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1.
Zusammenfassung Die Mauserperiode westspanischer Weidensperlinge(Passer hispaniolensis) und Haussperlinge(P. domesticus) reicht von Ende Juli bis Ende September/Anfang Oktober. Beim Weidensperling endet der Federwechsel im Durchschnitt etwa fünf Tage früher als beim Haussperling. Es gibt keine Geschlechtsunterschiede in der Chronologie der Mauser beim Weidensperling. Ad. beider Arten mausern schneller und synchronisierter als juv., die ihr Gefieder um so rascher erneuern, je später sie mit der Mauser begonnen haben. Die Handschwingenmauser dauert etwa 66 Tage beim Weidensperling und 69 Tage beim Haussperling. Beide Arten brauchen ca. 3 weitere Tage für die Verhornung der 5. und 6. Armschwingen. Die ad. beider Arten und die juv. Weidensperlinge beginnen die Mauser im Durchschnitt am selben Tag (24. Juli), die juv. Haussperlinge später (29. Juli). Der Mauserverlauf und die Beziehungen zwischen den verschiedenen Federreihen sind bei beiden Arten identisch. Die Synchronisation der Mauser ist beim Weidensperling höher. Brut und Mauserperiode überschneiden sich beim Haussperling; beim Weidensperling, bei dem noch kurze Wanderungen gleich nach der Fortpflanzungsperiode und vor der Mauser erfolgen, nicht. Das frühere und höher synchronisierte Mauserende beim Weidensperling scheint eine Anpassung an die stärkere Zugtendenz zu sein.
On the moult of Spanish Sparrows(Passer hispaniolensis) and House Sparrows(Passer domesticus) in Iberia
Summary The moulting period of Spanish sparrows(Passer hispaniolensis) and House Sparrows(Passer domesticus) in Western Spain extends from late July to late September/early October. House Sparrows finish moulting on average some five days later than Spanish Sparrows. There are no sexual differences in the moulting chronology of adult Spanish Sparrows. Ad. of both species moult faster and better synchronized. The speed of moulting is also higher in later moulting juveniles. The estimated durations of wing feather replacement were 66 days for the Spanish Sparrow and 69 days for the House Sparrow. Some three more days are needed to complete the growth of the 5th and 6th secondary remiges in both species. Adults of both species and juvenile Spanish Sparrows start moulting on average on the same date: 24th July; juvenile House Sparrows start moulting on 29th July. The sequence of moult and the relations between different feather tracts are identical in both species. The synchronization of the moult is higher in the Spanish Sparrow. Breeding and moulting seasons slightly overlap in the House Sparrow, but not in the Spanish Sparrow. In this species the time lapse between both periods allows the birds to wander to suitable areas, where they moult. The earlier ending and higher synchronization of the moult in the Spanish Sparrow is related to its higher migratory tendency.
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2.
Zusammenfassung In einem Gebiet auf der Schwäbischen Alb von 432 km2 mit weitgehend homogener Waldverteilung brüteten 13 Habicht- und 20 Rotmilanpaare. Die Horsthöhe über dem Boden lag bei beiden Arten oberhalb der Handbuchangaben. Eine Bevorzugung von Laubwaldhabitaten durch den Rotmilan war nicht erkennbar. Die regelmäßige intraspezifische Dispersion der Horstreviere beider Arten läßt auf das Vorhandensein intraspezifischer Territorialität schließen. Eine Regelmäßigkeit in der interspezifischen Dispersion war hingegen nicht erkennbar. Negative Einflüsse des Habichts auf den Reproduktionserfolg des Rotmilans waren ebenfalls nicht nachweisbar. Konkurrenz um Horstplätze zwischen Habicht und Rotmilan spielte im untersuchten Gebiet somit eine unbedeutende Rolle. Die Wirkung solcher Konkurrenz als ein für konstante Populationen allgemeingültiger Regulationsmechanismus nachKostrzewa et al. (1985) wird in Frage gestellt. Allein im Abstand des Horstes zum Waldrand bestand im Untersuchungsgebiet eine klare Trennung der Horstplatzansprüche beider Arten.
