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Erwin Tretzel 《Ethology : formerly Zeitschrift fur Tierpsychologie》1967,24(2):137-161
Bald nach meiner Beschreibung der Schäferpfiffimitationen durch Hauben-lerchen gelangen mir auch die Entdeckung und der analytische Vergleich von Menschenpfiffimitationen durch Amseln. 3 benachbarte Amseln in Garmisch-Partenkirchen trugen gleichartige Imitationen eines Motivs vor, mit dem ein Mensch seit Jahren regelmäßig seiner Katze pfiff. Entferntere Amseln sangen schlechtere Kopien oder ließen z. T. nur Anklänge daran erkennen. Da die Güte der Nachahmungen mit der Entfernung der Amseln vom Vorbild abnahm, wiesen sie mir den Weg zum Wohnsitz desselben: dort variierten die Nachahmungen am wenigsten. Der einfache Pfiff des Vorbildes bestand aus 4 Tönen mit der mittleren Frequenz von 1.19 – 2.07 – 2.19 und 1.74 kHz, entsprechend den Noten d3 (dis3) – c4 – c4 – a3 (vgl. Notenbeispiel auf S. 154), der aber in Tonhöhe und Rhythmus sehr variabel vorgetragen wurde. Die Amseln haben den ganzen Pfiff ura rund eine Quint höher transponiert und verziert: neben einem kurzen Vorschlag vor dem 1. Ton haben sie den 2. Ton mit einem langen und steil aufsteigenden Schleifer versehen, der die Transposition hervorhebt. Die Verzierungen werden als Ausdruck von Spielfreude gedeutet und der Ornamentik unserer Kunstmusik grundsätzlich gleich-gestellt. Während die Tonhöhe des Motivs, beispielsweise seiner beiden hohen Töne, bei 45 Pfiffen des Menschen an 2 aufeinanderfolgenden Tagen inner-halb einer ganzen Oktave schwankte, betrug die Streuung bei 28 Imitationen von 3 Amseln im Zeitraum von 3 Monaten höchstens 1 Ganztonstufe (3.0–3.3 kHz), bei einer einzelnen Amsel (A) nicht über 1 Halbtonschritt. Zweifellos hat nur eine (besonders spottbegabte) Amsel das Vorbild imitiert, und die Nachbarn haben ihre Version gelernt. Auf diese Weise ist die Menschenpfiff-imitation ein Dialektmotiv geworden. Eine Reihe interessanter Parallelen zu den Schäferpfiffimitationen der Haubenlerchen werden aufgezeigt. Vor allem erweisen sich beide Vögel zu akustischer Abstraktion befähigt: sie erfaßten die Motivgestalt des Vorbilds trotz verschiedenartiger Vortragsweise des Menschen richtig, lernten es relativ und wiederholten es mit erstaunlicher Frequenz- und Rhythmuskonstanz. 相似文献
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H. -Dietmar Behnke 《Plant Systematics and Evolution》1977,128(3-4):227-235
The exine-sculpturing of pollen fromGisekia africana (Gisekiaceae),Limeum argute-carinatum (Molluginaceae) andHectorella caespitosa (Hectorellaceae) with supratectate spinulae and an anulopunctate tectum is in accordance with the manyCentrospermae investigated so far with the SEM. Pollen ofRhabdodendron macrophyllum and three species fromGyrostemonaceae do not exhibit these surface details. WhileRhabdodendron with a finely reticulate exine probably fits intoRutaceae, the unique columellaless exine ofGyrostemonaceae has no direct counterpart, neither inCentrospermae nor inCapparales, the two orders to which this family was allied. The genera ofGyrostemonaceae can be distinguished by different arrangements of minute pollen surface details.
Zur Skulptur der Pollen-Exine bei drei Centrospermen (Gisekia, Limeum, Hectorella), bei Gyrostemonaceen und Rhabdodendraceen相似文献
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Von P. Ebinger M. Rhrs J. Pohlenz 《Journal of Zoological Systematics and Evolutionary Research》1989,27(2):142-148
Reductions of brain and eye weight in the wild and domestic turkey (Meleagris gallopavo) Studied is the intraspecific relationship between brain and eye weight to total body weight in native turkes and domestic strains. Brain. The turkeys show a common allometric exponent of a = 0.25. Differences in sex are found only within wild turkeys; gobbler and hen differ by 17.9 %. A reduction in brain weight of 35.2 % between wild male and domestic turkeys and of 23.8 % between wild hen and domestic turkeys are observed. Eyes. Differences in sex within each class independent from body size are not found. But there exist considerable reductions in eye weight from wild to domestic state. In wild turkeys eye weight is by 26.9 % heavier than in domestic strains. Changes in brain size are compared with observations found in other fowls. The two heritable complexes wildness and domesticity are discussed with evolutional, functional and environmental connexions. 相似文献
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Heinrich Drfelt 《Feddes Repertorium》1977,88(4):273-285
Chroogomphus helveticus is an european, dealtomontanous species with a south-hercynian-alpian-carpathian and illyrian-macedonian distribution. It grows in association with various conifers. Picea abies, Pinus cembra, Pinus peuce, Pinus strobus and Abies alba probably are partners of the mycorrhiza. The area is similar to that of Abies alba, Hygrophorus marzuolus and various dealpine plants. Distribution centres are districts, where 5-needled pines (Pinus cembra, Pinus peuce) are to be found naturally. Chroogomphus helveticus is to be found in an altitude from 300 to over 2000 m NN. The species is acidophilous, but not strongly bound to acid soils. A subdivion of the species into subspecific taxa is not possible. The closest relative of Chroogomphus helveticus occurs in Asia and Northern America. An other related european species is only known from England. 相似文献
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Walter Pflumm 《Ethology : formerly Zeitschrift fur Tierpsychologie》1979,50(2):129-135
