifolius does not grow in the most contaminated soils, could be considered as a contamination indicator up to a given level.  相似文献   

10.
Within the framework of a national scientific program named “MORtalités ESTivales de l'huître creuse Crassostrea gigas” (MOREST), a family-based experiment was developed to study the genetic basis of resistance to summer mortality in the Pacific oyster, Crassostrea gigas. As part of the MOREST project, the second generation of three resistant families and two susceptible families were chosen and pooled into two respective groups: “R” and “S”. These two groups of oysters were conditioned for 6 months on two food levels (4% and 12% of oyster soft-tissue dry weight in algal dry weight per day) with a temperature gradient that mimicked the Marennes-Oléron natural cycle during the oyster reproductive period. Oyster mortality remained low for the first two months, but then rapidly increased in July when seawater temperature reached 19 °C and above. Mortality was higher in “S” oysters than in “R” oysters, and also higher in oysters fed the 12% diet than those fed 4%, resulting in a decreasing, relative order in cumulative mortality as follows; 12% “S” > 12% “R” > 4% “S” > 4% “R”. Although the observed mortality rates were lower than those previously observed in the field, the mortality differential between “R” and “S” oysters was similar. Gonadal development, estimated by tissue lipid content, followed a relative order yielding a direct, positive relationship between reproductive effort and mortality as we reported precedently by quantitative histology. Regarding hemocyte parameters, one of the most striking observations was that reactive oxygen species (ROS) production was significantly higher in “S” oysters than in “R” oysters in May and June, regardless of food level. The absence of known environmental stress under these experimental conditions suggests that the ROS increase in “S” oyster could be related to their higher reproductive activity. Finally, a higher increase in hyalinocyte counts was observed for”S” oysters, compared to “R” oysters, in July, just before mortality. Taken together, our results suggest an association of genetically based resistance to summer mortality, reproductive strategy and hemocyte parameters.  相似文献   

11.
Lycaon pictus has been named by a variety of common names, such as “African Wild Dog”, “African Hunting Dog” and their adequates in other languages. The article summarizes the history of naming in that species concluding with a new recommendation by the SSP as well as the EEP for that species to rename it as Painted Dog. As the translation of that name into German is an unhandy term it is suggested to name it “Picasso-Hund” in that language.  相似文献   

12.
The green blowfly species Lucilia cuprina and Lucilia sericata are economically important pests for the sheep industries of Australia and New Zealand. L. cuprina has long been considered a good target for a genetic pest management program. In addition, L. sericata maggots are used in the cleaning of wounds and necrotic tissue of patients suffering from ulcers that are difficult to treat by other methods. Development of efficient transgenesis methods would greatly facilitate the development of strains ideal for genetic control programs or could potentially improve “maggot therapy”. We have previously reported the germ-line transformation of L. cuprina and the design of a “female killing system” that could potentially be applied to this species. However, the efficiency of transformation obtained was low and transformed lines were difficult to detect due to the low expression of the EGFP marker used. Here we describe an efficient and reliable method for germ-line transformation of L. cuprina using new piggyBac vector and helper plasmids containing the strong promoter from the L. cuprina hsp83 gene to drive expression of the transposase and fluorescent protein marker gene. We also report, for the first time, the germ-line transformation of L. sericata using the new piggyBac vector/helper combination.  相似文献   

13.
Improved yield and biological efficiency (BE) of Pleurotus eryngii var. eryngii were achieved by supplementation of substrate with a commercial delayed-release nutrient and use of a casing overlay. Yield increases of 14% were achieved from cased substrates that were supplemented at time of casing with delayed-release nutrient (Remo’s). Use of a casing layer enhanced yield by 141% over non-cased substrates. When casing and substrate supplementation were combined, yield increased 179% over non-cased/non-supplemented substrates. Mushrooms harvested from cased substrates were darker in color and solids contents were lower compared to non-cased substrates. An additional break of mushrooms was harvested from non-cased “spent” substrate by fragmenting and re-supplementing the substrate prior to the application of a casing overlay. Three production methods were compared for their effect on mushroom yield: “standard”, “casing” and “casing after first break”. Casing of the substrate before first break (“casing” production method) resulted in the highest yield and biological efficiency.  相似文献   

14.
A broad multilocus phylogenetic analysis (MLPA) of the representative diversity of a genus offers the opportunity to incorporate concatenated inter-species phylogenies into bacterial systematics. Recent analyses based on single housekeeping genes have provided coherent phylogenies of Aeromonas. However, to date, a multi-gene phylogenetic analysis has never been tackled. In the present study, the intra- and inter-species phylogenetic relationships of 115 strains representing all Aeromonas species described to date were investigated by MLPA. The study included the independent analysis of seven single gene fragments (gyrB, rpoD, recA, dnaJ, gyrA, dnaX, and atpD), and the tree resulting from the concatenated 4705 bp sequence. The phylogenies obtained were consistent with each other, and clustering agreed with the Aeromonas taxonomy recognized to date. The highest clustering robustness was found for the concatenated tree (i.e. all Aeromonas species split into 100% bootstrap clusters). Both possible chronometric distortions and poor resolution encountered when using single-gene analysis were buffered in the concatenated MLPA tree. However, reliable phylogenetic species delineation required an MLPA including several “bona fide” strains representing all described species.  相似文献   

