Northern Part Of Australia Research Articles

Molecular Genetic (RAPD) Analysis of Breeding Magpie Geese

-Magpie Geese (Anseranus semipalmata) typically form nesting trios consisting of two females and one male, an uncommon breeding arrangement for waterfowl. To study aspects of their reproductive biology, 20 reproductively active adults representing seven reproductive groupings (broods) were scored for 106 polymorphic primer-specific RAPD bands. Genetic distances between all possible adult pairs were calculated, and these values were analyzed using the Mantel test. In the pairwise comparison of genetic distances, those between males were significantly less than those for other adult combinations (P < 0.05). Using the same analytical approach, we found that females that shared a nest were more like one another than were females that did not share a nest (P < 0.05). We suggest that a plausible hypothesis to account for the relative genetic homogeneity of the male population is that males seeking to enter the breeding population do so at their natal site. The females they recruit are more closely related to one another than are females in general. Received 5 April 1995, accepted 29 June 1995. LARGE NUMBERS of Magpie Geese (Anseranus semipalmata) congregate at seasonal wetlands in tropical northern Australia. The bird's unique morphology (including partially webbed, heavily clawed feet with an opposable fourth toe) led to its taxonomic placement in its own family. This uniqueness also is evident at the molecular level, and recent taxonomies derived from mitochondrial DNA sequences support the view that this species should be assigned to a family of its own (Sraml et al. 1996). Although abundant in parts of northern Australia, the current distribution of the Magpie Goose is only a remnant of its former range, which has been severely restricted over the past 200 years by the introduction of European-style agricultural practices. Situations that threaten this species could arise again as the result of conflicts between the bird's habitat requirements and changing human activities. Proposed changes associated with tropical agriculture could threaten the conservation status of these birds (Whitehead 1991). In attempting to sustain adequate numbers of a species, it is important to understand the species' reproductive biology. Unlike most water4E-mail: horn@science.canberra.edu.au fowl, Magpie Geese commonly form breeding trios consisting of two females and one male (Frith and Davies 1961). In situations where females share a nest, all three attendants typically have a direct reproductive (genetic) interest in the clutch, and they are involved in many aspects of care and defense of the eggs and young. Chicks remain with their parents for their first year of life, possibly learning about seasonal resource distribution (Whitehead and Tschirner 1990). The stability of these polygynous groups from year to year distinguishes Magpie Geese from other communal breeders (Brown 1987). When joined in a reproductive trio, individual females seem to decrease their potential reproductive output as measured by numbers of eggs laid. Egg counts (x = 8.6) in nests with only one female and one male are not much smaller than those (x = 9.4) from nests with two females and one male (Frith and Davies 1961). In addition, behavioral observations of trios suggest that males mate with both females and that both females contribute eggs approximately equally to these joint nests. Assignments of young to specific females have been done using restriction-fragment-length-polymorphism (RFLP) analysis of DNA. In making those assignments, conspecific nest parasitism was

Are Thick Volcanic Piles Concealed In North Australian Proterozoic Basins?

Long wavelength magnetic anomalies of moderate amplitude common across large parts of northern Australia are usually assigned to deep sources beneath relatively undisturbed mid Proterozoic or Phanerozoic cover rocks. These can be shown, in the McArthur Basin at least, to be largely due to thick volcanic sequences that either do not outcrop or only outcrop in thinned, onlapped variants near the basin margins. This alternative interpretation of the basin indicates that it might have a scale and formation content comparable with that of the adjacent western Mt Isa sequence and theories about basin formation, mineralising processes and fluid circulation could be reviewed.

Fatal melioidosis in a tourist returning from Thailand

Severe infections with Pseudomonas pseudomallei, the causative agent of melioidosis, is a common cause of community acquired septicaemia in South East Asia and parts of Northern Australia, but infection in travellers returning to the United Kingdom is extremely rare. We describe the case of a tourist who acquired melioidosis in Thailand. Despite intensive intravenous therapy with antibiotics to which the organism was sensitive, the patient's infection proved fatal. Ps. pseudomallei was isolated from blood cultures at a late stage in his illness by use of a commercial blood culture system that included an antibiotic removal device (Bac/TAlert, Organon-Technica).

Distinguishing middens and cheniers: a case study from the southern Kimberley, W.A.