Nesting habitat and territoriality in Goshawk (Accipiter gentilis) and Red Kite (Milvus milvus)
Summary Intraspecific and interspecific spacing of Goshawk and Red Kite nesting places were investigated in an area of 432 km2 located in southern Germany. The area is characterized by a relatively homogeneous forest distribution. Nesting habitat data were collected over a period of four years. Thirteen breeding pairs of Goshawk und twenty breeding pairs of Red Kite were censused within the study area. The mean heights of nests above ground in both species were greater than those previously described (i. e.Cramp &Simmons 1980). The current view, that Red Kites prefer deciduous forest nesting habitats and deciduous nest trees, could not be confirmed.The regular intraspecific spacing of nesting places in both species indicates intraspecific territoriality. In contrast, no regularity in interspecific spacing could be detected. There was no noticeable influence of the Goshawk on the reproduction success of the Red Kite. Thus, competition for nesting places in the investigated area among Goshawk and Red Kite plays, if any, only a minor role. A factor seperating the two species with high significance is the distance from the nesting place to the nearest forest edge.In conclusion, the present study shows that competition for nesting places as a regulation mechanism, as proposed byKostrzewa et al. (1985), is unlikely.
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3.
Summary A male bird of the F1-generation of a successful hybridization experiment between House Sparrows(Passer domesticus) and Spanish Sparrows(Passer hispaniolensis) exhibited intermediate phenotypical characters between both parental species, being similar to a Nord-African flückigeri-type Sparrow.  相似文献   

4.
Zusammenfassung Mit einer konstanten Wachstumsrate K von 0,444 und 0,481 wachsen Blaukehlkolibris (Lampornis clemenciae; Körpermasse 7,5 g) ähnlich schnell wie andere Vogelarten der gemäßigten Zone (K = 0,384–0,680). Der t10–90-Wert der beiden untersuchtenLampornis-Nestlinge beträgt 9,1 bzw. 9,9 Tage. Die Körpertemperatur kann am 10. Tag reguliert werden. Am Ende der Nestlingszeit erreicht die Schnabellänge der Jungvögel 90 % der eines Adultvogels. Die Morphogenese entspricht den Beobachtungen beim kleineren ZimtkolibriSelasphorus rufus.
Morpho- and thermogenesis in nestling Blue-throated Hummingbirds (Lampornis clemenciae)
Summary The study was conducted at the Southwestern Research Station of the American Museum of Natural History (N. Y.) in June/July 1981. Cumulative growth, thermogenesis, monitored in one chick only, morphogenetic characters and behavioral patterns in 2 nestlings were constantly recorded from hatching to fledging. The growth rate K and the inverse growth rate t10–90 (s. Fig.) are presented for both nestlings. Until the 9th day both nest-mates accumulated 67 % and 86 % respectively of their maximum weight (asymptote). The data suggest, as already observed inSelasphorus rufus, another temperate trochilid, that growth rates extend those of tropical species, e.g.Amazilia sp. (seeRicklefs 1976). However, further data are needed to confirm this geographical trend for hummingbirds.Thermogenetical homeostasis was observed in one chick at an age of 10 days. Simultaneously, the shafts of primaries appeared in both chicks after 7 days, the eyes opened at the 9th day, primaries are completely open at the 13th day. Wing exercises were observed at the 20th day, and both nestlings fledged at an age of 25 days. The bill length by then is 90 % of an adult bird.
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5.
Zusammenfassung Mittels der Atomabsorptionsspektroskopie wurden Lebern, Nieren und Federn von Graureihern und von diesjährigen Kormoranen auf Cadmium und Blei untersucht.Cadmium war in Geweben der Kormorane höher konzentriert als in gleichaltrigen Graureihern (Leber 0,063 bzw. 0,039, Niere 0,113 bzw. 0.104 mg/kg Frischmasse; Federn 0,077 bzw. 0,025 mg/kg Trockenmasse). Dies könnte auf unterschiedliche Nahrung oder unterschiedliche physiologische Situation der Vögel zurückzuführen sein. Als Maximum wurden in der Niere eines Kormorans 0,375 mg/kg gemessen. Bei den Graureihern konnte in Lebern und Nieren eine Altersakkumulation erkannt werden. Blei war in den Geweben beider Arten unterschiedlich hoch konzentriert. Kormorane enthielten in Lebern 0,124 und in Nieren 0,147 mg/kg Frischmasse sowie in Federn 0,442 mg/kg Trockenmasse, Graureiher 0,110, 0,157 bzw. 0,739 mg/kg. Die höchsten Konzentrationen wurden in Federn gemessen und betrugen bei einem Graureiher 4,525 mg/kg. Eine Altersakkumulation konnte bei Graureihern in Lebern nachgewiesen werden. Zusammenhänge zwischen Feder- und Organbelastungen wurden nur bei diesjährigen Graureiher- erkannt: Federcadmium und Lebercadmium korrelierten positiv miteinander.
