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A new species of Amygdalum (Amygdalum anoxicolum n. sp.) isdescribed
living in the soft green muds of the oxygen minimumzone off the Oman
margin in the northern Arabian Sea. It isdistinguished by both its
shell and anatomical characters. Theanatomy is described and
discussed in relation to the environment.The presence of haemoglobin
is viewed as a direct adaptationto the low levels of oxygen found in
its habitat. The observedwide size range of ingested food particles
is discussed in relationto the low oxygen environment. The nest
building habit is assumedto be a key adaptation to living in soft,
high porosity mud.The distribution of the genus is examined in
relation to thedistribution of known zones of hypoxia in the world9s
oceans,but no relationship is evident. Amygdalum species are not
indicatorsof low oxygen environments. (Received 17 August 2000; accepted 14 November 2000) 相似文献
108.
GRAHAM H. PYKE 《Austral ecology》1989,14(4):415-421
Removal of almost all honeyeater nectar sources from a 5.6 ha area during February to July had no apparent effect on honeyeater nesting or total abundance. Behaviour in the experimental area was also generally unaffected except for the extent of nectar-feeding which was significantly reduced for the most commonly observed species. The honeyeaters must have compensated for the nectar removal by flying to nearby productive areas to feed on nectar. Nectar-removal had no significant effect on the species composition of resident honeyeaters but did affect the species composition of all observed honeyeaters. Nectar removal resulted in a decrease in the abundance of the large and dominant Little Wattlebirds (Anthochaera chrysoptera) and an increase in the abundance of the other, smaller species. 相似文献
109.
GRAHAM C. HICKMAN 《Mammal Review》1981,11(2):53-85
Over four hundred reference guides to the mammalian faunas of almost one hundred and fifty countries, dependencies, and well known, geographically isolated areas are listed, including approximately 60% of the total number of countries found in a current atlas.
Although guides to national mammalian faunas have served as useful synopses for large countries and a useful sub-division for large physiographic/ecological areas, most countries either lack a comprehensive reference to the identity, distribution, behaviour, and local literature on mammals, or the existing work has long required revision. Included in this report is a reference list of some important supra-national areas, preceeding a cross-referenced national listing (by current names, with a chronological listing of references within the country).
National mammal guides are not only an invaluable reference source for the professional, but are also an important stimulus to the layman and government at all levels to take an interest in and appreciate the faunal heritage of mammals found within a country. 相似文献
Although guides to national mammalian faunas have served as useful synopses for large countries and a useful sub-division for large physiographic/ecological areas, most countries either lack a comprehensive reference to the identity, distribution, behaviour, and local literature on mammals, or the existing work has long required revision. Included in this report is a reference list of some important supra-national areas, preceeding a cross-referenced national listing (by current names, with a chronological listing of references within the country).
National mammal guides are not only an invaluable reference source for the professional, but are also an important stimulus to the layman and government at all levels to take an interest in and appreciate the faunal heritage of mammals found within a country. 相似文献
110.
Comprehensive clinical assessment and patient management plans have been enhanced by the development of multiaxial classificatory systems. Assessment of risk is an essential clinical task for which the conclusions are not currently reflected in the multiaxial diagnostic schemata. Developments in the understanding of risk and its management make possible consideration of its place in multiaxial systems. The structure and principles of a potentially workable axis, summarizing current knowledge of risk in the domains of suicide, self-neglect and violence to others, are described. Clinicians are more likely to use this axis than the multiple, emerging, risk assessment guidelines. Incorporating risk management would be a practical addition to presently available axes and be very widely clinically applicable. 相似文献