Laboratory hybridization of Australian Rattus fuscipes and Rattus Lutreolus and its karyotypic confirmation

1979 ◽  
Vol 27 (5) ◽  
pp. 691 ◽  
Author(s):  
BJ Fox ◽  
JD Murray
Keyword(s):  
New South ◽  
New South Wales ◽  
Centric Fusion ◽  
Hybrid Vigour ◽  
Standard Sequence ◽  
Hybrid Offspring ◽  
South Wales ◽  
Length Measurements ◽  
Chromosome Arm ◽  
Rattus Fuscipes

This paper reports successful laboratory hybridization of R. lutreolus lutreolus (2n = 42) and R. fuscipes assimilis (2n = 38). Hybrid offspring grew rapidly (hybrid vigour) to age 24 days. Only one individual survived past 50 days but is fertile. Although intermediate for many characteristics the hybrids resemble R. lutreolus more than R. fuscipes. The hybridization indicates a closer relationship between these species than previously accepted, but there is no evidence of natural hybrids, perhaps due to an ecological separation observed in the field and to behavioural obstacles to mating observed in the laboratory. Hybrid animals (2n = 40) have single fused chromosomes from each of the two pairs of submeta- centrics in the R. fuscipes karyotype. Chromosome arm length measurements and rankings show that one centric fusion (CF1) comprises two longer chromosomes (4 + 8) and the second fusion (CF2) comprises the two shorter chromosomes (10 + 12). These fusions appear to be identical with those we observed in other R. fuscipes populations in New South Wales. The chromosome numbering determined by measurement of unbanded chromosomes in this study appears to differ from the numbering convention currently in use. This emphasizes the need to establish a standard sequence of chromosomes for Australian Rattus.

Effects of logging and fire on small mammals in Mumbulla State Forest, near Bega, New South Wales

1987 ◽  
Vol 14 (2) ◽  
pp. 163 ◽  
Author(s):  
D. Lunney ◽  
B. Cullis ◽  
P. Eby
Keyword(s):  
Small Mammals ◽  
New South ◽  
New South Wales ◽  
Canopy Cover ◽  
Ground Cover ◽  
First Year ◽  
Severe Effect ◽  
South Wales ◽  
Antechinus Stuartii ◽  
Rattus Fuscipes

This study of the effects of logging on small mammals in Mumbulla State Forest on the south coast of New South Wales included the effects of a fire in November 1980 and a drought throughout the study period from June 1980 to June 1983. Rattus fuscipes was sensitive to change: logging had a significant impact on its numbers, response to ground cover, and recapture rate; fire had a more severe effect, and drought retarded the post-fire recovery of the population. The three species of dasyurid marsupials differed markedly in their response to ground cover, canopy cover, logging and fire. Antechinus stuartii was distributed evenly through all habitats and was not affected by logging, but fire had an immediate and adverse effect which was sustained by the intense drought. A. swainsonii markedly preferred the regenerating forest, and was not seen again after the fire, the failure of the population being attributed to its dependence on dense ground cover. Sminthopsis leucopus was found in low numbers, appeared to prefer forest with sparse ground cover, and showed no immediate response to logging or fire; its disappearance by the third year post-fire suggests that regenerating forest is inimical to the survival of this species. Mus musculus showed no response to logging. In the first year following the fire its numbers were still very low, but in the next year there was a short-lived plague which coincided with the only respite in the 3-year drought and, importantly, occurred in the intensely burnt parts of the forest. The options for managing this forest for the conservation of small mammals include minimising fire, retaining unlogged forest, extending the time over which alternate coupes are logged and minimising disturbance from heavy machinery.

Temporal activity patterns of the swamp rat (Rattus lutreolus) and other rodents in north-eastern New South Wales, Australia

2012 ◽  
Vol 34 (2) ◽  
pp. 223 ◽  
Author(s):  
Paul D. Meek ◽  
Frances Zewe ◽  
Greg Falzon
Keyword(s):  
New South ◽  
Activity Patterns ◽  
New South Wales ◽  
Camera Trap ◽  
Mammal Species ◽  
South Wales ◽  
North Eastern ◽  
Time Partitioning ◽  
Rattus Fuscipes ◽  
Small Mammal Species

The activity patterns and partitioning of time by four small mammal species, with a focus on the swamp rat (Rattus lutreolus) in north-eastern New South Wales, was investigated using camera trap data from two studies. Analysis was carried out on 1079 camera trap events over 1530 camera trap–nights or 36 720 h of camera trap deployment in the field. The activity patterns of Rattus lutreolus were distinctly diurnal with crepuscular peaks of activity but this differed between sites and when in the presence of competitors. The Hastings River mouse (Pseudomys oralis) and the bush rat (Rattus fuscipes) displayed typical bimodal patterns of nocturnal activity. Antechinus were mostly nocturnal but were occasionally active during the day. These data indicate that where species of Muridae co-occur, diurnal time partitioning by R. lutreolus may reduce competition for food resources. It also confirms the speculation that R. lutreolus displays diurnal behaviour, albeit dependent on the presence of other murids.

Small Mammal Populations in Pine and Native Forests in North-Eastern New South Wales.