Heavy metals in tissue and feathers of Grey Herons (Ardea cinerea) and Cormorants (Phalacrocorax carbo sinensis)
Summary The livers, kidneys and feathers of 40 Grey Herons and 20 Cormorants were investigated by AAS to determine the extent of contamination with cadmium and lead. The birds had been shot in autumn 1979–1986 in Schleswig-Holstein. All results are given in mg/kg (ppm) wet mass (liver, kidney) or dry weight (feather). On the average, the contamination by cadmium in the livers (0.063), kidneys (0.113) and feathers (0.077) was higher in Cormorants than in Grey Herons (0.039, 0.104 and 0.025). These differences may be the result of different food or physiology. The livers and kidneys of young Grey Herons contained less cadmium than the tissue of older birds. The feathers of male Grey Herons contained more cadmium than feathers of females do. This was also the case in kidneys of male Cormorants as compared to the females. Cadmium values in livers and kidneys were positive correlated. No general tendency was detectable in regards to lead contamination. The results concerning Cormorants were 0.124 (liver), 0.147 (kidney), 0.442 (feather) and concerning Grey Herons 0.110, 0.157 and 0.739. The livers of old Grey Herons were more highly contaminated by lead than livers of young ones. The feathers of male Herons contained two times more lead than the feathers of females do.In general, a concentration of heavy metals in feathers does not indicate a contamination of livers or kidneys. A correlation between the values in feathers and tissue was evident only in one case, where a positive correlation was found between feather- and liver cadmium in young male Grey Herons.
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6.
Work on the exceptionally well-preserved, rapidly accumulating Bath Cliff Section, Barbados and supplementary Deep Sea Drilling Project samples, has revealed the evolutionary origins of three stratigraphically useful species in theCryptoprora ornata Zone straddling the Eocene/Oligocene boundary and demonstrated the origin of the genusCyclampterium. Elucidation of the origin ofCyclampterium milowi necessitates a revision of the generaLophocyrtis andCyclampterium.Lophocyrtis (Lophocyrtis)jacchia is the ancestor ofL. (Cyclampterium)hadra, the earliest member in the subgenusCyclampterium which comprises the anagenetic lineage leading fromL. (C.)hadra toL. (C.)neatum. The monotypic subgenusSciadiopeplus branches off from an early member in theCyclampterium lineage. The new speciesL. (L.)exitelus andL. (S.)oberhaensliae terminate the subgeneraLophocyrtis andSciadiopeplus, respectively. During the investigation it also became clear that morphotypes resembling earlyL. (C.)milowi could be found in mid and high latitude assemblages in the late Early and late Middle Eocene. The origin of one these morphotypes was also traced toL. (Lophocyrtis)jacchia giving rise to the new subgenusParalampterium. This lineage includes the new speciesL. (Paralampterium)dumitricai and two species questionably assigned to it,L. (Paralampterium)?longiventer and the new speciesL. (Paralampterium) ?galenum. The relationship ofL. (P.)dumitricai toL. (P.) ?longiventer andL. (P.) ?galenum is unknown.  相似文献   

7.
Past treatments of the sleeper shark genus Somniosus generally recognize three species: S. microcephalus, S. pacificus, and S. rostratus. Based on morphometrics and meristics, we conclude that this genus includes two subgenera (Somniosus and Rhinoscymnus) and five species. Subgenus Somniosus differs from Rhinoscymnus by being much larger when adult and in having more numerous tooth rows in the lower jaw, hooklike rather than leaf-shaped dermal denticles, more numerous spiral valve and vertebral counts, and a poorly calcified vertebral column. Subgenus Somniosus includes S. (Somniosus) microcephalus and S. (S.) pacificus of the Northern Hemisphere and S. (S.) antarcticus of the Southern Hemisphere. Although Somniosus antarcticus has been synonymized with S. microcephalus and identified as S. pacificus in past literature, it differs from S. microcephalus in having a shorter interdorsal space, a more posterior first dorsal fin, lower dorsal fins, more numerous tooth rows in the lower jaw, more numerous spiral valve counts, and fewer precaudal vertebrae. Somniosus antarcticus also differs from S. pacificus by having a shorter prebranchial length, lower dorsal fins, more numerous spiral valve counts, and slightly more precaudal vertebrae. Subgenus Rhinoscymnus includes S. (Rhinoscymnus) rostratus from the eastern North Atlantic and Mediterranean Sea (senior synonym of S. bauchotae) and S. (R.) longus from the western Pacific Ocean. Somniosus longus has been synonymized with S. rostratus, but differs in having a relatively longer second dorsal fin, a slightly larger eye, more lower tooth rows, and slightly higher spiral valve counts. Both Somniosus (Somniosus) antarcticus and S. (Rhinoscymnus) longus from the Pacific Ocean were redescribed. A key to the species and the geographical distribution of all species are provided.  相似文献   

8.
