Tropicality and abjection: What do we really mean by “Neglected Tropical Diseases”?

Neglected tropical diseases are defined operationally as diseases that prevail in “tropical” regions and are under‐researched, under‐funded, and under‐treated compared with their disease burden. By analysing the adjectives “tropical” and “neglected,” I expose and interrogate the discourses within which the term “neglected tropical disease” derives its meaning. First, I argue that the term “tropical” conjures the notion of “tropicality,” a form of Othering which erroneously explains the disease‐prevalence of “tropical” regions by reference to environmental determinism, rather than colonialism and neocolonialism. Second, I examine the way in which this Othering enables the abjection of tropical regions and their peoples, leading to neglect. I recommend that the term “neglected tropical diseases” be more carefully contextualised within health scholarship, education, and policy.     

The nucleo-mitochondrial conflict in cytoplasmic male sterilities revisited

Cytoplasmic male sterility (CMS) in plants is a classical example of genomic conflict, opposing maternally-inherited cytoplasmic genes (mitochondrial genes in most cases), which induce male sterility, and nuclear genes, which restore male fertility. In natural populations, this type of sex control leads to gynodioecy, that is, the co-occurrence of female and hermaphroditic individuals within a population. According to theoretical models, two conditions may maintain male sterility in a natural population: (1) female advantage (female plants are reproductively more successful than hermaphrodites on account of their global seed production); (2) the counter-selection of nuclear fertility restorers when the corresponding male-sterility-inducing cytoplasm is lacking. In this review, we re-examine the model of nuclear-mitochondrial conflict in the light of recent experimental results from naturally occurring CMS, alloplasmic CMS (appearing after interspecific crosses resulting from the association of nuclear and cytoplasmic genomes from different species), and CMS plants obtained in the laboratory and carrying mitochondrial mutations. We raise new hypotheses and discuss experimental models that would take physiological interactions between cytoplasmic and nuclear genomes into account.     

A new group-selection model for the evolution of homosexuality

Abstract. Scientists have long puzzled over how homosexual orientation has evolved, given the assumed low relative fitness of homosexual individuals compared to heterosexual individuals. A number of theoretical models for the evolution of homosexuality have been postulated including balance polymorphism, "Fertile females", hypervariability of DNA sequences, kin selection, and "parental manipulation". In this paper, I propose a new group-selection model for the evolution of homosexuality which offers two advantages over existing models: (1) its non-assumption of genetic determinism, and (2) its lack of dependency on an inefficient altruism relation and family dynamics theory.     

Comparison of isogenic lines provides evidence that phenotypic plasticity is under genetic control in rainbow trout Oncorhynchus mykiss

Comparison of nine isogenic lines of rainbow trout Oncorhynchus mykiss kept in the same environment showed significant genetic determinism of phenotypic plasticity assessed through body mass measurements. Ranking of lines differed between two tested environments.     

Evidence for determinism in species diversification and contingency in phenotypic evolution during adaptive radiation

Adaptive radiation (AR) theory predicts that groups sharing the same source of ecological opportunity (EO) will experience deterministic species diversification and morphological evolution. Thus, deterministic ecological and morphological evolution should be correlated with deterministic patterns in the tempo and mode of speciation for groups in similar habitats and time periods. We test this hypothesis using well-sampled phylogenies of four squamate groups that colonized the New World (NW) in the Late Oligocene. We use both standard and coalescent models to assess species diversification, as well as likelihood models to examine morphological evolution. All squamate groups show similar early pulses of speciation, as well as diversity-dependent ecological limits on clade size at a continental scale. In contrast, processes of morphological evolution are not easily predictable and do not show similar pulses of early and rapid change. Patterns of morphological and species diversification thus appear uncoupled across these groups. This indicates that the processes that drive diversification and disparification are not mechanistically linked, even among similar groups of taxa experiencing the same sources of EO. It also suggests that processes of phenotypic diversification cannot be predicted solely from the existence of an AR or knowledge of the process of diversification.     

