Showing papers in "Biological Journal of The Linnean Society in 1970"
TL;DR: The preliminary research in some tropical inland waters of Asia is described and suggestions made concerning Phase II of this project undertaken by the International Biological Programme/ Section PF (Freshwater Productivity) are made.
Abstract: The preliminary research in some tropical inland waters of Asia is described and suggestions made concerning Phase II of this project undertaken by the International Biological Programme/ Section PF (Freshwater Productivity).
Environmental factors were measured in some of the main lakes and rivers and samples taken of the plant and animal life. The stomach contents of over 80 species of fish were examined and the remains of plants and animals present compared with the numbers present in the environment as obtained by the usual hydrobiological netting techniques.
Some of the important problems associated with the biological productivity of these waters is discussed in the light of the results obtained from this preliminary survey.
50 citations
40 citations
TL;DR: Questionnaires in the form of maps were used in the Isles of Scilly with the aim of developing quantitative and objective techniques for studying the effects of visitors on semi-natural areas, indicating that questionnaire-maps and data from the recording devices provide a useful basis for making management proposals.
Abstract: Questionnaires in the form of maps were used in the Isles of Scilly with the aim of developing quantitative and objective techniques for studying the effects of visitors on semi-natural areas. Maps were prepared of intensity of visitor use and distribution of various activities; these were compared with maps of plant communities. In addition photographic, observational and electronic people-counter records were made along transects and compared with vegetation and soil data using partial correlation analysis. The results are discussed and indicate that questionnaire-maps and data from the recording devices provide a useful basis for making management proposals.
39 citations
TL;DR: The collection and analysis of a sample of moths made on an altitude transect on Mt. Kinabalu, Sabah are described and an explanation is presented for the contrast between flora and moth fauna in terms of the relative development of these groups in the two source areas.
Abstract: In this paper the collection and analysis of a sample of moths made on an altitude transect on Mt. Kinabalu, Sabah, are described. The geological and phytogeographical histories of the mountain are reviewed. Single-link cluster analysis is used to pick out faunal elements in the transect. The geographical affinities of the species composing these elements are investigated and discussed.
As with the flora, species in the lowland elements belong largely to centric groups (with centres of speciation coincident with the locality concerned) of the south-east Asian rain forest regions. Increasingly higher elements have an increasing representation of species from eccentric groups. In the flora these eccentric groups are Himalayan and south temperate in roughly equal proportions. In the moth (and bird) fauna they are almost entirely Himalayan centred.
Distribution of montane habitats during the Pleistocene glaciations favoured the colonization of Kinabalu from sources to the south-east. An explanation is presented for the contrast between flora and moth fauna on Kinabalu in terms of the relative development of these groups in the two source areas.
37 citations
TL;DR: Evidence for the dates of publication of the parts of the Transactions of the Linnean Society of London, Series 1-1791–1875, has been collected from the Minute Books of the linnean society, the Journal books of the Royal Society, The Times, Bent's Monthly Literary Advertiser, the Bookseller, the Gardener's Chronicle, and the Athenaeum.
Abstract: Evidence for the dates of publication of the parts of the Transactions of the Linnean Society of London, Series 1,1791–1875, has been collected from the Minute Books of the Linnean Society, the Journal Books of the Royal Society, The Times, Bent's Monthly Literary Advertiser, the Bookseller, the Gardener's Chronicle, and the Athenaeum. Dates have been traced for all parts except five, and two of those may have been issued with other parts that have been dated.
37 citations
TL;DR: A fungus believed to be a member of the Microthyriales is described from the English Wealden, where it occurs on the shoots of an undescribed conifer resembling Frenelopsis Schenk.
Abstract: A fungus believed to be a member of the Microthyriales is described from the English Wealden. It occurs on the shoots of an undescribed conifer resembling Frenelopsis Schenk. From the structure of the thyrothecium and the presence of an epicuticular mycelium, the fungus is classified in the family Micropeltaceae, subfamily Stomiopeltoideae, and is described under the name Stomiopeltites cretacea gen. et sp. nov. It is the earliest fossil record of the Microthyriales.