Zusammenfassung Untersuchungen über den Zusammenhang zwischen Legefolge der Eier und Schlüpffolge der Jungen von Tannen- und Blaumeisen erbrachten für die beobachteten Bruten starke Korrelationen für alle Eier eines Geleges. Die biologische Bedeutung des asynchronen Schlüpfens von Meisen ist noch nicht eindeutig geklärt, weitere Studien erscheinen angebracht.
Laying sequence and hatching asynchrony in Coal and Blue Tit (Parus ater,P. caeruleus)
Summary During a long-term study at the Alpenzoo Innsbruck/Tyrol on behaviour and ecology of tits (Parus) selected broods of Coal and Blue Tit were thoroughly checked during the hatching period in 1988 and 1989. The exact sequence of hatching could be determined by two nest controls per hour. Highly significant correlations between sequence of laying and hatching could be found within the whole clutch. The consequences of this laying-dependent hatching asynchrony are not yet fully understood, although as much as eight hypothesis try to explain its biological significance. Further investigations, both long-term and experimental studies, will be necessary to understand adaptive strategies in tits.
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9.
Summary The possible allelic relationship between dasF (dnaA suppressor) and sdrA/rnh (stable DNA replication/RNase H) mutations was examined. dasF mutations could not only suppress various dnaA(ts) mutations, but also the insertional inactivation of the dnaA gene or deletion of the oriC sequence, as could sdrA mutations. dasF mutants were found to exhibit the stable DNA replication phenotype, and the sensitivity to rich media, of sdrA mutants. The dasF and sdrA mutations were mapped very closely between metD and proA on the E. coli genetic map. The mutations were recessive to the wild-type allele for all the above phenotypes. It was concluded that dasF is allelic to sdrA/mh.  相似文献   

10.
Zusammenfassung Ziel der Studie war es, die Elementabfolge sowie die Strophenabfolge des Gesanges von Sprosser und Blaukehlchen vergleichend zu untersuchen. Zur sonagraphischen Analyse wurden die Gesänge im Freiland aufgezeichnet. Der Abfolge (Syntax) der Strophenelemente lag bei beiden Arten ein hierarchisch organisiertes Verzweigungsschema zu Grunde. Bei beiden Arten konnten die Strophen anhand definierter Strukturparameter klar in drei Abschnitte gegliedert werden. Die Gesänge der Sprosser wurden von Serien aus Strophen gebildet, die jeweils in ihren beiden Anfangselementtypen übereinstimmten (gleiche Strophenklasse). Die Abfolge von Strophen verschiedenen Typs war durch bevorzugte Übergänge und ein gruppiertes Auftreten bestimmter Strophentypen charakterisiert. Beim Blaukehlchen traten Strophen, die in allen Abschnitten strukturell gleich waren, seltener im Gesang wieder auf. Die Blaukehlchen wechselten häufiger die Strophenklasse, wodurch es nur seltener zu einer Serienbildung von gleichklassigen Strophen kam. Die auffälligen Gemeinsamkeiten in der Gesangsorganisation zwischen Sprosser und Nachtigall sowie Blaukehlchen und Gartenrotschwanz liefern Hinweise auf Zusammenhänge zwischen der syntaktischen Organisation von Strophen und der Organisation der Strophenabfolge.
Comparison of the song structure and song succession in the Thrush Nightingale (Luscinia luscinia) and the Blue Throat (Luscinia svecica)
Summary Songs of three Thrush Nightingales and three Blue Throats were recorded in the field and analyzed by visual inspection of frequency spectrograms. An analysis of the succession of elements within a song as well as the succession of songs in a song bout revealed the following results in both species: a) the succession of elements within songs was organized as a hierarchical branching structure, b) three structurally different sections could be found in all songs, c) songs were initialized by specific element types. A termination of songs by specific element types was only found in the thrush nightingale.Songs ot the Thrush Nightingale were organized as series of songs which corresponded in their first two element types (same song class). These series consisted of different song types, which succeeded with a high constancy. Different song types were sung in close sequential association and recurred preferably after intervals of 8–10 songs.In song bouts of the Blue Throat however songs which corresponded in all sections were rarely found. Those songs corresponding in the first two element types were often repeated immediately, but in comparison to the Thrush Nightingale series of these songs were rare.Besides many similarities in the song organization in both species the song of the Thrush Nightingale was more similar to the closely related Nightingale (Luscinia megarhynchos) — with regard to the syntactical organization of song and the organization of consecutive songs. The song organization of the Blue Throat showed more similarities to the European Redstart (Phoenicurus phoenicurus).These results indicate a relation between the syntactical organization of song and the sequential organisation of consecutive songs.
