Reproductive conflict delays the recovery of an endangered social species

Evolutionary theory predicts that individuals, in order to increase their relative fitness, can evolve behaviours that are detrimental for the group or population. This mismatch is particularly visible in social organisms. Despite its potential to affect the population dynamics of social animals, this principle has not yet been applied to real-life conservation. Social group structure has been argued to stabilize population dynamics due to the buffering effects of nonreproducing subordinates. However, competition for breeding positions in such species can also interfere with the reproduction of breeding pairs. Seychelles magpie robins, Copsychus sechellarum, live in social groups where subordinate individuals do not breed. Analysis of long-term individual-based data and short-term behavioural observations show that subordinates increase the territorial takeover frequency of established breeders. Such takeovers delay offspring production and decrease territory productivity. Individual-based simulations of the Seychelles magpie robin population parameterized with the long-term data show that this process has significantly postponed the recovery of the species from the Critically Endangered status. Social conflict thus can extend the period of high extinction risk, which we show to have population consequences that should be taken into account in management programmes. This is the first quantitative assessment of the effects of social conflict on conservation.

Climate vs. soil factors in local adaptation of two common plant species

Evolutionary theory suggests that divergent natural selection in heterogeneous environments can result in locally adapted plant genotypes. To understand local adaptation it is important to study the ecological factors responsible for divergent selection. At a continental scale, variation in climate can be important while at a local scale soil properties could also play a role. We designed an experiment aimed to disentangle the role of climate and ( abiotic and biotic) soil properties in local adaptation of two common plant species. A grass (Holcus lanatus) and a legume ( Lotus corniculatus), as well as their local soils, were reciprocally transplanted between three sites across an Atlantic-Continental gradient in Europe and grown in common gardens in either their home soil or foreign soils. Growth and reproductive traits were measured over two growing seasons. In both species, we found significant environmental and genetic effects on most of the growth and reproductive traits and a significant interaction between the two environmental effects of soil and climate. The grass species showed significant home site advantage in most of the fitness components, which indicated adaptation to climate. We found no indication that the grass was adapted to local soil conditions. The legume showed a significant home soil advantage for number of fruits only and thus a weak indication of adaptation to soil and no adaptation to climate. Our results show that the importance of climate and soil factors as drivers of local adaptation is species-dependent. This could be related to differences in interactions between plant species and soil biota.

First steps in experimental cancer evolution

Evolutionary processes play a central role in the development, progression and response to treatment of cancers. The current challenge facing researchers is to harness evolutionary theory to further our understanding of the clinical progression of cancers. Central to this endeavour will be the development of experimental systems and approaches by which theories of cancer evolution can be effectively tested. We argue here that the experimental evolution approach – whereby evolution is observed in real time and which has typically employed microorganisms – can be usefully applied to cancer. This approach allows us to disentangle the ecological causes of natural selection, identify the genetic basis of evolutionary changes and determine their repeatability. Cell cultures used in cancer research share many of the desirable traits that make microorganisms ideal for studying evolution. As such, experimental cancer evolution is feasible and likely to give great insight into the selective pressures driving the evolution of clinically destructive cancer traits. We highlight three areas of evolutionary theory with importance to cancer biology that are amenable to experimental evolution: drug resistance, social evolution and resource competition. Understanding the diversity, persistence and evolution of cancers is vital for treatment and drug development, and an experimental evolution approach could provide strategic directions and focus for future research.

The effect of mood on opposite-sex judgments of males' commitment and females sexual intent

Gender differences in perceptions of sexual intent and commitment have been the subject of formal and informal inquiry for considerable time. One evolutionary theory, Error Management Theory (EMT), predicts that opposite-sex perceptions of female sexual intent and male commitment intent reflect intrinsic biases that minimize gender-specific evolutionary costs. The results supporting these hypotheses were obtained from subjects regardless of mood. We hypothesized that mood would influence ratings of sexual and commitment intent. Sixty participants (30 males, 30 females) were recruited and exposed to a positive and negative mood condition in counterbalanced groups using video stimuli. Preliminary analyses found an unexpected effect of order of mood induction, necessitating separate analyses of the Positive-Negative (PN) and Negative-Positive (NP) groups. Contrary to the original study, there were no gender effects. Positive moods led to increased ratings of both sexual and commitment intent across genders. Further, negative to positive mood-change was associated with significantly increased ratings. Both males and females attributed significantly higher sexual intent to same-sex rivals than themselves, but only males assessed themselves as having significantly higher commitment intent than same-sex rivals. The EMT model may require adaptation to acknowledge effects of variables such as mood on its predictions of gender-specific biases.

Does testosterone mediate the trade-off between nestling begging and growth in the canary (Serinus canaria)?