A common phenomenon in northern Australia is the geographically overlapping occurrence of Aboriginal shell mounds or middens, and cheniers. Cheniers are tropical coastal landforms comprising shell or shelly‐sand ridges, developed on wetlands which are referred to as chenier plains. Chenier plains are widely distributed along the low wave energy coastline of northern Australia. The record of prehistoric human occupation of chenier plains in Australia, although incomplete, is better than records from elsewhere in the tropical world. The association of cheniers with shell middens has been described from several localities in northern Australia. Discriminating between the different types of shell deposit is difficult and misunderstandings have occurred. These have resulted in Aboriginal middens mis‐identified as cheniers having been mined for shell grit, and natural shell deposits having been assigned cultural origins.Recent surveys of a section of the Kimberley coastline at Roebuck Bay south of Broome identified a series of shell mounds between 2 and 5km from the coastline, but their status was equivocal. Field investigation, sampling of a range of shell deposits, and excavation indicated three types of deposit were present: chenier mounds, shell middens and middens overlying cheniers. Initial interpretations of the landscape history and discussion of the problem of separating middens from cheniers are presented. The area provides an interesting comparative study for similar sites in prograding landscapes in other parts of northern Australia, such as the Alligator Rivers area, where chenier and midden deposits occur in association.

Chemical composition and acidity of rainfall in the Alligator Rivers Region, Northern Territory, Australia

Rainfall in the Alligator Rivers Region, Northern Territory, is essentially restricted to the period October to April. Rainwater samples from eight sites show that pH is consistently between 4.0 and 5.0, and confirms previous observations of the widespread occurrence of acidic rainwater across the northern parts of Australia. Measurements of anions (sulfate, nitrate, chloride, phosphate) and weak organic acids (formate and acetate) in rainfall, together with pH and conductivity, have shown the presence of local concentrations of ions and the presence of free acidity in excess of that attributed to dissolved carbon dioxide. Much of the acidity was associated with the presence of weak acids; for example, for all Magela samples 47% was weak acids compared with 25.5, 13 and 8% for hydrochloric, sulfuric and nitric acids, respectively. Acidity due to sulfate was therefore low, but sulfate in excess of that derived from sea-salt was of large magnitude; for example, 83% of sulfate for all Magela samples was excess. Possible sources of acidity are natural (burning of vegetation, soil dust, lightning, biogenic emissions from soils and oceans and volcanoes), and anthropogenic (sulfuric acid plant and electricity generating stations and minor emissions from calciners and sulfuric acid aerosols in open vats locally at Jabiru and nearby Nabarlek). The impact of sulfur emissions from the Ranger uranium mine/mill complex (sulfuric acid plant and electricity generating station) on rainwater acidity in the surrounding Jabiru area was examined, but the fate of the sulfur dioxide emissions was not known. Difficulties in establishing the significance of contributions from anthropogenic sources against this background of natural acidity are attributed to a lack of information on the proportions of chloride, sulfate and nitrate from these sources.

Edge-ground axes in Pleistocene Greater Australia - more evidence from S.E. Cape York Peninsula: a reply to Sutton

The Pleistocene antiquity of edge-ground artefacts in various parts of Northern Australia and New Guinea, including the Kimberley, western Arnhem Land and S.E. Cape York Peninsula, is no longer controversial (e.g. Jones and Johnson 1985; Schrire 1982; Rosenfeld et al. 1981). Even so, Sutton (1990:95 - this volume QAR) had rightly questioned the sufficiency of evidence presented by Morwood and Tresize (1990) in support of a minimum date of 32,000 b.p. for edge-grinding at Sandy Creek 1 in S.E. Cape York Peninsula. I welcome this opportunity to rectify this situation.Â

Morning Glory Wave Clouds in Oklahoma: A Case Study

Abstract Early in the morning on 9 June 1982 a system of traveling wave cloud lines passed over 0klahoma, and in particular, over the relatively dense mesonetwork of surface stations, including the instrumented 444 m KTVY television tower, operated by the U.S. National Severe Storms Laboratory. An analysis of the network and other data presented herein shows that, in structure, the associated disturbance was an internal undular bore propagating on a low-level stable layer, similar to “morning glory”-type disturbances, which are common at certain times of the year in parts of northern Australia. Moreover, the speed of propagation of the component bore-waves is in broad agreement with theoretical calculations. There is evidence that the disturbance emanated late the previous evening from an area of rapidly growing intense thunderstorms located more than 400 km north-northwest of the surface mesonetwork. Possible mechanisms for generation are discussed, but the data pertaining to genesis are insufficient to ...