35 citations
TL;DR: A study of the stance and locomotion of Tyrannosaurus was made for the mounting of the partial skeleton at the British Museum and shows that the posture was much more bird-like than is indicated by previous mounts, and the tail is shorter.
Abstract: A study of the stance and locomotion of Tyrannosaurus was made for the mounting of the partial skeleton at the British Museum (Natural History). This shows that the posture was much more bird-like than is indicated by previous mounts, and also the tail is shorter. During walking the vertebral column was held nearly horizontal with the tail clear of the ground. The fore-limbs acted as struts to stop the body sliding forward as the animal raised its body from the resting position.
30 citations
TL;DR: Infraspecific categories imply infraspecific classification, but there are few species whose internal diversity has been sufficiently studied to permit this in any detail and the suitability of a hierarchical system cannot be assumed.
Abstract: Infraspecific categories imply infraspecific classification, but there are few species whose internal diversity has been sufficiently studied to permit this in any detail. Important variation may be physiological, continuous and unassociated with convenient morphological markers. Conspicuous variation may be biologically trivial and the use of names for these variants gives a misleading view of the species-structure. If we are to classify we must know the relation between the internal and external characters. The suitability of a hierarchical system cannot be assumed. Informal classifications are likely to be of more use than those provided by the Code of Nomenclature. Nevertheless variation undesignated may easily become variation overlooked.
25 citations
TL;DR: In this paper, a combination of light microscope and scanning electron microscope techniques was used to study leaf cuticle macerations of both modern and fossil Taxodiaceae, revealing the structure of the lignified guard cells, which was shown to vary in morphology within the four genera studied.
Abstract: A combination of light microscope and scanning electron microscope techniques has been used to study leaf cuticle macerations of both modern and fossil Taxodiaceae. Under-macerated preparations reveal the structure of the lignified guard cells, which is shown to vary in morphology within the four genera studied. The character is therefore of significance not only to the taxonomist but also to the palaeobotanist, and an example of its use in helping to assign fossil leaves to the genus Cryptomeria is explained.
19 citations
14 citations
TL;DR: Two formal infraspecific categories are necessary, the subspecies and the variety, and two informal, the form and the modification, and the term ‘subspecies’ should be used in a wider sense than is now customary.
Abstract: Comparatively little experimental taxonomy has been done in the Bryophyta or is likely to be done in the near future. While they show a great deal of infraspecific variation this must of necessity be dealt with largely by the methods of classical taxonomy. Too many infraspecific taxa were described in the past, but too few are being described now. Two formal infraspecific categories are necessary, the subspecies and the variety, and two informal, the form and the modification. The term ‘subspecies’ should be used in a wider sense than is now customary. The term ‘form’ should be used more precisely.
TL;DR: The eggs were laid without any external protective structures and lost water readily in unsaturated air; losses of more than 16% of the original fresh weight were usually fatal; development and hatching took place only if the eggs were in contact with water.
Abstract: SUMMARY
This paper presents the results of the first comprehensive study of the biology of a tropical bush-cricket.
The eggs were laid without any external protective structures and lost water readily in unsaturated air; losses of more than 16% of the original fresh weight were usually fatal. Development and hatching took place only if the eggs were in contact with water. The water content increased by about 500% during development. The mean incubation period was 171 and 116 days at constant temperatures of 20oC and 28oC, respectively, but at temperatures fluctuating by±3°C about a mean of 28°C this period was reduced to a mean of 88 days. The eggs failed to develop if exposed to freezing temperatures for more than five days or kept at a constant temperature of 307deg;C or above.