Nestling birds solicit food from their parents with vigorous begging displays, involving posturing, jostling and calling. In some species, such as canaries, begging is especially costly because it causes a trade off against nestling growth. Fitness costs of begging like this are predicted by evolutionary theory because they function to resolve conflicts of interest within the family over the provision of parental investment. However, the mechanism that links these costs with nestling behaviour remains unclear. In the present study, we determine if the relationships between nestling androgen levels, nestling begging intensities and nestling growth rates are consistent with the hypothesis that testosterone is responsible for the trade-off between begging and growth. We test this idea with a correlational study, using fecal androgens as a non-invasive method for assaying nestling androgen levels. Our results show that fecal androgen levels are positively correlated with nestling begging intensity, and reveal marked family differences in each trait. Furthermore, changes in fecal androgen levels between 5 and 8 days after hatching are positively associated with changes in nestling begging intensity, and negatively associated with nestling growth during this time. Although these correlational results support our predictions, we suggest that that experimental manipulations are now required to test the direct or indirect role of testosterone in mediating the trade-off between begging and growth.

Frequency-dependent physiological trade-offs between competing colour morphs

Evolutionary theory suggests that alternative colour morphs (i.e. genetically controlled phenotypes) may derive similar fitness under frequency-dependent selection. Here we experimentally demonstrate opposing effects of frequency-dependent social environments on plasma hormone levels (testosterone and corticosterone) and immune function between red- and black-headed male morphs of the Gouldian finch (Erythrura gouldiae). Red-headed males are highly sensitive to changes in the social environment, especially towards the relative density of their own aggressive morph, exhibiting high stress responses and immunosuppression in socially competitive environments. In contrast, the non-aggressive black-headed males follow a more passive strategy that appears to buffer them against social stresses. The differential effect of hormones on aggressive behaviour and immune performance reinforces the contrasting behavioural strategies employed by these colour morphs, and highlights the importance of the social environment in determining the individual basis of behavioural and physiological responses.

Exploratory surgery of the female psyche

The thesis explores the visual narrative concerning a journey of empowerment for women. To enable the journey to advance the inquiry is directed into two areas. The first area is female gender, which is argued to be socially constructed and implicit in the marginalisation of women in western society. The second area is ‘feminine authority’, which is gained by developing an understanding and acceptance of the characteristics which have historically been considered as belonging to the feminine. Granting these characteristics agency would recognise their authority and assist in the elevation of the female to a position of equality in western society. Beginning from a feminist position, the research supported the belief that the female is marginalised in western society. It also confirmed the notion that empowerment and authority can be attained by women if they actively pursue the following; • Explore their own psychology beyond the existing socially constructed gender roles. • Develop an understanding of their feminine self by applying Jung's theories on individuation and archetypes. • Expose the underlying patriarchal influence in western epistemology and science by challenging existing deeply held cultural and scientific beliefs and by actively contributing as feminists to the areas of epistemology and science. Archetypal myths of the ‘feminine’ have developed from an androcentric position. They enforce and perpetuate gender imbalance which contributes to the disenfranchisement of women in western society, ‘Individuation’ is a process in which a person explores aspects of themselves to bring forth parts of their unconscious into their conscious mind in an attempt to gain a deeper understanding of themselves. As a consequence the consciousness develops closer links with archetypal memories which assists the exploration. The ‘true feminine’ is the feminine not restricted or defined by the dominant androcentric view. Knowledge of the feminine empowers women to address the marginalisation of the female in western society and assists in the process of gaining female authority. This enquiry also investigated the four stages of female psychological development with regard to patriarchal influences. Of particular importance is the second stage of psychological development where the female identifies with historically perceived inferior characteristics of the female. This is when she rejects her connections with the primacy of female power and her deep connections with nature which were inherited from archaic times. It is at this stage that she absorbs the myths associated with western patriarchal society which effectively disempower her. Western epistemology, with its emphasis on ‘objective’ investigation and empiricism contributes to the support for and promotion of ‘inferior’ female gender. This type of investigation is brought into question when areas of research into primates and human evolutionary theory is shown to develop from an androcentric view. Western knowledge has associations with power and justice and power is commonly associated with dominance. Regard for ‘truth’ and ‘absolute’ can be viewed as key elements in the support for knowledge and its associations with power. Knowledge has historically maintained suppression of individual experience which promotes a universalised account. This suppression of beliefs other than the dominant authority maintains the existing dominant social structure. Foucault's view of the genderised or inscribed body alerts us to areas where dominance, resistance and power play a part in maximising masculine power and control. Gender becomes an instrument of power within the existing patriarchal structure. Gender, knowledge and power are identified as areas obstructing female empowerment. Part 3 of this exegesis examines the imagery which embodies the visual narrative. Particularly, the harlequin image, its historical background and connections with ancient mythology including reference to Jungian psychology. The harlequin image is developed sequentially in the earlier black and white drawings on paper. These drawings contained a female figure which was often placed in juxtaposition with a Venus or goddess image, reference was also made to ‘eve’ and the ‘siren’. These elements provided the framework which enabled the harlequin image to emerge and evolve. The narrative developed with an understanding of the ‘feminine’ aspects of the psyche which resulted in the harlequin acquiring the elevated authority of a goddess. The Harlequin evolved from my need for symbolic representation of the female psyche. It represents contradiction and dualism. It is a composition of opposites, reflects masculine and feminine traits, the dark and light of the conscious and unconscious mind, it houses both comic and sinister elements, is a trickster and menace. The costume, colours and patterns are expressive elements conducive to fragmentation and layering within the composition of the paintings. Jung examined the harlequin in Picasso's paintings. He concluded that as Picasso drew on his inner experiences the harlequin became important as a symbol; it was a pictorial representation from the unconscious psyche. It travelled freely from the conscious to the unconscious and represented the masculine and feminine, chthonian and apollonian. The final painting in the series, a triptych, completes the narrative and stands alone as a salutatory work. It unites the series by combining existing compositional devices and technique while making reference to imagery from previous works, ‘The Three Graces Victorious’, expresses the authority of the feminine. It completes a victorious stage of a journey where the harlequin is empowered by archaic memories and knowledge of the psyche. The feminine is hailed, elevated and venerated. Other elements which assist in expressing the visual narrative are; colour, technique and influence. Colour is explored and its use as an emotive devise in expressionism. Paul Klee's writing on the use of colour and it's symbolic meaning and Julia Kristeva's investigation on colour from a psychoanalytic and semiotic view are also discussed. To indicate influences and connections within my oeuvre, reference is also made to the following: Jasper Johns' for his use of imagery in his ‘Four Seasons’ series with it's reference to a journey of maturation and Louise Bourgeois' work which deals with issues of gender, memories and past journeys. Although ‘The Three Graces Victorious’; the concluding painting for the investigation is celebratory and represents a finality to the thesis, it points to further areas that impede feminine development and need future examination. Reference is made to a continuation of the exploratory journey by plotting the Harlequin/Goddesses future directions. Although the Harlequin/Goddess is empowered with newly acquired authority, her future journey does not need to be bound by mathematics or limited by rationality. She does not require power to dominate or gender structures to subjugate, but requires limitless boundaries and contexts. The Harlequin/Goddess's future journey is not fixed.

