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Sexual reproduction in yeasts has a survival function by providing an alternative to the vegetative processes when conditions are no longer conducive for growth. If both sexes are in the correct physiological state (usually under starvation conditions), then initiation of copulation involves the mutual induction of a sexual response. This response is mediated by diffusible compounds and by physical contact. Initial cell contacts between opposite mating types can be disrupted easily, but stronger intercellular bonds form later that result in the fusion of two cells into one. Union between mates involves mixing of parental gene pools. The new diploid organism or its subsequent offspring might be better equipped to survive in a new environment because they may contain new combinations of parental genes. Hence, sex is more advantageous to the survival of the species than it is to the individual organism. The purpose of this review is to compare the steps in the mating process in three species of yeasts. The various physiological factors, events and regulatory phenomena that are part of the mating process will be described for Hansenuta wingei, Schizosaccharomyces pombe and Saccharomyces cerevisiae in Sections II, III and IV, respectively. Then, in Section V, the similarities and differences among these yeast systems will be discussed. Emphasis in this article will be on recent observations since reviews of earlier work are available for each mating system (for H. wingei: Crandall and Brock, 1968; Crandall and Caulton, 1975; for Schizosacch. pombe: Leupold, 1970; Gutz et at., 1974; for Sacch. cerevisiae: Fowell, 1969a, b; Bilinski et at., 1975; Sena et at., 1975). For a comprehensive review of conjugation in all yeasts, fungi and other micro-organisms, consult Crandall (1977). The three yeasts to be reviewed here are quite diverse in terms of their ecological niches, metabolism, morphology and life cycles. Therefore, for a better understanding of the physiology of sexual reproduction in these organisms, it is necessary first to consider these characteristics. A more detailed description of each yeast is given in Lodder (1970).
A synthesis of the Carabid fauna of the Central and Eastern Alps and Pre-Alps, from a biogeographical point of view, is presented. Only the Italian side of the Alpine chain is considered, from the basin of the Toce river to the Trieste and Gorizia Karst. Main features of the landscape are: 1. an ancient orogenetic history and evolution, that made this area available to the colonization by carabids, of both gondwanaland and laurasian lineages, since the lower Tertiary; 2. a marked geological and geo-morphological complexity, with highest elevation at Pizzo Bernina m 4.049; 3. the presence of a very developed, dolomitic-calcareous and markedly carsified prealpine belt, rich of deep and large hypogean systems (also at high altitude), which makes this area highly different, from the geo-morphological point of view, from the Western Alps; 4. the geographic position, as a mountain chain of some 750 kms between central Europe and the Padanian plain, connected with the Caravanche and the Dinaric chain and close to the Adriatic sea in me Eastern part; 5. finally, a puzzled climate situation, that includes xero-thermic areas (500-700 mm of rain per year, also in some intra-alpine sectors), close to highly rainy areas - more than 2.500 mm per year - in the westernmost and easternmost parts of the chain. Thus, like in the Western Alps, sub-mediterranean vegetation types, dose to cool-moist forests, coexist with high-altitude environments above the timber line. These facts explain the heterogeneity, the richness, the variety, and the interest of the carabid fauna of the area: the highest number of species (658) ascertained so far, i.e. 112 of the whole Italian carabid fauna and about 115 of the carabid fauna cited so far for the Europe in politic sense, fi·om me Canary islands to the Urals; the high number of euri- or stenoendemites (204, i.e. abour 31 % of the species, 3/5 of which concentrated in the pre-alpine belt), and the complex origins and/or affinities of different taxa. A large number of species (174, i.e. 26%) belongs to European chorotypes (European, South-European or typically Alpine), and even more (255, i.e. 38%) to Holarctic (Holarctic, Palaearccic, West-Palaearctic, Asiatic-European, Siberian-European, Central-Asiatic-European, Central-Asiatic-European-Mediterrancan, Turanic-European, Turanic-EuropeanMediterranean, European-Mediterranean) chorotypes. This darum confirms the well known role, both of connection and separation, that the Alps as a whole played between Europe and the