Several activities of foraging wasps (Paravespula vulgaris) collecting sucrose solution at an artificial food source are described. The concentration of the solution has an influence on the number of preening movements performed per unit time (= rate of preening). The rate of preening as a function of the concentration is explained in a quantitative manner using a diagram which corresponds to the disinhibition hypothesis for displacement activities. 相似文献
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On the cause of the mammalian descent of the testes (Descensus testiculorum) Two explanations have been offered for the descent of the testes in mammals, both of which are frequently cited in the literature. Moore and co-workers argued that the phylogenetic rise of body temperature caused the translocation of the testes. According to Portmann , the descent of the testes was due to the evolution of the scrotum as a signal. However, both the sensibility of the extra-abdominal testes to temperature elevations and the optical effects of the scrotum can be interpreted as a consequence of testicular descent rather than as its cause. The hypothesis presented in this paper suggests a new adaptive explanation for the descent of the testes in mammals and regards its development as an example of evolutionary compromise. Obvious disadvantages such as reduced protection of the extra-abdominal testes, “perforation” of the inguinal abdominal wall, and an increased loss of heat from the body core have to be outbalanced by a strong selective advantage. This advantage is seen in the development of a completely new, fast mode of locomotion - the gallop. The strong flexions and extensions of the vertebral column during gallop should cause intense fluctuations of intra-abdominal pressure. Fluctuations of intra-abdominal pressure severely impede continuous flow of blood in the abdominal veins. Periodically reduced venous drainage resulting in fluctuations of intra-testicular pressure would impair the process of spermiohistogenesis, which is dependent on an absolutely constant pressure within the testis. Thus, it is the displacement of the pressure sensitive testes out of the abdominal cavity that allows for the evolution of a fast mode of locomotion accompanied by strong fluctuations of intraabdominal pressure. In the course of the phylogenetic translocation of the testes increasing specializations of the testicular blood vessels occur. In mammals possessing a scrotum the return flow of venous blood from the extra-abdominal testes to the abdominal cavity is supported by utilizing the energy of the arterial pulse (‘peripheral arterial pump’). A model for the successive stages of the descent of the testes is illustrated in Figures 7–10. The morphological changes related to the phylogenetic descent of the testes, such as the specialization of the testicular blood vessels, the forming of a cremasteric sack in the inguinal region, and the differentiation of the inguinal or perineal integument into a scrotum can all be interpreted as serving one purpose: they aid in maintaining a constant intra-testicular pressure in spite of increasing fluctuations of intra-abdominal pressure and venous blood flow during the evolution of the gallop. Although the blood vessels of the spermatic chord basically serve the same functions, they show markedly different specializations in Marsupials and Eutherians. This indicates that the descent of the testes has occurred independently, at least, in these two groups. The explanation put forward here postulates a causal relationship between the mode of locomotion and the position of the testes. Mammals possessing testes wnich reside permanently within the abdominal cavity (‘Testiconda’) cannot gallop, whereas mammals with the ability to gallop must have (periodical or permanent) extraabdominal testes (‘Testiphaena’). 相似文献
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Brutpflegenden Nannacara anomala-♀♀ wurde die eigene Brut weggenommen und gegen jüngere oder ältere Nannacara-Brut bzw. entsprechende Ersatzobjekte ausgetauscht. Auch ohne vorangegangenes Ablaichen läßt sich Brutpflegeverhalten bei Nannacara-♀♀ durch Brutobjekte auslösen und aufrecht erhalten. Die auftretenden Verhaltensweisen passen zum jeweiligen Entwicklungsstadium der Brut. An der Synchronisation des Brutpflegeverhaltens sind sowohl endogene als auch exogene Faktoren beteiligt. Beim Fächeln zeigte sich eine stärkere Beteiligung endogener Faktoren als beim Kopfzucken. Das spricht dafür, daß zunächst die endogenen, später die exogenen Faktoren überwiegen. Auf das Fächeln wirken endogene Faktoren zunächst fördernd, später im Sinne einer Hemmung ein. 相似文献
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Dr. Nicole Schauerte Dir. Dr. Heike Kück 《Der Zoologische Garten (in deutscher Sprache / in German)》2008,77(3):172-181
The avian influenza A virus (H5N1), which causes the bird flu is latently present in populations of wild birds. The Bremerhaven Zoo is subject to an especially high infection risk owing to its close proximity to the North Sea coast and to resting places of birds. As an alternative to drastically killing all birds in an event of infection, a vaccination campaign was initiated in May 2006 as part of the “Program of the Federal Republic of Germany for the Vaccination of Birds in Zoos against Bird Flu”. The campaign is carried out in cooperation with the responsible authorities. This required formal approval of the authorities was subject to multiple conditions, the fulfilment of which required a large logistic effort. Some issues remained unresolved after the campaign had been completed. It is unclear, for instance, whether or not the applied inoculation is sufficient to immunize infected zoo birds and in which time intervals the vaccination has to be repeated in the future. The legal basis for the handing over of inoculated zoo birds to other institutions is published in the Federal Gazette. 相似文献