The duration of the nymphal period varied from 83 to 131 days at a temperature range of 22–30°C (mean 26° C). There were four or five nymphal instars in the male and five or six in the female. The linear growth of the hind femur conformed to Dyar's law. There was a conspicuous colour change during development, all the first-instar nymphs being leaf green and the adults predominantly brown.
In nature the species lives exclusively on the forest floor and is markedly nocturnal in habits, hiding underneath litter during the day. The eggs are dormant during the dry season, hatching at the onset of the rains (March/April at Ibadan). The nymphs reach maturity from July onwards and the adults have mostly died off by the end of the rainy season (October).
In the laboratory the species was found to have a temperature preference of 26–32°C, immobilization setting in at 18°C and 42°C, and a humidity preference of 60–80% R.H.; this corresponds with the prevailing conditions in its forest habitat. The nocturnal pattern of activity persisted for several days in continuous darkness, with no marked acceleration. Movement was inhibited for several days by artificial illumination. Reversed illumination reversed the rhythm of activity.
TL;DR: The study of chalk grassland in Northern France has evolved through three main phases as mentioned in this paper : the early 19th century to the First World War, the general flora of Northern France was studied in some detail, but there was little ecological understanding of plant communities.
Abstract: The study of chalk grassland in Northern France has evolved through three main phases. During the period from the early 19th century to the First World War, the general flora of Northern France was studied in some detail, but there was little ecological understanding of plant communities. Some workers, however, did attempt to group chalk grassland species ecologically, and the primitive concepts of plant sociology unconsciously developed. Between the wars, with the growth of plant sociology, chalk grassland studies became more elaborate. Specific associations were now described and the wider aspects of chalk grassland phytogeography considered. The post-war period has seen a great increase in botanical activity in Northern France. There have been many regional chalk grassland studies, all of which, in varying degrees, have employed the techniques of plant sociology. It may at last be possible to synthesise these studies, and to describe the chalk grassland associations of Northern France.
TL;DR: Infraspecific categories are widely used for Lepidoptera, probably because of the attention from collectors that this order has received, but in other groups of insects their use is more restricted.
Abstract: Infraspecific categories are widely used for Lepidoptera, probably because of the attention from collectors that this order has received, but in other groups of insects their use is more restricted. The terms subspecies, race, form, variety, aberration, phase and caste are all employed by entomologists but with no great consistency. This is unfortunate because the phenomena which they are intended to describe are easily categorized; it should be possible to achieve a more standardized usage.
Since genetic isolation is necessary to permit the divergence of a population to a state on which it may be appropriate to bestow an infraspecific label, factors contributing towards a state of isolation in insect populations are discussed.
TL;DR: The development of evolutionary biology has resulted in a better understanding of such concepts as geographical isolation and clinal variation, a different interpretation of such terms as ‘deme’ and ‘race’, and the rejection of such all-embracing terms as‘variety’.
Abstract: The systematics of birds has probably received more attention than that of any other animal group. However, a reassessment of many species, from the point of view of their evolution, would prove valuable both from the point of view of their systematics, and the part played by various populations in speciation.
The development of evolutionary biology has resulted in a better understanding of such concepts as geographical isolation and clinal variation, a different interpretation of such terms as ‘deme’ and ‘race’, and the rejection of such all-embracing terms as ‘variety’. The concept of the ‘ecotype’ plays little part in the systematics of birds, since they are warm-blooded, and independent of direct environmental effects.
TL;DR: The use of the categories ‘variety’ and ‘forma specialis’ is considered, and examples are given of their application in the cereal rusts and in the genera Phoma and Fusarium.
Abstract: The problems facing the mycologist centre on the difficulty of distinguishing between the individual and the population, the degree of host or substratum specialization and the limited range of morphological characters available for use as denning taxa. The use of the categories ‘variety’ and ‘forma specialis’ is considered, and examples are given of their application in the cereal rusts and in the genera Phoma and Fusarium. Micro-evolutionary trends in Auricula auricula are also considered and are used to illustrate how amenable fungi are to studies on speciation.