Mediterranean area. Furthermore, it is to be recalled the presence, in some localities of the Eastern Alps, of micro thermophilous, boreal species, like Miscodera arctica, now widespread in Northern regions of the Holarctic Region. Many orophilous, forest-dwelling, riparian and hygrophilolls species, are of northern, north-eastern, ruranic or dinaric-balkanian origin. A very small, bur interesting group of thermophilous elements (mostly Harpalini), originally from the Mediterranean area or temperate steppes, during the hypsothermic periods of the Pleistocene and Olocene, reached the Central and Eastern Alps and Pre-Alps, and persist in xerothermlc biotopes. Some of these could increase their range of distribution as a consequence human activities in agricultural use overgrazing and deforestation. Some others, like Carabus montivagus and Laemostenus algerinus, seem to be present owing to very recent anthropogenic introduction. From the biogeograpic point of view, however the most important group of species is represented by the impressive number of endemics (204, of which 116 species restricted to politic Italy), either eurendemics to Central and Eastern Alps and Pre-Alps, or stenoendemics to single sectors of the area or to very small biotopes (caves, isolated montane massifs): among these, we may cite some large-sized species like Cychrus cylindricollis, endemic at high altitude, to the Central Pre-Alps, several montane, very localized Trechus species, many subterranean, highly specialized Trechini of the peculiar genera Boldoriella, Orotrechus, Anophthalmus, Allegrettia, Italaphaenops, Lessinodytes: many Pterostlchini, and others, Most of them must be considered as pre-Quaternarian elements, With affinltl,es either til Gondwana (such as the blind Reicheina of the genus Alpiodytes), or in the Angarian (as the Broscosoma species) areas, They are, the result of an ancient, subtropical or temperate forest dweller Carabid fauna, tied now to soil: forest littter, superficlal subterranean environment, caves, and upper montane refugia, Both from floristic and faunistic informatlon, It IS a well known fact that the pre-alpine belt as a whole represents a large, unique Pleistocene refugium, that shows a scenario of marked isolation and speciation in mountains, valleys and hypogean compartments. The analysis of the entire Carabid fauna in the Central and Eastern Alps and Pre-Alps shows that the present composition and complexity is the result both of ancient clado-vicariance events and of recellt, ecological factors, These facts surprisingly make this area (not only concerning carabids) very close to important towns and to one of the most populated, cultivated and industrialized area of Italy (the Padanian plain), and in spite of its relatively small surface, one of the most important hot spar of biodiversity in Europe, in which many biotopes are presently highly endangered, or in some cases completely destroyed, A checklist of the Carabid species of the Central and Eastern Alps and Pre-Alps, with their chororypes, is added.
The Invertebrate section of the Museum of Zoology QCAZ at the Pontifical Catholic University of Ecuador in Quito maintains nearly two million curated specimens, and comprises Ecuador's largest collection of native taxa. We review 1902 type specimens from 6 subspecies and 320 species in 121 genera and 42 families, currently kept in the Museum. The list includes 116 holotypes, 10 allotypes, 1774 paratypes and 2 neoparatypes. The collection of type specimens is particularly strong in the Coleoptera (family Carabidae and Staphylinidae) and Hymenoptera. However, other insect orders such as Diptera and Lepidoptera and non-insect arthropods such as Acari, Aranea and Scorpiones, are moderately represented in the collection. This report provides original data from labels of every type specimen record. An analysis of the geographic distribution of type localities showed that collection sites are clustered geographically with most of them found. towards the northern region of Ecuador, in Pichincha, Cotopaxi and Napo provinces. Sites are mainly located in highly accessible areas near highways and towns. Localities with a high number of type species include the cloud forest reserve Bosque Integral Otonga and Parque Nacional Yasunf in the Amazon rainforest near PUCE's Yasuni Scientific Station. Type localities are not well represented in the Ecuadorian National System of Protected Areas. Future fieldwork Sllould include. localities in the southern region of Ecuador but also target less accessible areas not located near highways or towns. We discuss the value of the collection as a source of information for conservation and biodiversity policies in Ecuador.
Gli Autori presentano i risultati preliminari dello studio interdisciplinare (geostratigrafia e paleopedologia; palinologia; malaccfaune; faune mammologiche; industrie; datazioni raiometriche) dei depositi würmiani, fortemente antropizzati, del Riparo Tagliente in Valpantena (Monti Lessini). I depositi più antichi, riferibili al I Pleniglaciale wiirmiano e alla parte iniziale del Würm medio, contengono industrie del Paleolitico Medio e della fase arcaica del Paleolitico Superiore (Aurignaziano a dufours). Una fase erosiva, la deposizione di ghiale fluviali all'esterno del riparo e fenomeni di geliflusso sono riconducibili al II Pleniglaciale würmiano. I depositi più recenti, riferibili al Tardiglaciale (dal Dryas antico all'oscillazione di Alleriöd), hanno dato industrie dell'Epigravettiano italico finale e altri resti di occupazione antropica del riparo (strutture di abitato, oggetti ornamentali, una sepoltura, opere d'arte). Le sequenze di industrie musteriane cd epigravcttianc del Riparo Tngliente costituiscono attualmente il punto di riferimento fondamentale per lo studio dei complessi del Paleolitico Medio e della fine del Paleolitico Superiore nell'Italia nordorientale.
The impact of naval sonar on beaked whales is of increasing concern. In recent years the presence of gas and fat embolism consistent with decompression sickness (DCS) has been reported through postmortem analyses on beaked whales that stranded in connection with naval sonar exercises. In the present study, we use basic principles of diving physiology to model nitrogen tension and bubble growth in several tissue compartments during normal div ng behavior and for several hypothetical dive profiles to assess the risk of DCS. Assuming that normal diving does not cause nitrogen tensions in excess of those shown to be safe for odontocetes, the modeling indicates that repetitive shallow dives, perhaps as a consequence of an extended avoidance reaction to sonar sound, can indeed pose a risk for DCS and that this risk should increase with the duration of the response. If the model is correct, then limiting the duration of sonar exposure to minimize the duration of any avoidance reaction therefore has the potential to reduce the risk of DCS.
Im Jahre 1932 wurden 4 Beobachtungen über Strömungen im Schwarzen Meere (Meerbusen Mamaia) mit folgendem Ergebnis angestellt: 1. Zwischen 24. Juni und 2. Juli wurde eine S.N.-Strömung beobachtet, deren Wasser am 26. Juni in den Meerbusen Mamaia eindrang und da ein plötzliches Temperatursinken um 8,40 C hervorrief. Die Fischbevölkerung änderte sich ebenso rasch, da mit dem kalten Wasser grosse Exemplare von Mugil cephalus, Temnedon saltator und Trachurus trachurus an der Stelle der sonst täglich an der Küste angetroffenen Fische traten. 2. Zwischen 5. und 12. Juli wurde eine Verminderung der Dichte von 1,010 auf 1,005 binnen 24 Stunden bei fast gleichbleibender Wassertemperatur festgestellt. Parallel mit der Verminderung des Salzgehaltes wurden im Meere grosse Mengen Süsswasserfische, besonders Karpfen, die aus der Donaugegend stammten, gefischt; andererseits warfen die Wellen Zweige und Wurzeln von Weidebäumen an die Küste. Diese Erscheinungen sprechen für das Vorhandensein einer N.S.-Strömung, die in dieser Zeit in den Mamaiaer Meerbusen einströmte. 3. In der Zeitspanne 22. August - 18. September wurde die N.S.-Strömung wieder beobachtet, da sie eine abermalige Verminderung des Salzgehaltes im Meerbusen herbeiführte. Am 23. August wurde die Hauptströmung zirka 10 km. vor Constantza, in der Gegend der 20-25 m. Tiefenlinie gefunden (bei 27° C war die Dichte 1,005). Durch langanhaltende und wiederholte N.O.- und O.-Winde wurde das warme Wasser der N.S.-Strömung in den Meerbusen Mamaia getrieben, sodass dort am 11. September das Dichteminimum von 1,0039 bei 22,5° C erreicht wurde. 4· Schliesslich wurde zwischen 31. Oktober und 7. November ein Eindringen von kaltem Wasser in denselben Meerbusen beobachtet, das ein plötzliches Temperatursinken von 16° C auf 6,50 C bei fast gleichbleibenden Dichtewerten zur Folge hatte. Dieses kalte Wasser gehörte der S.N.-Strömung an, denn wir stellten in dieser Zeit fest, dass die Stellnetze 100-.300 m. weit nordwärts von ihrem Platze getrieben wurden . Der Fischfang zeigte sich ergiebig zwischen 15,5° C und 8° C., während bel 6,5° C die Makrelen, die vorher in grossen Mengen gefangen wurden, ausblieben.
