Studies of Macropodidae in Queensland. 6. Sex determination of adult skulls of the grey kangaroo and the red kangaroo

Discriminant functions to determine the sex of adult skulls of the grey and the red kangaroos are presented. The measurements used are basal length of skull and molar index, and discrimination due to length is significant at the 1% level

Studies of Macropodidae in Queensland. 3. Reproduction in the grey kangaroo (Macropus major) in Southern Queensland

Reproduction in the grey kangaroo has been studied in captivity and in two field populations. In captive animals, the oestrous cycle ranged from 41 to 43 days and the gestation period from 35 to 38 days. Pouch life of the young averaged 297 days; the interval between successive births, in the absence of a delayed embryo, averaged 356 days. Delayed embryos in captive females were produced at an oestrus occurring between 112 and 243 days after a birth; the delayed birth normally occurred when the first pouch young was between 291 and 312 days old. Female kangaroos in the field commenced reproductive activity at ages ranging from 17 to 28 months, with reduced fertility in old age (over 16 years). Delayed embryos were seldom found in field-collected kangaroos and only in those with pouch young older than 174 days. No defined breeding season was apparent, though more young were conceived during October-December than at other times. Approximately 50% of young failed to reach independence. Young suckled until 18 months of age both in captivity and in the field. Males were observed to be reproductively effective between the ages of 3 and 15 years

Studies of Macropodidae in Queensland. 5. Effects of drought on reproduction in the grey kangaroo (Macropus giganteus).

Reproductive activity and survival of pouch young were studied in a population of the grey kangaroo (Macropus giganteus Shaw) in the St. George district, southern Queensland, during a drought extending from September 1964 to December 1965. After 8 months of drought, reproductive activity virtually ceased and death of pouch young began to occur; reproduction did not return to normal until the drought broke. No young born between September 1964 and November 1965 survived the drought, and it is anticipated that for some years this will be reflected in population samples from this district

The mitotic chromosomes of a macropod hybrid

In a yard at Hermitage Research Station, Warwick, a male agile wallaby (Wallabia agilis (Gould)) was observed mating with two female red kangaroos (Megaleia rufa (Desmarest)) and by late 1970 these females were carrying furred pouch young of phenotypic appearance intermediate between the species. A mitotic chromosome count of 2n = 18 was obtained for both progeny, male and female, of Wallabia agilis (Gould), (2n = 16) x Megaleia rufa (Desmarest), (2n = 20)

Coupled Hartree-Fock-Bogoliubov kinetic equations for a trapped Bose gas

Using the Kadanoff-Baym non-equilibrium Green's function formalism, we derive the self-consistent Hartree-Fock-Bogoliubov (HFB) collisionless kinetic equations and the associated equation of motion for the condensate wavefunction for a trapped Bose-condensed gas. Our work generalizes earlier work by Kane and Kadanoff (KK) for a uniform Bose gas. We include the off-diagonal (anomalous) pair correlations, and thus we have to introduce an off-diagonal distribution function in addition to the normal (diagonal) distribution function. This results in two coupled kinetic equations. If the off-diagonal distribution function can be neglected as a higher-order contribution, we obtain the semi-classical kinetic equation recently used by Zaremba, Griffin and Nikuni (based on the simpler Popov approximation). We discuss the static local equilibrium solution of our coupled HFB kinetic equations within the semi-classical approximation. We also verify that a solution is the rigid in-phase oscillation of the equilibrium condensate and non-condensate density profiles, oscillating with the trap frequency.Comment: 25 page

On the complexity of strongly connected components in directed hypergraphs

We study the complexity of some algorithmic problems on directed hypergraphs and their strongly connected components (SCCs). The main contribution is an almost linear time algorithm computing the terminal strongly connected components (i.e. SCCs which do not reach any components but themselves). "Almost linear" here means that the complexity of the algorithm is linear in the size of the hypergraph up to a factor alpha(n), where alpha is the inverse of Ackermann function, and n is the number of vertices. Our motivation to study this problem arises from a recent application of directed hypergraphs to computational tropical geometry. We also discuss the problem of computing all SCCs. We establish a superlinear lower bound on the size of the transitive reduction of the reachability relation in directed hypergraphs, showing that it is combinatorially more complex than in directed graphs. Besides, we prove a linear time reduction from the well-studied problem of finding all minimal sets among a given family to the problem of computing the SCCs. Only subquadratic time algorithms are known for the former problem. These results strongly suggest that the problem of computing the SCCs is harder in directed hypergraphs than in directed graphs.Comment: v1: 32 pages, 7 figures; v2: revised version, 34 pages, 7 figure

Studies of macropodidae in Queensland. 8. Age estimation in the red kangaroo (Megaleia rufa (Desmarest))

Methods of estimating the age of pouch young of the grey kangaroo (Macropus giganteus Shaw), the eastern wallaroo ( Osphranter robustus (Gould) ) and the red-necked wallaby (Wallabia rufogrisea (Desmarest)) from length of tail and hind feet, and regressions relating age to an index of progression of the molar teeth (Kirkpatrick 1964) for adults of these species and the red kangaroo (Megaleia rufa (Desmarest)), have been published (Kirkpatrick 1965)

Studies of Macropodidae in Queensland. 1. Food preferences of the grey kangaroo (Macropus major Shaw)

1. Frequency of plant species available in the study pasture was compared with the frequency of species retained in the mouths of grey kangaroos (Macropus major Shaw) shot while feeding

Technical notes. Benzene hexachloride in pineapple fields

Scarabaeid larvae have been found associated with root damage to pineapple plants in various coastal localities in Queensland. Where a recommendation of BHC in the soil as a control method might reasonably have been made from work on other crops in the same localities, a consideration of possible tainting of the fruit has prevented this