The dynamics of B chromosomes in populations of the Australian plague locust, Chortoicetes terminifera (Walker)

1984 ◽  
Vol 26 (2) ◽  
pp. 194-208 ◽  
Author(s):  
P. C. Gregg ◽  
G. C. Webb ◽  
M. A. Adena
Keyword(s):  
New South ◽  
Female Parent ◽  
B Chromosome ◽  
Average Frequency ◽  
B Chromosomes ◽  
Banding Patterns ◽  
South Wales ◽  
Random Fashion ◽  
Accumulation Mechanism ◽  
Males And Females

The B chromosomes of Chortoicetes terminifera possess an accumulation mechanism. B chromosomes were transmitted at a rate of 0.766 in one B(♂) × zero B(♀) crosses and 0.477 in zero B(♂) one × B(♀) crosses. In crosses where the female had a B chromosome, there were significant differences in transmission rates between pods, but these were not related to differences in G-banding patterns of the B chromosomes involved. In crosses where either the male or female parent had two B chromosomes the B chromosomes did not segregate perfectly, nor did they segregate in a random fashion. The closest resemblance to the behaviour of normal bivalents occurred when the two B chromosomes were of the same, rather than different, G-banding variants, and when they were present in the male rather than the female parent. B chromosomes occurred at eight localities scattered throughout New South Wales. No locality was found where they were not present. The average frequency of B chromosomes was 14.0% for one-B individuals and 0.8% for two-B individuals. There were no significant differences in B-chromosome frequency between males and females. Of the eight localities, only one had a B-chromosome frequency significantly different from any other locality. This relatively uniformity of B-chromosome distribution is interpreted as a consequence of the migratory nature of C. terminifera. A model was constructed to simulate the dynamics of B chromosomes in locust populations. Three main dynamic patterns were recognized, and these were related to differences in the fitness of one-B and two-B individuals. It was concluded that the B chromosome of C. terminifera is probably parasitic, although the simulation model revealed some difficulties which suggest that caution should be applied to the description of any B chromosome as purely parasitic.Key words: B chromosomes, locust, meiotic drive, G-banding, fitness. Chortoicetes terminifera (Walker).

Seasonal Field Energetics of the Rufous Rat-Kangaroo (Aepyprymnus-Rufescens)

1992 ◽  
Vol 40 (3) ◽  
pp. 279 ◽  
Author(s):  
IR Wallis ◽  
B Green
Keyword(s):  
New South ◽  
Water Flux ◽  
Behavioural Ecology ◽  
Free Living ◽  
Doubly Labelled Water ◽  
South Wales ◽  
Poor Understanding ◽  
Males And Females ◽  
The Mean ◽  
The Difference

Water flux and field metabolic rate (FMR) were measured by the doubly labelled water (DLW) method in free-living male and female rufous rat-kangaroos Aepyprymnus rufescens near Drake in northern New South Wales. The mean FMR of 499 kJ kg-1 day-1 was similar in winter and summer even though the difference in mean minimum temperatures between the two seasons was 20-degrees-C. Furthermore, we did not find any differences in FMR between males and females even though several females carried large pouch young or had young-at-foot. A poor understanding of the diet and the behavioural ecology of A. rufescens makes ft difficult to explain the similarities between sexes and seasons.

Revision of the Australian wolf spider genus Anomalosa Roewer, 1960 (Araneae: Lycosidae)

Zootaxa ◽  
2006 ◽  
Vol 1304 (1) ◽  
pp. 1 ◽  
Author(s):  
VOLKER W. FRAMENAU
Keyword(s):  
New South ◽  
South Australia ◽  
Wolf Spider ◽  
Original Description ◽  
Morphological Evidence ◽  
Pitfall Traps ◽  
Systematic Revision ◽  
South Wales ◽  
As Species ◽  
Males And Females