Fine-scale adaptation in a clonal sea anemone

Local adaptation in response to fine-scale spatial heterogeneity is well documented in terrestrial ecosystems. In contrast, in marine environments local adaptation has rarely been documented or rigorously explored. This may reflect real or anticipated effects of genetic homogenization, resulting from widespread dispersal in the sea. However, evolutionary theory predicts that for the many benthic species with complex life histories that include both sexual and asexual phases, each parental habitat patch should become dominated by the fittest and most competitive clones. In this study we used genotypic mapping to show that within headlands, clones of the sea anemone Actinia tenebrosa show restricted distributions to specific habitats despite the potential for more widespread dispersal. On these same shores we used reciprocal transplant experiments that revealed strikingly better performance of clones within their natal rather than foreign habitats as judged by survivorship, asexual fecundity, and growth. These findings highlight the importance of selection for fine-scale environmental adaptation in marine taxa and imply that the genotypic structure of populations reflects extensive periods of interclonal competition and site-specific selection.

Sex-dependent selection differentially shapes genetic variation on and off the guppy Y chromosome

Because selection is often sex-dependent, alleles can have positive effects on fitness in one sex and negative effects in the other, resulting in intralocus sexual conflict. Evolutionary theory predicts that intralocus sexual conflict can drive the evolution of sex limitation, sex-linkage, and sex chromosome differentiation. However, evidence that sex-dependent selection results in sex-linkage is limited. Here, we formally partition the contribution of Y-linked and non-Y-linked quantitative genetic variation in coloration, tail, and body size of male guppies (Poecilia reticulata)—traits previously implicated as sexually antagonistic. We show that these traits are strongly genetically correlated, both on and off the Y chromosome, but that these correlations differ in sign and magnitude between both parts of the genome. As predicted, variation in attractiveness was found to be associated with the Y-linked, rather than with the non-Y-linked component of genetic variation in male ornamentation. These findings show how the evolution of Y-linkage may be able to resolve sexual conflict. More generally, they provide unique insight into how sex-specific selection has the potential to differentially shape the genetic architecture of fitness traits across different parts of the genome.