Botanical contributions of the Northern Australia regional survey. I. Studies on Northern Australian species of Eucalyptus

This is the first botanical contribution from the C.S.I.R.O. Northern Australia Regional Survey. Revised accounts of 50 species with discussions on taxonomy, distribution, and typification of names are the result of a partial revision of the genus Eucalyptus as represented in the northern part of Australia; keys to two groups particularly studied are given. All the 42 species known from the northern part of the Northern Territory are treated, with three keys to their identification; the first of these is based on characters observable in the field, the second on hand specimens with buds and flowers, and the third on hand specimens with fruits only. New criteria for the discrimination of species have been used, and some examples of their application are shown graphically; these include the number of lateral veins in the leaf, the ratio of its length to its breadth, and (to some extent) the exact distance of the intramarginal vein from the margin and the shape of the free part of the calyx-tube of the flower. The juvenile stages, flowers, fruits, and seeds are described for the first time for some species. Types of all names, with the herbaria in which they are to be found, are cited, with reference to published figures, some of which appear for the first time in this paper. Several lectotypes are designated, and the guiding principles adopted for their selection are described. Citations of specimens are restricted to those collected in 1946-9 on the Northern Australia Regional Survey, to types, new records, and some critical collections. Distribution maps of 51 species are based on all specimens examined. Plates from photographs illustrate the characteristic habit of some species, the deciduous nature of some, a few characteristic barks, various type specimens and some other specimens cited in taxonomic discussions. The status of about 160 names was investigated. Among others, E. clavigera A. Cunn. ex Schau., E. polycarpa F. Muell., E. terminalis F. Muell., E. foelscheana F. Muell., and E. racernosa Cav. are shown to have been originally applied to species different from those currently passing under these names. Many names are treated as synonyms on taxonomic grounds, 24 of them for the first time. All nomenclatural changes are summarized in two tables. One new species, E. porrecta S. T. Blake, and one new combination, E. gilbertensis (Maiden &amp; Blakely) S. T. Blake, are proposed. The following species are new records for the areas mentioned: E. Izerbertiana and E. cliftoniana (Northern Territory) ; E. aspera and E. ferruginea (Queensland) ; E. bigalerita and E. patellaris (Western Australia) ; and E. dichromophloia (South Australia). In an appendix, the graphical methods and distribution maps are discussed and some remarks made on the phylogeny and history of distribution of the genus.

Glare and its Prevention a Study of the Problems Involved

This paper may conveniently conclude with a brief review of the conclusions arrived at and the suggestions of interest to the Optometrist. (1) Indoor glare is a matter of faulty lighting installations, faulty architecture and incorrect placing of furniture. Where it is impossible to remedy these conditions the use of an eye shade is helpful. (2) Outdoor glare at night is a matter of incorrect street lighting and car headlights. The former is beyond the sphere of Optometrists, but in the latter case we may assist with such aids as Polaroid or Gradutint spectacles if absolutely necessary. (3) outdoor glare during daylight is mostly due, in healthy cases, to an uncorrected error of refraction, the correction of which with white lenses will ease the glare. Where an absorption lens is required it should be of the lightest tint, which will be effective, and should only be worn for the purpose for which it was prescribed. For general purposes and at the seaside, Smoke, Softlite, Crookes' and Fieuzal are recommended, as they do not alter colour values greatly. On snowfields Crookes' and Fieuzal give greater protection from the ultraviolet. In the northern parts of Australia (tropical and sub-tropical) a heat-absorbing lens such as Infrex should be used. Language: en

XLII.—Note on Petasida ephippigera, a Grasshopper found in the interior of the northern part of Australia by Mr. Dring and Dr. Leichhardt

XLII.—<i>Note on</i> Petasida ephippigera, <i>a Grasshopper found in the interior of the northern part of Australia by</i> Mr. Dring <i>and</i> Dr. Leichhardt