Spelling suggestions: "subject:"scorpions -- south africa"" "subject:"scorpions -- south affrica""
1 |
Contributions to the biology, anatomy and physiology of Opisthophthalmus Latimanus & other scorpionsAlexander, Anne Joy January 1958 (has links)
[From Introduction] For many years the problem of interrelationships within the Arthropoda and, indeed, the origin of the Phylum itself have been of interest to many zoologists. It was felt, for reasons which will be given later, that one of the studies which might throw some light on this matter is that of the neuromuscular physiology of arachnid appendages. Consequently it was proposed that the work which is reported here should be primarily concerned with this problem. As in so many cases involving live animals, both the experimental subjects and the experimenter gradually managed to change the direction in which work was proceeding and the result is that only a preliminary attack has been made on the original problem, while most of the material submitted here deals either with functional anatomy or with biological-cum-behavioural characteristics of the experimental animal. Thus it was found that to develop experimental preparations for neuro-muscular studies, it was necessary to work out the anatomy of the muscles and nerves of the appendages used; but this it is not enough. For these nerves and muscles are part of a functional complex which operates as a unit and have therefore to be studied in relation to the structures that they move. Considerations at this level, in fact, carried the study to the plane of functional anatomy. Furthermore it was recognised that even the comprehension of a limb as a functional complex cannot be acquired in isolation. All structures have an evolutionary history and in any consideration of functional anatomy this history must be taken into account - even if the consideration requires extension to the problem of the origin of the group immediately under study.
|
2 |
Factors affecting millipede, centipede and scorpion diversity in a savanna environment.Druce, David James. January 2000 (has links)
Millipedes, centipedes and scorpions are an important component of the ground-dwelling
invertebrate fauna, and may have value as bioindicators of ground-dwelling invertebrate
diversity. However, some level of understanding of which factors influence patterns of their
distribution and diversity is necessary prior to any investigation of their use in conservation
planning and as bioindicators. This project was undertaken in the Greater Makalali Conservancy
in the Northern Province. Many methods have been used to sample millipedes, centipedes and
scorpions but the efficiency of these in savanna has not been investigated. One aim was to
determine a method for quantitatively sampling these invertebrates in this environment. Six
sampling methods were tested during the study. Millipedes were found to be efficiently sampled
by active searching 9m2 quadrats and drive transects, centipedes by actively searching 25m2
plots and scorpions by pitfall traps. The other methods tested were wet cloths and cryptozoan
traps. Another aim was to determine spatial and temporal variation in millipede, centipede and
scorpion diversity in the range of habitat types present in the Conservancy. 45 sites within five
habitat types were sampled during three different sampling periods. The highest diversity for
each study group was recorded in the most heterogeneous habitat, with the lowest being
recorded in more homogeneous habitat types. Millipede and centipede diversity was
significantly influenced by habitat type, while sampling period had a significant effect on
millipede and scorpion diversity. Quantifying the effect of various environmental factors on the
diversity of these invertebrates was a further aim. Maps of various Conservancy wide variables
as well as micro-habitat variables were created, including an accurate vegetation map, maps of
soil characteristics, rainfall and temperature. Micro-habitat characteristics were also recorded
within each of the sample sites. Diversity of the three study groups was related to specific
micro-habitat variables. A Geographic Information Systems (GIS) model was created,
predicting millipede, centipede and scorpion diversity in areas of the Conservancy not sampled.
Three undescribed millipede and one centipede species were found and a new distribution
record for a scorpion species was documented. These results emphasise the importance of
invertebrate biodiversity studies in the savanna environment. / Thesis (M.Sc.)-University of Natal, Durban, 2000.
|
Page generated in 0.088 seconds