摘要:

Morphological features are similar to most other types of features insofar as their patterns of geographic variation can be caused by both current ecological conditions and historical factors i.e. phylogenesis. Geographic variation in morphology is almost universal and often complex. Morphological and other features show a wide range of patterns of geographic variation i.e. clinal, categorical, and mosaic etc. The extent of pattern congruence between characters is to some extent predicted by both the extent of genetic independence and the cause of the geographic variation. The existing ≪conventional≫ procedure of naming subspecies typically fails to take into account the facts of intraspecific variation and consequently does not elucidate the patterns of geographic variation or their cause. Multivariate character analysis, based on ordination analysis and assisted by mapping techniques, can elucidate the range of patterns of geographic variation and may indicate their congruence, predictivity and cause. A more directly hypothesized intraspecific phylogeny can be obtained from qualitative karyotypic information or numerical phylogenetic analysis of quantitative morphological (and other) data. When the pattern of anagenesis is considered numerical phylogenetic analysis of morphological data indicates the primary or secondary origin of some transition (hybrid) zones. It is evident from the morphological and other studies that intraspecific lineages and their reticulation can be defined and that their ability to reticulate is not necessarily related to rank. Conventional subspecies are found not to relate to multivariate patterns or hypothesized phylogeny. If subspecific nomenclature is to be used then consideration should be given to the nature of the geographic variation, its cause and its rank.

ISSN:0373-4137    

DOI:10.1080/11250008709355549

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Studies using the Nissl method on thick paraffin sections of the preoptic region of the Japanese quail hypothalamus reveal a complex cytoarchitecture with several differentiated nuclei. The most prominent nucleus is the medial preoptic nucleus whose staining and volume appear sexually dimorphic. A higher number of intensely stainable neurons are present in males than in females, probably reflecting different metabolic rates in the two sexes. The volume of the medial preoptic nucleus is also larger (40Z) in males than in females. Present results represent the first description of a sex‐related dimorphism in the hypothalamus of non‐mammalian vertebrates.

ISSN:0373-4137    

DOI:10.1080/11250008709355550

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Morphometric, histological and histochemical investigations were carried out on the labial salivary glands of the one‐humped camel (Camelus dromedarius).Both the supra‐and infralabial glands of the camel are of the branched tubuloalveolar type and are composed of mucoserous acini capped by serous demilunes. They secrete and process neutral mucosubstances, sialomucins, hyaluronic acid and chondroitin sulphate A, B, C containing sulphomucins as well as protein radicals. The histoenzymological tests employed have detected alkaline phosphatase, acid phosphatase, adenosine triphosphatase, succinic dehydrogenase, non‐specific esterases, carbonic anhydrase and amylase, but neither aminopeptidase nor tryp‐sin‐like enzymes.

ISSN:0373-4137    

DOI:10.1080/11250008709355551

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Adaptive radiation which has occurred in marine Tardigrada is discussed on the basis of the wide variety of species. The establishment of a new family, Neostygarctidae, is proposed and the hypothesis that two evolutive lines started from it is advanced. The possible affinities with other phyla are also discussed.

ISSN:0373-4137    

DOI:10.1080/11250008709355552

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

A comparison is made between two Italian populations ofMacrothrix hirsuticornisfrom two basins with different characteristics: a lowland temporary pond and a mountain lake. A survey was carried out on the biological cycle which showed both in the wild and in the laboratory a high ecophysiological diversity. As far as the morphological characteristics are concerned, these populations have an accentuated variability with individuals displaying characteristics fromhirsuticorniss. str.,groenlandicaand intermediate forms. However there is the highest percentage ofgroenlandicaat high altitudes and ofhirsuticorniss. str. in lowland areas.

ISSN:0373-4137    

DOI:10.1080/11250008709355553

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The holomediterranean speciesBacillus rossiusincludes many subspecific taxa, which can be characterized both on the basis of electrophoretic allozyme frequencies and egg chorionic pattern. At present, 8 subspecies have been identified; they are, following a clock‐wise direction from the south‐eastern to the north‐western:B.r. tripolitanusA,B.r. tripolitanusB,B.r. lobipes, B.r. montalentii, B.r. medeae, B.r. catalauniae, B.r. rossius,and B.r.redtenbacheri.Opercular details do not unequivocally specify intraspecific taxa, however these taxa sea can be clearly recognized from the fine chorionic SEM patterns of eggs laid by field collected females.B.r. tripolitanusA andB.r. tripolitanusB show a pattern of single small mamelons, while all the others have a ribbon design, more often with a lace‐net distribution. InB.r. redtenbacherisuch a pattern breaks down to give strings of different size mamelons. It would seem that the lace‐net ribbon pattern, owing to its frequent occurence and geographically wide distribution, is the ancestral one for the species. This also appears to be supported by comparative findings in related species such asB. grandiiand all the easternBacillusspecies. The ootaxonomical observations confirm electrophoretic evidence demonstrating that inB. rossiusparthenogenesis has arisen several times, independently in different areas of the species’ range.

ISSN:0373-4137    

DOI:10.1080/11250008709355554

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Cytological, cytochemical and molecular investigations have shown different trends in DNA evolution among different lineages of reptiles. In chelonians, qualitative and quantitative differences in all the main DNA fractions (highly repetitive, middle repetitive and single‐copy DNAs) have been found. These variations do not seem to be correlated with phylogeny nor with the taxonomic position of the species studied so far; they might result mainly from variations in the amount of non‐functional DNA fractions.

ISSN:0373-4137    

DOI:10.1080/11250008709355555

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

We report that rabbit antibodies against goldfish immunoglobulins (C‐Ig) bind goldfish erythrocytes (C‐RBC) in agglutination and immunofluorescence assays. These reactions can be inhibited by absorption of rabbit antiserum with goldfish spleen leukocytes and either C‐Ig or their large fragments (> 40 kd M.W.) obtained after peptic digestion, but not with small fragments (< 20 kd). Trypsin treatment of C‐RBC enhances the agglutination titre of the rabbit antiserum even after 24 hrs incubation of trypsinized C‐RBC in tissue culture medium. The present data show that C‐RBC have membrane molecules which cross‐react with C‐Ig and therefore could be relevant in furthering our understanding of the biology of the nucleated RBC in lower vertebrates.

ISSN:0373-4137    

DOI:10.1080/11250008709355556

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Sensitivity of burnet mitochondria to cyanide was studied and some detoxifying mechanisms were investigated. Results showed that burnet mitochondria are relatively sensitive to KCN and that the inhibitory effects of cyanide can be completely reversed by pyruvate. Additionally, some glycolytic intermediates were determinedin vivoat differential times from the beginning of the crushing‐induced thanatosis and at subsequent arousal.

ISSN:0373-4137    

DOI:10.1080/11250008709355557

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Forty‐four virgin female albino mice were presented individually on one occasion only, with either a three‐day‐old pup or a foetus removed on the eighteenth day of pregnancy. The stimulus‐objects in question had all been frozen, defrosted and washed, in order to minimize differences between them. The foetuses did have some capacity to elicit parental behaviour but pups were more effective in this respect. Although for the present any interpretation in terms of infantile signals is difficult, these results indicate that adults, even when presented with dead animals, are adapted to respond to a pup more than to a foetus.

ISSN:0373-4137    

DOI:10.1080/11250008709355558

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor