共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
3.
4.
Alan Walker 《African Journal of Ecology》1969,7(1):1-5
The stealthy locomotion of the lorises is seen to be directly related to catching prey such as insects and roosting birds. The method of stalking prey contrasts strongly with the quick leaping method of food-catching presented by the galagos. The lorises, by virtue of their food-catching habits, are restricted to true forest, whereas some of the galagos, by the same token, have colonized more open country. This throws some light on the nature of the post-Miocene link between Africa and Asia and is suggested as a reason why the galagos are restricted to Africa whereas the lorises are found in both Africa and Asia. 相似文献
5.
KEITH STEWART THOMSON 《Journal of Zoology》1965,145(2):207-238
An investigation is made of the homology of the nasal apparatus of the Dipnoi, in order to determine whether the posterior naris is homologous with the choana of tetrapods or with the posterior external naris of fishes. The ontogeny of the nasal capsule of Protopterus is described in detail. The nervous and venous systems of tho snout region of Protopterus are also duscrbed. It is found that whereas the pattern of the nervous and vascular systems is very similar in all Dipnoi, the structuro of the nasal capsule in the Lepidosiren-Protopterus stock differs greatly from that of the Neoceratodus stock. the homology of the various components of the depnoan nasal coasule is revised and it is shown that there are no evidences of a direct relationship of the Dipnoi with the tetrapods. It is further concluded that the posterior naris of Dipnoi is homologous with the posterior external naris of fishes. 相似文献
6.
Analysis of published records of the food of flycatchers (Tyrannidae), swallows (Hirundinidae) and vireos (Vireonidae) of North America, and terns (Laridae) of the Pacific Ocean showed that size, rather than taxonomic, differences in food appear to be the most important ones for these birds. Although the distribution of insect sizes in nature approaches a two-parameter log-normal distribution, the distributions of the sizes of food items taken by birds show no significant differences from log-normal. Birds of a given feeding type (e.g. flycatchers) show a strong correlation of average prey size with bird body weight, and a significantly less strong correlation with bill characteristics, indicating that body size is a better predictor of prey size than any single bill character. The slopes and/or intercepts of regressions of food size against body weight are different for birds of different foraging type. Values of overlap in food preference are proportional to the similarity of the two species compared, expressed as the ratio of their weights. Because insect taxa differ in size and because the amount of overlap in taxonomic composition of foods is therefore very roughly proportional to the amount of overlap in size, taxonomic differences in food may merely reflect differences in size preferences. Values for overlap in food are greater than for most cases involving spatial niche parameters, indicating space is more easily divided than food, a conclusion supported by the relative rarity of large flycatchers. 相似文献
7.
8.
W. B. TURRILL 《Biological reviews of the Cambridge Philosophical Society》1938,13(4):342-373
9.
10.
11.
12.
Six varieties of Leishmaniasis are briefly described, namely,visceral leishmaniasis, oriental sore, Chiclero's ulcer, Panamaniancutaneous leishmaniasis, mucocutaneous leishmaniasis, and Uta.The natural foci of these diseases are described, and the evolutionof each infection from its original location in the animal reservoirto total humanisation is followed. In the main, the wild canidaeform the reservoir of the visceral diseases, and rodents ofthe cutaneous form. Many fallacies exist in the interpretation of what constitutesa zoonosis in leishmaniasis, and each situation must be lookedat very carefully to ascertain the precise epidemiology. Thecontrol measures depend entirely upon a correct assessment ofthe position. 相似文献
13.
MORPHOLOGY AND TAXONOMY OF THE OOMYCETES, WITH SPECIAL REFERENCE TO SAPROLEGNIACEAE, LEPTOMITACEAE AND PYTHIACEAE 总被引:1,自引:1,他引:0
M. W. DICK 《The New phytologist》1969,68(3):751-775
14.
15.
《Lichenologist (London, England)》1999,31(5):511-516
Abstract: Four primers for the amplification of mitochondrial DNA of lichen-forming ascomycetes are presented. The primers match the conserved regions U2, U4, and U6, respectively, of mitochondrial small subunit (SSU) ribosomal DNA (rDNA). Polymerase chain reaction using different combinations of the primers produced single amplification products from DNA of eight lichen-forming fungal species but did not amplify DNA of two axenic cultured algal species. The amplification product obtained from Lobaria pulmonaria was sequenced and the 894-bp sequence was compared with the mitochondrial SSU rDNA sequence of Podospora anserina. The two sequences revealed more than 76% identity in the conserved regions U3 to U5 demonstrating that we amplified mitochondrial DNA. The primers matching U2 and U6 yielded amplification products of 800–1000 bp depending on the species examined. The variation observed suggests that mitochondrial SSU rDNA may be useful for phylogenetic analyses of lichen-forming ascomycetes. 相似文献
16.
17.
18.
19.
S. M. HAQ 《Journal of Zoology》1965,144(2):175-201
The development of Euterpina acutifrons is described from observations of individuals reared in the laboratory. The characteristics which enable the various stages to be identified have been listed and the feeding mechanism of the larvae described. Differences from the usual developmental pattern of the Harpacticoida are noted and it is suggested that these are related to the pelagic habit of Euterpina . Dimorphism in the male is described and the course of development of the dimorphs is shown to differ from schemes previously suggested for other copepods. Dimorphism, which is manifested at the moult of the third copepodid, is shown to be independent of temperature. 相似文献
20.