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11.
Neoechinorhynchus (Neoechinorhynchus) chimalapasensis n. sp. (Eoacanthocephala: Neoechinorhynchidae) is described from the intestine of Awaous banana (Valenciennes) (Pisces: Gobiidae) collected in the Río Negro, a tributary in the upper Río Coatzacoalcos basin, Santa María Chimalapa, Oaxaca State, Mexico. It is the third species of Neoechinorhynchus Stiles & Hassall, 1905 described from Mexican freshwater fishes, although 36 other species are known from freshwater fishes in the Americas. Like four other species of Neoechinorhynchus from freshwater fishes in North America and Mexico, N. (N.) limi Muzzall & Buckner, 1982, (N.) rutili (Müller, 1780) Stiles & Hassall, 1905, N. (N.) salmonis Ching, 1984 and N. (N.) roseus Salgado-Maldonado, 1978, males and females of the new species are less than 20 mm in length, lack conspicuous sexual dimorphism in size, have a small proboscis of about 0.1 mm in length with the largest hooks being the anteriormost, about 30–90 μm in length and of equal size, and have subequal lemnisci, larger than the proboscis receptacle but still relatively short and, in males, generally restricted to a position considerably anterior to the testes. The new species is closest to N. (N.) roseus, but it is distinguished from it by having: (1) a slightly larger cylindrical proboscis with almost parallel sides versus a globular proboscis with a rounded tip which is shorter and somewhat wider in N. (N.) roseus; (2) smaller but robust anterior proboscis hooks that do not reach the equatorial level or extend beyond the hooks of the middle circle as in N. (N.) roseus; and (3) the female gonopore situated ventrally subterminal, as opposed to being a significant distance anteriorly to the posterior extremity in N. (N.) roseus.  相似文献   

12.
13.
To understand the biogeography of truffle-like fungi, DNA sequences were analysed from representative taxa of Hysterangiales. Multigene phylogenies and the results of ancestral area reconstructions are consistent with the hypothesis of an Australian, or eastern Gondwanan, origin of Hysterangiales with subsequent range expansions to the Northern Hemisphere. However, neither Northern Hemisphere nor Southern Hemisphere taxa formed a monophyletic group, which is in conflict with a strictly vicariant scenario. Therefore, the occurrence and importance of long-distance dispersal could not be rejected. Although a pre-Gondwanan origin of Hysterangiales remains as a possibility, this hypothesis requires that Hysterangiales exist prior to the origin of the currently recognized ectomycorrhizal plants, as well as the arrival of mycophagous animals in Australia. This also requires that a basal paraphyletic assemblage represents parallel evolution of the ectomycorrhizal symbiosis, or that Hysterangiales was mycorrhizal with members of the extinct flora of Gondwana. Regardless, models for both ancient and more recent origins of Hysterangiales are consistent with truffle-like fungi being capable of transoceanic dispersal.  相似文献   

14.
Specimens of Thecaphora saponariae s. lat. from several caryophyllacean host plants belonging to the genera Cerastium, Dianthus, Petrorhagia, Saponaria, Silene, and Stellaria were studied by means of both LM, SEM, and molecular phylogenetic analyses using ITS and LSU rDNA sequences. The data show that T. saponariae s. lat. is not uniform but represents several taxa. Molecular phylogenetic analyses, correlated with morphology of the sori, spore balls, and spores, permitted the recognition of five species. Two new species, Thecaphora italica and T. cerastii are described, and two new combinations, T. alsinearum and T. melandrii are proposed. The anamorph of Thecaphora saponariae is reported for the first time. A lectotype is designated for Sorosporium silenes-inflatae. Evolutionary aspects are discussed.  相似文献   

15.