The siliceous claystone and chert lithologic units of the Triassic-Jurassic chert-clastic sequence are well exposed in the Inuyama, Mt. Kinkazan and Hisuikyo areas of the southeastern Mino Terrane. Twenty-one continuous sections from those areas were investigated in order to establish comprehensive radiolarian biozones and clarify the successive lithologic changes through the Triassic and lowest Jurassic. Twenty new radiolarian zones are established; the lowest two are assemblage zones and the others are defined by the first or last occurrence of index taxa. The definitions are as follows in chronological order: TR 0, Follicucullus Assemblage Zone (early Spathian or older); TR 1, Parentactinia nakatsugawaensis Assemblage Zone (late Spathian); TR 2A, Eptingium nakasekoi Lowest-occurrence Zone (early Anisian); TR 2B, Triassocampe coronata group Lowest-occurrence Zone (early Anisian); TR 2C, Triassocampe deweveri Lowest-occurrence Zone (late Anisian); TR 3A, Spine A2 (possiblly derived from Oertlispongus inaequispinosus) Lowest occurrence Zone (late Anisian) ; TR 3B, Yeharaia elegans group Lowest-occurrence Zone (early Ladinian); TR 4A, Muelleritortis cochleata Lowest-occurrence Zone (late Ladinian); TR 4B, Spongoserrula dehli Lowest-occurrence Zone (late Ladinian to early Carnian); TR 5A, Capnuchosphaera Lowest-occurrence Zone (early Carnian); TR 5B, Poulpus carcharus sp. nov. Lowest-occurrence Zone (early to late Carnian); TR 6A, Capnodoce- Trialatus Concurrentrange Zone (late Carnian to early Norian), TR 6B, Trialatus robustus-Lysemelas olbia gen. et sp. nov. Partial-range Zone (early Norian); TR 7, Lysemelas olbia gen. et sp. nov. Lowest-occurrence Zone (early to late Norian); TR 8A: Praemesosaturnalis multidentatus group Lowest-occurrence Zone (late Norian); TR 8B: Praemesosaturnalis pseudokahleri sp. nov. Lowest-occurrence Zone (late Norian) ; TR 8C: Skirt F (possiblly derived from Haeckelicyrtium takemurai) Lowest-occurrence Zone (late Norian to early Rhaetian); TR 8D: Haeckelicyrtium breviora sp. nov. Taxon-range Zone (early to late Rhaetian) ; JR OA: Haeckelicyrtium breviora sp. nov.-Bipedis horiae sp. nov. Partial-range Zone (Hettangian); and JR OB: Bipedis horiae sp. nov. Lowest-occurrence Zone (Hettangian/Sinemurian) . These zones are correlated to previousy established radiolarian assemblages and zones in Japan and other regions. Age assignment of the zones is also discussed on the basis of the correlation and other available chronological data. The original stratigraphic succession of the Triassic in the studied area, which ranges in age from Early Triassic to Early Jurassic, is more than 100 m in thickness and can be reconstructed in detail. The succession is subdivided into seven units based on lithologic features. Each unit was probably accumulated under a particular sedimentary condition, thus successive changes of paleoceanographic environments during Triassic time can be traced continuously. Nine new genera including Ayrtonius, Blonzella, Braginella, Bulbocampe, Enoplocampe, Lysenzelas, Parvibrachiale, Spongoxystris and Veles, and 47 new species are described herein. A comprehensive list of identified taxa is presented.