The wolf spider genus Anomalosa Roewer, 1960 is revised with Anomalosa kochi (Simon, 1898) as type species. Anomalosa includes a further Australian species, A. oz sp. nov. Representatives of Anomalosa are small, elongated lycosids with a longitudinal light median band on the dorsal shield of the prosoma and on the opisthosoma, the latter being particularly distinct in males. They are closely related to Venonia Thorell, 1894. Similar to Venonia, males have a bipartite prolateral tegular lobe on the pedipalp, but it is much larger than in Venonia and, in contrast to Venonia, larger than the membranous tegular apophysis. Anomalosa kochi has only been found in Queensland, whereas the distribution of A. oz sp. nov. includes New South Wales, South Australia and Victoria. This allopatric distribution coincides with the McPherson Range as a biogeographical border. Although most males and females of Anomalosa have been caught in pitfall traps or running freely in moderately moist habitats, such as near creeks and dams, there is evidence that representatives of this genus build sheet-webs similar to Venonia. This behaviour is supported by morphological evidence as species of Anomalosa have elongated posterior spinnerets. The original description of A. harishi (Dyal, 1935) from Panjab, India, does not match the diagnosis of Anomalosa. Consequently, I reject the inclusion of A. harishi in Anomalosa and re-transfer it to its original genus Anomalomma Simon, 1890, Anomalomma harishi Dyal, 1935, pending a systematic revision of this genus.

Factors affecting pre-weaning growth and weaning conformation of Angus cattle

1978 ◽  
Vol 29 (2) ◽  
pp. 359
Author(s):  
R Barlow ◽  
EB Dettmann ◽  
LG Williams
Keyword(s):  
Least Squares ◽  
New South ◽  
Average Daily Gain ◽  
Factors Affecting ◽  
Angus Cattle ◽  
South Wales ◽  
Weaning Age ◽  
Males And Females ◽  
Main Effects ◽  
Daily Gain

Weaning weight (ww) and conformation score (cs) records from Angus calves in five New South Wales herds were analysed by least-squares procedures to assess the nature and magnitude of variation. Herd, year, age of dam and sex were considered as main effects. Covariates included in the models were weaning age (WA) for ww and average daily gain (ADG), and both WA and ww for cs. Male calves (steers and bulls) were 16.6 kg heavier at weaning than female calves. Dams that were 5-8 years of age weaned calves that were 30.1 kg, 15.4 kg and 6.7 kg heavier than 2-, 3- and 4-year-old dams respectively. When ww was not included as a covariate in the model, age of dam effects on cs reflected those on ww, and there was little difference in cs between males and females. When adjusted for differences in ww, males had poorer cs than females, and calves from 3-year-old dams, and from dams over 8 years old, had poorer cs than those from dams of all other ages. Partial regressions of ww and ADG on WA, and of cs on ww, varied considerably between herd/year/sex subgroups.

Australian trends in mortality by socioeconomic status using NSW small area data, 1970–89

1995 ◽  
Vol 27 (4) ◽  
pp. 409-419 ◽  
Author(s):  
Susan Quine ◽  
Richard Taylor ◽  
Lillian Hayes
Keyword(s):  
Socioeconomic Status ◽  
Local Government ◽  
Census Data ◽  
New South ◽  
Common Trend ◽  
South Wales ◽  
Males And Females ◽  
Socioeconomic Differentials ◽  
Industrialised Countries ◽  
The Relationship

SummaryThis ecological study examines trends in socioeconomic differentials in mortality in New South Wales, Australia, over a 20-year period (1970–89). The proportion unskilled was used as the indicator of socioeconomic status and its selection justified. Using census data aggregated by Local Government Area, the relationship between mortality and socioeconomic status was examined using quintiles based on the proportion unskilled in the population. Local Government Areas were also sorted into quintiles using mortality rates (0–74 years) to describe change in mortality differentials over time. Socioeconomic differentials were more evident in the relatively homogeneous Local Government Areas within the Sydney Statistical Division than in the remaining NSW Statistical Divisions which are more heterogeneous and predominantly rural. Although there has been an overall decline in mortality for males and females, and for high and low status groups, over this period the relative socioeconomic differentials have not declined. For the most recent period (1985–89) there appears to be some widening of differentials for males. The NSW state trends are generally similar to those reported for Britain and for other industrialised countries, suggesting that this is a common trend and that policies to reduce inequalities have not been effective.