Traditionally viewed as an Andean grain crop,Chenopodium quinoa Willd. includes domesticated populations that are not Andean, and Andean populations that are not domesticated. Comparative analysis of leaf morphology and allozyme frequencies have demonstrated that Andean populations, both domesticated(quinua) and free-living(ajara), represent an exceptionally homogeneous unit that is well differentiated from allied domesticates of coastal Chile(quingua) and freeliving populations of the Argentine lowlands(C. hircinum). This pattern of relationships indicates that Andean populations represent a monophyletic crop/weed system that has possibly developed through cyclic differentiation (natural vs. human selection) and introgressive hybridization. Relative levels of variation suggest that this complex originated in the southern Andes, possibly from wild types allied withC. hircinum, with subsequent dispersal north to Colombia and south to the Chilean coast. Coastal populations were apparently isolated from post-dispersal differentiation and homogenization that occurred in the Andes. Other data point toward a center of origin in the northern Andes with secondary centers of genetic diversity subsequently developing in the southern Andes and the plains of Argentina. Comparative linkage of South American taxa, all tetraploid, with North American tetraploids of the subsection will eventually clarify this problem. While the possibility of a direct phyletic connection betweenC. quinoa and the Mexican domesticate(C. berlandieri subsp. nuttalliae,) cannot be excluded, available evidence indicates that the latter represents an autonomous lineage that is associated with the basal tetraploid, C. b. subsp.berlandieri, through var.sinuatum, whereas South American taxa show possible affinities to either var. zschackei or var.berlandieri. An extinct domesticate of eastern North America,C. b. subsp.jonesianum, represents either another instance of independent domestication, possibly from subsp. b. var.zschackei, or a northeastern outlier of subsp.nuttalliae.  相似文献   

16.
Zusammenfassung In einer größeren Brutkolonie des Eleonorenfalken der Ägäis siedeln sich die Männchen relativ nahe am Geburtsrevier an (mittlere Ansiedlungsentfernung 192 ± 153 m); die Weibchen zeigen eine etwas größere Dispersion (Ansiedlungsentfernung 738 ± 1104 m) und wandern zu einem kleinen Prozentsatz auch zu den benachbarten Brutkolonien aus. Durch DNA-Fingerprinting mit Oligonucleotidsonden konnte bei 17 Familien mit insgesamt über 60 Jungvögeln gezeigt werden, daß sog. Extra-Pair-Fertilizations und intraspezifischer Brutparasitismus nicht auftreten, d. h. daß die Altvögel am Nest auch die leiblichen Eltern sind. Als Folge der hohen Philopatrie erwiesen sich 24 % der Brutvögel innerhalb einer Inselpopulation als relativ nah verwandt. Mit der eingesetzten DNA-Fingerprinting-Methode kann jedoch nicht die Populationszugehörigkeit erkannt werden.
Population genetics and paternity analysis of Eleonora's Falcon (Falco eleonorae)
Summary Philopatry was studied in a larger breeding colony ofFalco eleonorae on an Aegean island. Male falcons settle in or very close to the territory in which they were born (mean distance 192 ± 153 m), whereas females disperse to adjacent territories (mean distance 738 ± 1104 m) and even colonies to some degree. DNA fingerprinting of 17 families (with a total of over 60 young) revealed that intraspecific brood parasitism and extra-pair fertilizations do not occur although these falcons breed in close vicinity, sometimes only 5 m apart. This means, that the birds feeding at the nest are also the physical parents. Band-sharing coefficients show that the birds within the same colony show some degree of relatedness, but no clear band patterns were evident between different colonies lying within the same island archipelago.
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17.
天然免疫系统是多细胞生物抵抗各种入侵微生物的第一道防线.Notch途径介导相邻细胞之间的相互作用,调节细胞、组织、器官的分化和发育.为了进一步探索Notch信号途径在果蝇天然免疫中的功能,利用Notch途径下游基因Su(H)和E(spl)的低表达突变体果蝇,通过体外注射病原体分析了生存率、血细胞的噬菌功能和抗菌肽的表达量以及突变体的血细胞数量.结果表明,革兰氏阴性细菌和真菌感染后果蝇E(spl)突变体的生存率、噬菌能力及抗菌肽的表达量明显降低,而且幼虫期血细胞出现异常增殖;Su(H)突变体只对真菌表现出敏感性,抗菌肽的表达量降低,但是对真菌的噬菌能力正常.此结果表明,Notch途径不仅影响个体的生长发育,而且在果蝇天然免疫中也起重要的调节作用.  相似文献   

18.