15.
Fluorescent timers are useful tools for studying the spatial and temporal cellular or molecular events. Based on the trans-splicing mechanism in Caenorhabditis elegans, we constructed a “fluorescent timer” through bicistronic expression of two fluorescent proteins with different maturation times. When used in vivo, this “timer” changes its color over time and therefore can be used to monitor the activity of the targeted promoters in C. elegans. Using this “timer”, we have successfully traced the time-dependent activity of myo-3 promoter which drives expression in body wall muscle and vulval muscle. We found that the myo-3 promoter started to be active about 7 h after egg-laying and sustained its activity in the following hatching process. We have also determined the myo-3 promoter activity during larval development by this “timer”. We anticipate that more new “fluorescent timers” with variable time-resolution could be designed by bicistronic expression of different fluorescent protein pairs.  相似文献   

16.
17.
Traditionally, zooplankton studies have been carried out on larger species and later developmental stages, at least in the case of copepods. This fact is due to the difficulty of distinguishing between all the morphologically very similar species and genus, especially at immature stages. Nowadays, however molecular techniques allow us to discriminate these species easily. We have developed a RFLP (Restriction Fragment Length Polymorphism) technique to distinguish between the species of the genus Clausocalanus which are present at our study zone, the Central Cantabrian Sea. This genus belongs to the “small” fraction of mesozooplankton (500-200 μm), and it has been scarcely studied even though it is an important component of the mesozooplankton. This technique allows identification of individuals and from small body parts.  相似文献   

18.
It has been suggested that bacteria associated with soft-bodied organisms are suggested to produce bioactive compounds against the attachment of invertebrate larvae and bacteria onto the surface of these organisms. Our recent study has demonstrated that epibiotic bacteria from the surface of the soft coral Dendronephthya sp. (Coelenterata: Octocoralia, Alcyonacea) inhibit the growth of bacteria commonly found in marine natural biofilms. In the present study, the effect of 11 epibiotic bacteria isolated from the surface of Dendronephthya sp. on larval settlement of the tubeworms Hydroides elegans was examined using laboratory bioassay. Among 11 bacterial isolates, 2 strains (18%) inhibited the larval settlement of H. elegans (Haswell), 4 strains (36%) were “inductive” to larvae and the remaining 5 strains (46%) were “non-inductive”. There was no correlation between the antifouling activities of bacterial isolates and their phylogenetic origin, i.e. closely related bacterial strains showed different effects on larval settlement of H. elegans. When all “inductive”, “non-inductive” and “inhibitive” bacterial isolates were mixed in a 1:1:1 ratio, the effect of the resultant multispecies film on larval settlement became “inhibitive”. Waterborne compounds of Vibrio sp. and an unidentified α-Proteobacterium, which suppressed the settlement of H. elegans and Bugula neritina (L.) larvae, were further investigated using size fractionation and bioassay-guided enzymatic analysis. It was found that antilarval settlement compounds from these bacteria were heat-stable polysaccharides with a molecular weight >100 kDa. The results indicate that the bacteria associated with the soft coral Dendronephthya sp. may contribute to the antifouling mechanisms of the soft-bodied organisms by producing compounds that are against bacterial growth and settlement of macrofoulers on the surface of their host.  相似文献   

19.
A phylogenetic analysis of Bambusa and allies based on the plastid DNA non-coding regions rps16-trnQ, trnC-rpoB, trnH-psbA and trnD-T, and a partial nuclear GBSSI gene, was carried out. This included representatives from all four Bambusa subgenera (including type species), a group of segregate Southeast Asian genera distinctive by their climbing–scrambling culms (Dinochloa, Holttumochloa, Kinabaluchloa, Maclurochloa, Soejatmia, Sphaerobambos), and two other Bambusinae genera (Dendrocalamus, Gigantochloa). The results do not support the present subgeneric classification of Bambusa. The climbing Southeast Asian genera, all of which include species previously placed in Bambusa, are distinct from the “core Bambusa group” (type species and alliance) and the Bambusa complex generally.  相似文献   

20.
Most medicinal plants used against malaria in endemic areas aim to treat the acute symptoms of the disease such as high temperature fevers with periodicity and chills. In some endemic areas of the Brazilian Amazon region one medicinal plant seems to be an exception: Ampelozyziphus amazonicus, locally named “Indian beer” or “Saracura-mira”, used to prevent the disease when taken daily as a cold suspension of powdered dried roots. In previous work we found no activity of the plant extracts against malaria blood parasites in experimentally infected animals (mice and chickens) or in cultures of Plasmodium falciparum. However, in infections induced by sporozoites, chickens treated with plant extracts were partially protected against Plasmodium gallinaceum and showed reduced numbers of exoerythrocytic forms in the brain. We now present stronger evidence that the ethanolic extract of “Indian beer” roots hampers in vitro and in vivo development of Plasmodium berghei sporozoites, a rodent malaria parasite. Some mice treated with high doses of the plant extract did not become infected after sporozoite inoculation, whereas others had a delayed prepatent period and lower parasitemia. Our data validates the use of “Indian beer” as a remedy for malaria prophylaxis in the Amazon, where the plant exists and the disease represents an important problem which is difficult to control. Studies aiming to identify the active compounds responsible for the herein described causal prophylactic activity are needed and may lead to a new antimalarial prophylactic.  相似文献   

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