Latitudinal and seasonal effects on growth of the Australian eastern king prawn (Melicertus plebejus)

2012 ◽  
Vol 69 (9) ◽  
pp. 1525-1538 ◽  
Author(s):  
Luke R. Lloyd-Jones ◽  
You-Gan Wang ◽  
Anthony J. Courtney ◽  
Andrew J. Prosser ◽  
Steven S. Montgomery
Keyword(s):  
Growth Rate ◽  
Shape Parameter ◽  
New South ◽  
Seasonal Effects ◽  
Seasonal Effect ◽  
Model Framework ◽  
Mark Recapture ◽  
South Wales ◽  
Males And Females ◽  
Latitudinal Effect

The growth of the Australian eastern king prawn ( Melicertus plebejus ) is understood in greater detail by quantifying the latitudinal effect. The latitudinal effect is the change in the species’ growth rate during migration. Mark–recapture data (N = 1635, latitude 22.21°S–34.00°S) presents northerly movement of the eastern king prawn, with New South Wales prawns showing substantial average movement of 140 km (standard deviation: 176 km) north. A generalized von Bertalanffy growth model framework is used to incorporate the latitudinal effect together with the canonical seasonal effect. Applying this method to eastern king prawn mark–recapture data guarantees consistent estimates for the latitudinal and seasonal effects. For M. plebejus, it was found that growth rate peaks on 25 and 29 January for males and females, respectively; is at a minimum on 27 and 31 July, respectively; and that the shape parameter, k (per year), changes by –0.0236 and –0.0556 every 1 degree of latitude south increase for males and females, respectively.

Pathological and molecular genetic variation in the interaction between Sporobolus spp. and Bipolaris spp.

1999 ◽  
Vol 50 (4) ◽  
pp. 583 ◽  
Author(s):  
S. D. Hetherington ◽  
J. A. G. Irwin
Keyword(s):  
Fungal Pathogens ◽  
Biological Control Agent ◽  
New South ◽  
Molecular Genetic ◽  
Control Agent ◽  
Banding Patterns ◽  
South Wales ◽  
False Smut ◽  
Molecular Genetic Variation ◽  
Diverse Plant

Members of the Sporobolus indicus complex, particularly Sporobolus indicus (L.) R. Br. var. major (Buse) Baaijens (Giant Parramatta Grass; GPG) and S. pyramidalis P. Beauv. (Giant Rat’s Tail Grass; GRTG), are serious pastoral weeds in coastal areas of Australia. Ovariicolous fungal pathogens from the genus Bipolaris Shoem. are agents of the disease false smut on these plants. The hosts are morphologically plastic and variation in disease susceptibility may affect the use of the fungus as a biological control agent. Variation was investigated by screening 22 clones representative of 5 taxonomic entities within the S. indicus complex with 39 fungal isolates representative of 4 Bipolaris species. Both weed entities were highly susceptible to B. ravenelii and B. crustacea and only slightly susceptible to B. cylindrica and B. australis. The converse was true for other Sporobolus entities tested. Genomic DNA was extracted from 20 Sporobolus clones (genotypes) and the RAPD technique used to generate an index of variation. This technique was able to separate the members of the complex into taxonomic groupings. There was only a 2% difference in banding patterns of S. indicus var. major clones collected in New South Wales. Variation amongst clones of S. pyramidalis was greater (15%), indicating a more genetically diverse plant population. The more variable genetic background of S. pyramidalis is more likely to provide variation in susceptibility than that of S. indicus var. major

Reproduction of Pseudomys novaehollandiae (Muridae) in the Wild

1980 ◽  
Vol 7 (3) ◽  
pp. 385 ◽  
Author(s):  
CM Kemper
Keyword(s):  
Breeding Season ◽  
New South ◽  
Reproductive Organs ◽  
First Year ◽  
Reproductive Condition ◽  
South Wales ◽  
In The Wild ◽  
Males And Females ◽  
Preputial Glands ◽  
Breeding Seasons

A total of 291 P. novaehollandiae were observed during a 4-y study in the Nelson Bay and Smith Lake regions of New South Wales. Reproductive organs were examined from males and females, May 1972-May 1974; reproductive condition of females was noted during a CMR study, August 1974-July 1976. Breeding seasons (conceptions and births) occurred between August and early January (4-5 months) in the first 3 years and between September and March (7 months) in the last year. Second-year females produced three or four litters in short seasons, four or five litters in the long season and up to 20 offspring per season. First-year females produced one litter in short seasons and one or two litters in the long season. Mean litter size was 4.56 (2-6). Ovarian follicles were largest in September and smallest in May. Small, inactive CL persisted in parous females until May. Placental scars were present in all sampled months. Vaginae remained closed during the non-breeding season. In mature males testes and epididymides contained sperm from July to March. Vesicular, prostate and preputial glands were enlarged and secretory from September to December. Testes were smallest and least developed in May and June. Males were divided into five categories depending on age and overall reproductive condition. Sexual maturity was reached in the breeding season of birth by some males (33%) and females (13-88%). More females matured early when population density was low. Food abundance and quality may have been important variables in regulating the timing of the breeding season.