Zusammenfassung Ein über zwei Monate lang in Seewiesen gekäfigter Spechtfink(Cactospiza pallida) benutzte Stäbchen und Kaktusstacheln zum Ertasten, Herausjagen, Aufspießen und Heraushebeln von Beutetieren aus Bohrgängen und Rissen. Auch hebelte er damit Rinde von morschen Ästen. Sein Werkzeug stutzte er häufig auf passende Länge zurecht. Bei der Nahrungssuche behorchte er das Holz nach aufgestörten Insekten. Im Spielverhalten versteckte er Beutetiere in Fugen und holte sie sodann mit seinem Werkzeug wieder heraus; das wiederholte er mitunter viele Male.Beitrag Nr. 2 der Charles Darwin Foundation, Bruxelles.  相似文献   

19.
Results of molecular studies regarding the phylogenetic placement of the order Ostropales and related taxa within Lecanoromycetes were thus far inconclusive. Some analyses placed the order as sister to the rest of Lecanoromycetes, while others inferred a position nested within Lecanoromycetes. We assembled a data set of 101 species including sequences from nuLSU rDNA, mtSSU rDNA, and the nuclear protein-coding RPB1 for each species to examine the cause of incongruencies in previously published phylogenies. MP, minimum evolution, and Bayesian analyses were performed using the combined three-region data set and the single-gene data sets. The position of Ostropales nested in Lecanoromycetes is confirmed in all single-gene and concatenated analyses, and a placement as sister to the rest of Lecanoromycetes is significantly rejected using two independent methods of alternative topology testing. Acarosporales and related taxa (Acarosporaceae group) are basal in Lecanoromycetes. However, if the these basal taxa are excluded from the analyses, Ostropales appear to be sister to the rest of Lecanoromycetes, suggesting different ingroup rooting as the cause for deviating topologies in previously published phylogenies.  相似文献   

20.
Zusammenfassung Während zweier Reisen nach Ostafrika wurden freilebende Populationen zweier Paradieswitwenarten(Steganura paradisaea undSt. obtusa) und der Strohwitwe(Tetraenura fischeri) an drei Stellen in Tanzania (Nord-Paré-Berge, Mikumi National Park, Iringa) beobachtet. Alle drei Arten besiedeln das jeweilige Verbreitungsgebiet ihrer Wirtsvögel in größeren oder kleineren Populationen von kolonieartigem Charakter. Diese Kolonien können weit zerstreut liegen. Weite Gebiete, in denen die zugehörigen Wirtsvögel häufig sind, wurden von den Witwen nicht besiedelt.Die Männchen vonSteganura paradisaea verteidigen tagsüber große Reviere, aus denen jeder männliche Artgenosse vertrieben wird. Zum Imponierflug steigt das Männchen mit gleichmäßig schnellen Flügelschlägen 20–100 m in die Luft und streicht dann geradlinig, in stark verlangsamtem Flug weite Strecken zurücklegend, über dem Revier dahin. Überfliegt ein Rivale das Revier, so steigt das Männchen auf, setzt sich unter ihn und begleitet ihn bis zur Reviergrenze.Während der Brutzeit des Jahres 1966 waren in dem Wohngebiet einerSteganura-para-disaea-Population von 15 Nestern des Wirtsvogels(Pytilia melba) 13 mit Eiern oder Jungvögeln jener Art belegt (86,7 %). Im gleichen Gebiet waren 1969 von 36 Nestern des Wirtes 34 parasitiert (94,5 %). Kurz vor Sonnenuntergang versammeln sich Männchen und Weibchen einer Population zur abendlichen Schwarmstunde. Die Vögel fliegen im Schwarmverband und gehen gemeinsam auf Nahrungssuche. Die Aggressivität der tagsüber streng territorialen Männchen ist während der Schwarmstunde stark herabgesetzt.Im Gebiet der nördlichen Paré-Berge leben zwei Formen des Buntastrild(kirki undpercivali) nebeneinander. Die dortige Paradieswitwenpopulation parasitiert jedoch nur eine dieser beiden(percivali). Die sich aus diesem Befund ergebenden Fragen werden diskutiert.Die Jungvögel vonSteganura paradisaea schlüpfen im allgemeinen früher und sind beim Schlupf größer als die Jungvögel des Wirtsvogels im gleichen Nest. Sie betteln ausdauernder und hartnäckiger und wachsen schneller heran als jene. Trotzdem konnte keine Benachteiligung der eigenen Jungen durch die brutpflegenden Buntastrilde festgestellt werden. Die jungen Paradieswitwen verlassen am 16. Lebenstage das Nest.In Gebieten, in denenSteganura paradisaea undSteganura obtusa nebeneinander leben, können sich die Reviere der Männchen beider Arten überschneiden.Steganura obtusa hat keinen Imponierflug; ein Rivalenbegleitflug konnte wegen der geringen Individuenzahl der beobachteten Population nicht festgestellt werden. Ein