Natural selection drives patterns of lake-stream divergence in stickleback foraging morphology

To what extent are patterns of biological diversification determined by natural selection? We addressed this question by exploring divergence in foraging morphology of threespine stickleback fish inhabiting lake and stream habitats within eight independent watersheds. We found that lake fish generally displayed more developed gill structures and had more streamlined bodies than did stream fish. Diet analysis revealed that these morphological differences were associated with limnetic vs. benthic foraging modes, and that the extent of morphological divergence within watersheds reflected differences in prey resources utilized by lake and stream fish. We also found that patterns of divergence were unrelated to patterns of phenotypic trait (co)variance within populations (i.e. the ‘line of least resistance’). Instead, phenotypic (co)variances were more likely to have been shaped by adaptation to lake vs. stream habitats. Our study thus implicates natural selection as a strong deterministic force driving morphological diversification in lake–stream stickleback. The strength of this inference was obtained by complementing a standard analysis of parallel divergence in means between discrete habitat categories (lake vs. stream) with quantitative estimates of selective forces and information on trait (co)variances.     

Review of genes in development: re-reading the molecular paradigm

Genes in Development is a collection of 13 stimulating essays on "post genomic" approaches to the concept of the gene. At the risk of caricaturing some complex balances, the contributors tend to be skeptical about genetic determinism, the central dogma of molecular biology, reductionism, genes as programs and the concept of the gene as a DNA sequence. They tend to like emergent properties, complexity theory, the parity thesis for developmental resources, developmental systems theory, and membranes. But within this broad weltanschauung the essays in Genes in Development vary widely in their interests and emphases––from the history of twentieth century genetics to the social and ethical issues raised by contemporary genetics––which makes for an attractive and valuable collection.     

RQA在肌电分析中的应用

介绍了递归图的生成方法和定量递归分析（RQA）中递归点的百发数,确定性线段的百分数,线段分布香农熵等分析量的意义。应用RQA分析肱二头肌及肱桡肌在不同负重下的肌电信号,发现肽二头肌肌电信号的递归点百分数的比肱肌高,有较强的周期性嵌入。与同一信号所作的FFT谱分析相比较,RQA法有较同的区分灵敏性,是肌电分析的一种新方法,它在其他复杂的生理信号处理中也有十分广阔的应用前景。     

Global patterns in the shape of species geographical ranges reveal range determinants

Aim Do species range shapes follow general patterns? If so, what mechanisms underlie those patterns? We show for 11,582 species from a variety of taxa across the world that most species have similar latitudinal and longitudinal ranges. We then seek to disentangle the roles of climate, extrinsic dispersal limitation (e.g. barriers) and intrinsic dispersal limitation (reflecting a species’ ability to disperse) as constraints of species range shape. We also assess the relationship between range size and shape. Location Global. Methods Range shape patterns were measured as the slope of the regression of latitudinal species ranges against longitudinal ranges for each taxon and continent, and as the coefficient of determination measuring the degree of scattering of species ranges from the 1:1 line (i.e. latitudinal range = longitudinal range). Two major competing hypotheses explaining species distributions (i.e. dispersal or climatic determinism) were explored. To this end, we compared the observed slopes and coefficients of determination with those predicted by a climatic null model that estimates the potential range shapes in the absence of dispersal limitation. The predictions compared were that species distribution shapes are determined purely by (1) intrinsic dispersal limitation, (2) extrinsic dispersal limitations such as topographic barriers, and (3) climate. Results  Using this methodology, we show for a wide variety of taxa across the globe that species generally have very similar latitudinal and longitudinal ranges. However, neither neutral models assuming random but spatially constrained dispersal, nor models assuming climatic control of species distributions describe range shapes adequately. The empirical relationship between the latitudinal and longitudinal ranges of species falls between the predictions of these competing models. Main conclusions We propose that this pattern arises from the combined effect of macroclimate and intrinsic dispersal limitation, the latter being the major determinant among restricted‐range species. Hence, accurately projecting the impact of climate change onto species ranges will require a solid understanding of how climate and dispersal jointly control species ranges.