1977 ◽  
Vol 4 (3) ◽  
pp. 233 ◽  
Author(s):  
JL Barnett ◽  
RA How ◽  
WF Humphreys
Keyword(s):  
Pinus Taeda ◽  
New South ◽  
New South Wales ◽  
Native Forest ◽  
Vegetation Types ◽  
North East ◽  
South Wales ◽  
North Eastern ◽  
Antechinus Stuartii ◽  
Rattus Fuscipes

Populations of small mammals were examined in a 6 yr Pinus taeda plantation (extended to include similar age P. radiata) and adjacent native rain forest in north-east New South Wales, Australia. Of the 6 species trapped, Rattus fuscipes was the only one with viable populations in both vegetation types. R. lutreolus, R. rattus and Mus musculus were restricted to the plantation; Melomys cervinipes and Antechinus stuartii (except for a few individuals) were confined to the native forest.

The Diet of Foxes, Vulpes Vulpes (L.), In Relation to Abundance of Prey Above the Winter Snowline in New South Wales.

1981 ◽  
Vol 8 (2) ◽  
pp. 349 ◽  
Author(s):  
K Green ◽  
WS Osborne
Keyword(s):  
Vulpes Vulpes ◽  
National Park ◽  
New South ◽  
New South Wales ◽  
Selective Predation ◽  
Seasonal Trends ◽  
High Occurrence ◽  
South Wales ◽  
Rattus Fuscipes ◽  
Staple Diet

In areas above 1500 m altitude in Kosciusko National Park, New South Wales, between December 1978 and February 1980, the diet of foxes showed strong seasonal trends, with a high occurrence of Orthoptera and Lepidoptera in the snow-free months when these were common, and a general absence of invertebrates when snow covered the area. Small native mammals occurred in the diet in all months and were the winter staple diet; the genera preyed upon were Antechinus, Burramys, Mastacomys and Rattus. Mastacomys fuscus, although less common than Rattus fuscipes, was preyed upon as heavily; the implications of this selective predation are discussed. Foxes showed some selective patterns of predation both in the snow-free months and in winter.

Cytogenetics of the viatica group morabine grasshoppers. I. The coastal species

1967 ◽  
Vol 15 (2) ◽  
pp. 263 ◽  
Author(s):  
MJD White ◽  
RE Blackith ◽  
RM Blackith ◽  
J Cheney
Keyword(s):  
Sex Chromosome ◽  
New South ◽  
New South Wales ◽  
Far East ◽  
South Australia ◽  
Centric Fusion ◽  
Flinders Ranges ◽  
South Wales ◽  
Coastal Species ◽  
Usual Process

The viatica group (Acridoidea : Eumastacidae : Morabinae) includes about eight presumptive species of grasshoppers. The group as a whole is distributed from the west coast of the Eyre Peninsula and the Flinders Ranges in South Australia through parts of western New South Wales and the mallee country of north-western Victoria. One species (viatica) extends throughout coastal Victoria as far east as the Bairnsdale area and also occurs in Tasmania. The present paper deals with the cytogenetics of what we call the "coastal" forms. Certain other inland members of the group which occur in the mallee country, in the Flinders Ranges, and in western New South Wales will be dealt with in a later paper. The primitive karyotype of the group has 2nB = 19, there being separate "A" and "B" acrocentric chromosomes, a "CD" metacentric and six pairs of smaller autosomes. The primitive sex chromosome mechanism was of the XO type, but three separate X-autosome fusions have occurred in the phylogeny of the group, giving rise to XY (B) races of originally XO (B) species. In two of these the neo-XY mechanisms have arisen through the usual process of centric fusion between an acrocentric X and an autosome; in the third case, however, the fusion was a tandem one, and the XY bivalent is consequently unique for orthopteroid insects in that it is postreductional, the X and Y segments separating at the second anaphase rather than at the first one. In addition to X-autosome fusions, a centric fusion between two autosomes is present in two taxa of the viatica group. In one of these a local race is homozygous for a translocation between the two largest chromosomes. A number of small pericentric inversions have reached fixation in certain populations, races and species. Hybrids between many of the species and races have been reared in the laboratory. Hybrid progenies consisted of males and females in approximately equal numbers and development of the gonads in both sexes was normal. The meiosis of the hybrids provides evidence as to the course of evolution of the group. It is concluded that the "coastal" species and races have been derived from an ancestral species, "proto-viatica" as a result of a number of chromosomal re-arrangements which have spread out from their points of origin, giving rise to the present-day mosaic pattern of geographic distribution. This type of speciation is discussed in relation to the well-known "allopatric" and "sympatric" models.

Radiotherapy utilization in New South Wales from 1996 to 1998: Comment

2000 ◽  
Vol 44 (4) ◽  
pp. 483-484 ◽  
Author(s):  
JH Kearsley
Keyword(s):  
New South ◽  
New South Wales ◽  
South Wales

Plants of New South Wales

2009 ◽  
Author(s):  
F. Von Mueller
Keyword(s):  
New South ◽  
New South Wales ◽  
South Wales

Notes and Sketches of New South Wales

2009 ◽  
Author(s):  
Louisa Anne Meredith
Keyword(s):  
New South ◽  
New South Wales ◽  
South Wales

The History of New South Wales

2009 ◽  
Author(s):  
Roderick Flanagan
Keyword(s):  
New South ◽  
New South Wales ◽  
South Wales ◽  
History Of
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