Männchen balzte eine Taube(Streptopelia spec.) an und versuchte mit ihr zu kopulieren.In der stationären Balz der beiden Paradieswitwenarten finden sich Elemente aus dem Funktionskreis der Jungenpflege. Das Männchen vonSteganura paradisaea kopiert, stark ritualisiert, einen bettelnden Jungvogel. Das Männchen vonSt. obtusa demonstriert dem Weibchen einen aktiven Fütterungsakt. Die stammesgeschichtliche Herkunft der Elemente und ihre Signalwirkung werden diskutiert.Verbreitung, Populationsdichte, Revierverhalten und Balz der Strohwitwe(Tetraenura fischeri) werden beschrieben. Während der Brutzeit des Jahres 1969 waren innerhalb einer Population des Wirtsvogels(Uraeginthus ianthinogaster) 11 von 15 Nestern durch die Strohwitwe parasitiert (73,3 %).Die junge Strohwitwe verläßt am 16. Lebenstage das Wirtsvogelnest.
Summary During two expeditions to East Africa, free-living populations of two Paradise Widow Birds(Steganura paradisaea andSt. obtusa) and of the Straw Tailed Widow Bird(Tetraenura fischeri) were investigated in three parts of Tanzania (North Paré Mountains, Mikumi National Park and Iringa). All three species occur in the respective areas of distribution of their hosts in larger or smaller populations of colony-like character. These colonies can be widely separated from each other. Large areas where the joint host species is frequent are not colonised by the widow birds.The males ofSteganura paradisaea defend large territories during the daytime from which every male of the same species is driven away. As a display flight, the male flies with regular fast wingbeats 20 to 100 m. high in the air and then makes straight sweeps over the territory in very slow flight, in this way covering large distances. Should a rival enter the territory, the male rises into the air, takes up a position under the bird and accompanies it to the edge of the territory.During the 1966 breeding season, in an area occupied by a population ofSteganura paradisaea, out of 15 nests of the host species examined, 13 were found to contain eggs or young of the parasite (86,7 %). In the same area studied in 1969, 34 out of 36 host nests were parasitised (94,5 %).Shortly before sunset, the males and females of a population group together in an evening assembly. The birds fly in flocks and forage as a group. The aggression shown during the day by the strongly territorial males is much reduced during this period of congregation.Two forms of the Melba Finch(kirki andpercivali) were found to occur sympatrically in the northern Paré-Mountains. The Paradise Widow Bird population there parasitises, however, only one of these two forms(percivali). Questions arising from this finding are discussed.The young ofSteganura paradisaea hatch, in general, earlier and are, on hatching, larger than the young of the host in the same nest. They beg longer and more obstinately and grow faster than the former. Nevertheless, the brooding Melba Finches do not neglect their own young. The young Paradise Widow birds leave the nest on the 16th day of life.In areas whereSteganura paradisaea andSt. obtusa live sympatrically, the territories of the males of each species may overlap.Steganura obtusa has no display flight; whether a rival-accompanying flight is present in this species, could not be definitely determined owing to the small number of individuals in the population studied. One male was seen courting a dove (Streptopelia spec.) and attempting to copulate with it.In the stationary courtship display of the two Paradise Widow Birds, elements from the functional system of young rearing are found. The male ofSteganura paradisaea copies, in strongly ritualised form, a begging nestling. The male ofSt. obtusa demonstrates an active feeding act to the female. The phylogenetical origin of these elements and their signal value are discussed.Territoriality, distribution, population density and courtship behaviour in the Straw Tailed Widow Bird(Tetraenura fischeri) are described. During the breeding period of 1969, in a population of the host(Uraeginthus ianthinogaster) 11 out of 15 nests were found to be parasitised by the Straw Tailed Widow Bird (73,3 %).The young Straw Tailed Widow Birds leave the host's nest on the 16th day after hatching.


mit Aufnahmen des Verfassers und Zeichnungen von H. Kacher

Herrn Prof. Dr. E. Stresemann zum 80. Geburtstag gewidmet  相似文献   

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