Decreased relatedness between male prickly forest skinks (Gnypetoscincus queenslandiae) in habitat fragments

In species with low levels of dispersal the chance of closely related individuals breeding may be a potential problem; sex-biased dispersal is a mechanism that may decrease the possibility of cosanguineous mating. Fragmentation of the habitat in which a species lives may affect mechanisms such as sex-biased dispersal, which may in turn exacerbate more direct effects of fragmentation such as decreasing population size that may lead to inbreeding depression. Relatedness statistics calculated using microsatellite DNA data showed that rainforest fragmentation has had an effect on the patterns of dispersal in the prickly forest skink (Gnypetoscincus queenslandiae), a rainforest endemic of the Wet Tropics of north eastern Australia. A lower level of relatedness was found in fragments compared to continuous forest sites due to a significantly lower level of pairwise relatedness between males in rainforest fragments. The pattern of genetic relatedness between sexes indicates the presence of male-biased dispersal in this species, with a stronger pattern detected in populations in rainforest fragments. Male prickly forest skinks may have to move further in fragmented habitat in order to find mates or suitable habitat logs.

Experience overrides colour in lizard contests

We examined the role of conspicuous coloration in male-male contests for two species of Australian dragon lizards, Ctenophortis decresii and C. vadnappa, in which conspicuous coloration has a demonstrated predation cost. We conducted contests in which the overall conspicuousness of male coloration was manipulated using paints that matched the spectral reflectance of the lizards, as well as natural (control) contests. There was little evidence for an influence of colour on contest outcome or aggression levels for either species when all experiments were considered. However, we found a significant effect of trial order and experience on contest outcome and aggression levels (the same pair of males was used for both types of contest), despite a 2-3 week interval between contests. When we examined only the first trial between unfamiliar males, we found that male C. vadnappa that had been painted to appear more conspicuous consistently won. Comparison with the natural trials suggests that the aspect of colour manipulation that was responsible for this result was the 'hue' of the throat: males with yellower throats consistently beat males with bluer throats in both natural and painted trials. The difference in coloration of flank markings also predicted the difference in aggression scores between contestants in the natural trials. These results suggest that although colour is important in opponent assessment and in determining contest outcome in C vadnappa, previous agonistic experience can override the effects of colour and have a long-lasting influence on aggressive behaviour.

The competitive Darwin

Although Darwin was not the first to conceive directional selection as a mechanism of phenotypic change, it is his ideas that were received, and that have shaped population biology to this day. A significant change in his theoretical orientation occurred in the mid-1850s. About then he abandoned environmental selection in favor of competitive selection, and adopted relative adaptation with all its consequences as an alternative. These ideas changed his thinking fundamentally and shaped his argument throughout the writing of his great book. It is still these ideas that predominate today. Here I examine Darwin ' s ideas in relation to his principle of divergence, sexual selection, and the nature and origin of species. Finally I suggest that had he not misunderstood the function of sexual communication he might well have understood the nature of species and provided a more penetrating resolution to Herschell ' s mystery of mysteries, with which he opened his book.

Who wants to live forever?

For millennia, human civilization has been fascinated with overcoming death. Immortality, eternal youth or at least the prospect of reaching biblical age have had a strong lure for religion, art and popular beliefs. Life after death, which is, in essence, eternal life, is the one central element of nearly all religions since Ancient Egypt. If we believe the Old Testament, some of the patriarchs lived for several hundreds of years. In the medieval ages, the fountain of youth was a popular myth, often illustrated in paintings, such as Lucas Cranach's The Fountain of Youth (Fig 1). And society today has not lost its fascination with immortality, as seen in Hollywood movies such as the Highlander films (1986–2000), The 6th Day (2000) or Indiana Jones and the Last Crusade (1989), and novels such as H. Rider Haggard's She. But for the first time, modern science may provide the knowledge and tools to interfere with the ageing processes and fulfil this age-old dream. This possibility has triggered an intense debate among scientists and ethicists about the potential of anti-ageing therapies and their ethical and social consequences. Given that anti-ageing therapies could dramatically change the social fabric of modern societies, it is quite astonishing that these debates have neglected the views of the larger public.

Identification of new flaviviruses in the Kokobera virus complex

Novel flavivirus isolates from mosquitoes collected in northern Australia were analysed by partial genomic sequencing, monoclonal antibody-binding assays and polyclonal cross-neutralization tests. Two isolates were found to be antigenically distinct from, but related to, viruses of the Kokobera virus complex, which currently contains Kokobera (KOKV) and Stratford (STRV) viruses. Nucleotide sequence comparison of two separate regions of the genome revealed that an isolate from Saibai Island in the Torres Strait in 2000 (TS5273) was related closely to KOKV and STRV, with 74-80 and 75-76% nucleotide similarity, respectively. An isolate from mainland Cape York in 1998 (CY1014) was found to be more divergent from KOKV and STRV, with

The importance of being physical in the middle years

Young people are physical (as are adults) and their bodies are significant in relation to who they are, what and how they learn, and who they can become. Consistent with middle schooling philosophy, but often not reflected in practice, a balanced approach to all aspects of the growth and development of young people is supported. Much research has shown the middle years is an important time assigned to 'identity development' and 'physical development' while it is also a time when many young people become less physically active and less engaged in learning at school. This paper reviews current research about physical activity, physical education and physicality in order to locate the place of the physical in the lives of young people and encourage practices in the middle years that acknowledge this physicality.

Optimal strategies in political elections

In the Majoritarian Parliamentary System, the government has a constitutional right to call an early election. This right provides the government a control to achieve its objective to remain in power for as long as possible. We model the early election problem mathematically using opinion polls data as a stochastic process to proxy the government's probability of re-election. These data measure the difference in popularity between the government and the opposition. We fit a mean reverting Stochastic Differential Equation to describe the behaviour of the process and consider the possibility for the government to use other control tools, which are termed 'boosts' to induce shocks to the opinion polls by making timely policy announcements or economic actions. These actions improve the government's popularity and have some impact upon the early-election exercise boundary. © Austral. Mathematical Soc. 2005.

The new age: Towards a market model

The problem of how the New Age may be defined is widely acknowledged among commentators. It is hard to delineate and does not fit easily into existing analytical categories. This paper will review how scholars have conceptualised the movement. It will discuss the problems inherent in attempting to specify its constituents, fix its limits, and characterise its organisational forms. The later sections advances the argument that some of its most distinctive characteristics may be accounted for by acknowledging the market dynamics at play in New Age milieux. It is proposed that the diffuse overall shape of the movement is the result of determinate commercial institutional arrangements.