Sex and death: CHD1Z associated with high mortality in moorhens

Sex ratios in clutches of moorhens (Gallinula chloropus) in Britain were measured on 83 chicks using the sex-linked CHD1 gene (Chromo-helicase/ATPase-DNA binding protein 1). Among birds, the female is the hetero-gametic sex (Z and W chromosomes), and the male is homogametic (two copies of the Z chromosome). We report variation among the PCR-amplified fragments of the CHD1Z, and the death of nearly all heterozygous male chicks (92%). In contrast, survivorship among females and homozygote males was 54–60%. Mortality in male heterozygotes was significantly higher than that of male homozygotes (P < 0.001). Chick and egg biometrics were not significantly different between these males. The CHD1Z was unlikely to be directly responsible but may have been hitchhiked by the causal gene(s). The observations appear to follow a classic underdominance (heterozygote inferiority) pattern, but raise the paradoxical question of why one form of the Z chromosome has not been fixed, as is expected from evolutionary theory. We discuss possible explanations and include a survey of British populations based on skin specimens.

Economic resilience of regions under crises: a study of the Australian economy

Courvisanos J., Jain A. and Mardaneh K. Economic resilience of regions under crises: a study of the Australian economy, Regional Studies. Identifying patterns of economic resilience in regions by industry categories is the focus of this paper. Patterns emerge from adaptive capacity in four distinct functional groups of local government regions in Australia, in respect of their resilience from shocks on specific industries. A model of regional adaptive cycles around four sequential phases – reorganization, exploitation, conservation and release – is adopted as the framework for recognizing such patterns. A data-mining method utilizes a k-means algorithm to evaluate the impact of two major shocks – a 13-year drought and the Global Financial Crisis – on four functional groups of regions, using census data from 2001, 2006 and 2011.

A relação entre confiança interpessoal e compartilhamento de conhecimento tácito

Empresas de negócios, que são constantemente pressionados por inovação, têm na criação de conhecimento organizacional a base para a estratégia de sobrevivência. Muito desse conhecimento acumulado é tácito, encarnado em indivíduos e incorporado pela organização, e que é de difícil articulação. A necessária justificativa de um novo conhecimento torna a sua criação um processo muito frágil. Indivíduos podem sentir-se ameaçados em compartilhar insights, intuição, novas ideias, know-how, habilidades específicas, diante de devastadores mecanismos de controle social como ridículo, difamação e opróbrio, ou pela possibilidade de mau uso de um conhecimento útil e valioso. Por outro lado, com a criança logo ao nascer, e derivado do narcisismo primário, emerge a confiança básica que acompanha o indivíduo ao longo de sua existência, e que, portanto, pode levá-lo a compartilhar seus achados. Esta pesquisa, um ensaio teórico, explorou a relação entre a confiança e compartilhamento de conhecimento tácito nas organizações. Com abordagem multidisciplinar, aderente ao pensamento complexo, incorporou referenciais teóricos advindos de trabalhos de neo-schumpeterianos (Teoria Evolucionária), da sociologia e da psicologia. O percurso metodológico contemplou a busca de artigos em base de dados, leitura de resumos de artigos, busca de autores consagrados na literatura, consulta de autores referenciados nos artigos, leitura e análise de trabalhos selecionados. Mediante análise de conteúdo, que busca identificar o que está sendo dito a respeito do tema, foram criadas as seguintes categorias de análise: inovação, poder, teoria de criação de conhecimento organizacional e confiança humana. Cada uma dessas categorias compôs um capítulo desta dissertação. Embora a escassez de pesquisas empíricas relacionadas ao tema, a análise de conteúdo dos artigos examinados permitiram concluir que a confiança interpessoal mantém relação de poder simétrico entre indivíduos e assim é capaz de acessar o conhecimento tácito enraizado na mente de indivíduos. Dessa forma, com a pesquisa aqui apresentada, espera-se ter contribuído para a literatura e práticas organizacionais relacionadas à gestão de conhecimento. Por fim, foram relatadas limitações no trabalho e sugestões para futuras pesquisas.

Differential-Evolution-Based Optimization of the Dynamic Response for Parallel Operation of Inverters With No Controller Interconnection

In this paper, the use of differential evolution ( DE), a global search technique inspired by evolutionary theory, to find the parameters that are required to achieve optimum dynamic response of parallel operation of inverters with no interconnection among the controllers is proposed. Basically, in order to reach such a goal, the system is modeled in a certain way that the slopes of P-omega and Q-V curves are the parameters to be tuned. Such parameters, when properly tuned, result in system's eigenvalues located in positions that assure the system's stability and oscillation-free dynamic response with minimum settling time. This paper describes the modeling approach and provides an overview of the motivation for the optimization and a description of the DE technique. Simulation and experimental results are also presented, and they show the viability of the proposed method.

Microfungal 'Weeds' in the Leafcutter Ant Symbiosis

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)