Sex-Ratios and Related Characteristics in Spinifex sericeus (Poaceae)

1990 ◽  
Vol 38 (2) ◽  
pp. 153 ◽  
Author(s):  
KM Maze ◽  
RDB Whalley
Keyword(s):  
Sex Ratio ◽  
New Caledonia ◽  
New South ◽  
Sand Dunes ◽  
Sex Ratios ◽  
Experimental Period ◽  
North Coast ◽  
Male Bias ◽  
South Wales ◽  
Males And Females

Spinifex sericeus R.Br. is a dioecious, stoloniferous grass which occurs on sand dunes around much of the south-eastern coastline of Australia, New Zealand and New Caledonia. Sex ratios of ramets of S. sericeus and some associated characteristics were studied on the mid-north coast of New South Wales. Generally there was a male bias in the observed ramet sex ratio, although the extent of this bias varied with the beach investigated, the position in the dunes and the time of sampling. Male inflorescences matured and died more rapidly than females, and hence the observed male bias was greatest at the beginning of the flowering period. Male ramets were found to have more sexual tillers per clump than female ramets. The genet sex ratio was estimated from plants grown from seed and separated from each other throughout the experimental period. Males and females were found to be equal in number, although this equality may not be a true reflection of the genet sex ratio in the field.

Influences of weather and time of day on trap catches of bush fly,Musca vetustissima Walker (Diptera: Muscidae)

1986 ◽  
Vol 76 (3) ◽  
pp. 359-366 ◽  
Author(s):  
W. G. Vogt
Keyword(s):  
Wind Speed ◽  
Relative Humidity ◽  
Solar Radiation ◽  
New South ◽  
Time Of Day ◽  
Weather Variables ◽  
South Wales ◽  
Males And Females ◽  
Catch Rates ◽  
Trap Catches

AbstractField populations of Musca vetustissima Walker were sampled in a region of New South Wales at 2-h intervals on 35 occasions between spring 1984 and autumn 1985 using wind-oriented fly traps. Ambient temperature, solar radiation, relative humidity and wind speed explained 84·3% of the within-day deviance of total catches (both sexes combined). Temperature and solar radiation jointly explained 82·6% of this deviance (71·1 and 11·5%, respectively), indicating that the other variables, although significant, did not greatly affect trap catches. As air temperature increased, log catch rates increased non-linearly up to a maximum at 27·5°C and declined thereafter. Log catch rates increased linearly as solar radiation increased and declined linearly as relative humidity and wind speed increased. Changes in log catch rates with time of day were explained almost entirely by the four weather variables, i.e. when weather effects were removed, time of day effects were no longer significant. These weather variables also accounted for 79·9% of the between-day variation in logarithms of trap catches. Relative responses of males and females to traps differed significantly with respect to relative humidity, wind speed and time of day. Male catches tended to increase relative to female catches between 1200 h and 1800 h and also declined more slowly with increases in relative humidity and wind speed. Separate models are presented for standardization of male and female catch rates; the estimates differ from those obtained from observed sex ratios and total catch rates, but the differences are small compared to the observed day-to-day variation in catch rates.

Diet of the Murray Turtle, Emydura-Macquarii (Gray) (Testudines, Chelidae)

1986 ◽  
Vol 13 (1) ◽  
pp. 65 ◽  
Author(s):  
BC Chessman
Keyword(s):  
Aquatic Macrophytes ◽  
Aquatic Invertebrates ◽  
New South ◽  
Stomach Contents ◽  
Filamentous Algae ◽  
Terrestrial Invertebrates ◽  
Dietary Shift ◽  
South Wales ◽  
Murray River ◽  
Males And Females

Examination of the stomach contents of 122 E. macquarii from the Murray River, Lake Boga and other waters in northern Victoria and southern New South Wales showed that this species is an opportunistic omnivore. In order of decreasing importance the main food types were filamentous algae, vertebrate (mainly fish) carrion, detritus, periphyton (including sponges), mobile aquatic invertebrates, aquatic macrophytes and terrestrial invertebrates. There was a degree of dietary shift with turtle size, small specimens containing more detritus and periphyton and less filamentous algae, macrophytes and carrion than bigger ones. The diets of mature males and females did not differ appreciably. Diel changes in stomach content volumes indicated that E. macquarii feeds mainly during the daytime.

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