Divergent environments and population bottlenecks fail to generate premating isolation in Drosophila pseudoobscura

While the feasibility of bottleneck-induced speciation is in doubt, population bottlenecks may still affect the speciation process by interacting with divergent selection. To explore this possibility, I conducted a laboratory speciation experiment using Drosophila pseudoobscura involving 78 replicate populations assigned in a two-way factorial design to both bottleneck (present vs. absent) and environment (ancestral vs. novel) treatments. Populations independently evolved under these treatments and were then tested for assortative mating and male mating success against their common ancestor. Bottlenecks alone did not generate any premating isolation, despite an experimental design that was conducive to bottleneck-induced speciation. Premating isolation also did not evolve in the novel environment treatment, neither in the presence nor absence of bottlenecks. However, male mating success was significantly reduced in the novel environment treatment, both as a plastic response to this environment and as a result of environment-dependent inbreeding effects in the bottlenecked populations. Reduced mating success of derived males will hamper speciation by enhancing the mating success of immigrant, ancestral males. Novel environments are generally thought to promote ecological speciation by generating divergent natural selection. In the current experiment, however, the novel environment did not cause the evolution of any premating isolation and it reduced the likelihood of speciation through its effects on male mating success.

Toxinology in Australia's colonial era: A chronology and perspective of human envenomation in 19th century Australia

The medical management of those envenomed by snakes, spiders and poisonous fish in Australia featured extensively in the writings 19th century doctors, expeditioners and anthropologists. Against the background of this introduced medical doctrine there already existed an extensive tradition of Aboriginal medical lore; techniques of heat treatment, suction, incision and the application of plant-derived pharmacological substances featured extensively in the management of envenomed victims. The application of a hair-string or grass-string ligature, suctioning of the bite-site and incision were practised in a variety of combinations. Such evolved independently of and pre-dated such practices, which were promoted extensively by immigrant European doctors in the late 19th century. Pacific scientific toxinology began in the 17th century with Don Diego de Prado y Tovar's 1606 account of ciguatera. By the end of the 19th century more than 30 papers and books had defined the natural history of Australian elapid poisoning. The medical management of snakebite in Australia was the focus of great controversy from 1860 to 1900. Dogmatic claims of the supposed antidote efficacy of intravenous ammonia by Professor G.B. Halford, and that of strychnine by Dr. Augustus Mueller, claimed mainstream medical attention. This era of potential iatrogenic disaster and dogma was brought to a conclusion by the objective experiments of Joseph Lauterer and Thomas Lane Bancroft in 1890 in Brisbane; and by those of C.J. Martin (from 1893) and Frank Tidswell (from 1898), both of Sydney. The modern era of Australian toxinology developed as a direct consequence of Calmette's discovery, in Paris in 1894, of immune serum, which was protective against snakebite. We review the key contributors and discoveries of toxinology in colonial Australia.

'Nothing good ever came out of Japan': Race-mixing and the limits of diaspora

This paper argues that postcolonial notions of diaspora are premised on immigrant subjectivities and standpoints which do not fully apprehend the mixed-race / bi-racial experience and the local effect of cultural hybridity in Western settings. The paper was prompted by a recent conversation with Dee, the daughter of a Japanese warbride. As a child Dee recalled being told by her friend's mother that 'nothing good ever came out of Japan'. The significance of constant interpolations into 'Asianness' by statements such as these; by the 'where do you come from?' question and by more blatant discriminations are inadequately addressed by traditional and postcolonial notions of diaspora. 'Roots' and 'routes' imagery feature prominently in discussions of diaspora and hybridity which aim to decolonise culture and identity in deconstructive moves that highlight their flexible, multiple, contractedness. While it has been argued that even these conceptualisations are problematic because they privilege orders of explanation, theory and standpoint that are forced back into line with traditional notions of discrete 'races', cultures, ethnicities and identities, cultural studies and postcolonial theorists do not appear to find this contradiction overly troubling. Lodged in bodies that do not easily conflate to neat either/or cultures, politics and genetics, race-mixing also defies and yet return us to culture and biology. However, I argue that their refractions though the same tired old orders of racial, ethnic, cultural and national differentiation prevent us from disregarding the discursive effects of racism and racialisation.

Implementation of Triple P-Positive Parenting Program in Hong Kong: Predictors of programme completion and clinical outcomes

This study examined the effectiveness of the Triple P-Positive Parenting Program in a government child health service delivery context with Chinese parents in Hong Kong. Specifically, the study sought to identify pre-intervention variables that might predict programme outcomes such as, level of clinical improvement and programme completion. Participants were 661 parents of pre-school and primary aged children participating in a group version of the Triple P-Positive Parenting Program. There were significant decreases in disruptive child behaviours, levels of parenting stress, general stress and anxiety and an increase in parenting sense of competence. Greater change in reports of child behaviour problems was related to lower levels of family income, new immigrant family status, and higher pre-intervention levels of parenting stress. The present study provides a profile of parents who are most likely to benefit from parent training programmes.