Genetic and environmental effects on early life-history traits in salmonids

Les changements environnementaux, tels la température ou les maladies infectieuses, peuvent influencer l'évolution en induisant de la sélection, mais ceci à la seule condition qu'il y ait assez de diversité génétique pour les traits en question ou pour l'expression plastique de ces traits. Au cours cette thèse, nous avons étudié l'effet de potentielles pressions environnementales sur différents phénotypes de trois représentants des sous familles des salmonidés: l'ombre commun (Thymallus thymallus; Thymallinae), la truite de rivière {Salmo trutta; Salmoninae) et le corégone Coregonus palaea (Coregoninae). Les salmonidés se prêtent particulièrement bien à ce type d'expériences car étant hautement sensibles aux conditions environnementales, ils montrent une large variabilité dans leurs traits morphologiques, comportementaux ainsi que d'histoire de vie, tout en bénéficiant d'un large intérêt général. Nous avons testé si le sexe de l'ombre commun pouvait être modifié par la température, ce qui pourrait ainsi expliquer un changement abrupte de sex ratio observé dans l'une des plus grandes populations de Suisse. Nous n'avons trouvé aucun indice permettant de conclure que la température puisse induire ce changement chez l'ombre commun ou chez la truite de rivière. De plus nous avons étudié la plasticité de développement ainsi que d'éclosion, et avons observé des différences entre familles ainsi qu'entre populations. Alors que ces différences comportementales entre populations suggéraient une adaptation aux conditions environnementales locales, cette prédiction n'a pas été confirmée par une expérience de transplantation réciproque d'embryons entre cinq rivières de la même région. Cette étude a montré que les embryons ne survivaient pas mieux dans leur rivière d'origine, indiquant donc une absence d'adaptation locale. Nous avons aussi montré que la mortalité embryonnaire était influencée autant par des "bons gènes" que par des "gènes compatibles", que la qualité des mâles pouvait être signalée par leur coloration, et que le fait d'élever des poissons dans une pisciculture pouvait aboutir a des relations contre-intuitives entre la coloration des mâles et la qualité de leur jeunes. Nos résultats contribuent ainsi à une meilleure compréhension de l'effet de diverses pressions environnementales sur la morphologie, le comportement ou les traits d'histoire de vie chez les salmonidés. - Environmental changes, such as changes in temperatures or infection levels, can induce selection and drive evolution if there is sufficient genetic variation for the traits or the plasticity in trait expression. In this thesis, we investigated the influence of potential environmental stressors on various phenotypes in representatives of the three salmonid subfamilies: the European grayling (Thymallus thymallus; Thymallinae), the brown trout (,Salmo trutta; Salmoninae), and the whitefish Coregonus palaea (Coregoninae). Salmonids are ideal study species, as they seem sensitive to changing environmental conditions, show considerable variability in morphological, behavioral, and life history traits, and are of broad public interest. We investigated whether temperature-induced sex reversal could explain the sex-ratio distortion found in one of Switzerland's largest grayling populations. We found no evidence of temperature-induced sex reversal in either graylings or brown trout. We also examined plasticity in embryo development and the timing of hatching. We found variation at the level of family and population. Although behavioral differences between populations suggested adaptation to local environmental conditions, no indications of local adaptation could be found in reciprocal transplant experiments carried out over five rivers in the same region. We also demonstrate that embryo development and viability is influenced by 'good genes' and 'compatible genes', that the genetic quality of sires can be signaled by their grey coloration, and that raising larvae in a hatchery environment can produce counter-intuitive relationships between male phenotypes and offspring viability. Our results contribute to the understanding of how changing environmental conditions affect the phenotypes and the heritability of early life-history traits in salmonids.

Linking life-history traits, ecology, and niche breadth evolution in north american eriogonoids (polygonaceae).

Abstract Macroevolutionary and microevolutionary studies provide complementary explanations of the processes shaping the evolution of niche breadth. Macroevolutionary approaches scrutinize factors such as the temporal and spatial environmental heterogeneities that drive differentiation among species. Microevolutionary studies, in contrast, focus on the processes that affect intraspecific variability. We combine these perspectives by using macroevolutionary models in a comparative study of intraspecific variability. We address potential differences in rates of evolution of niche breadth and position in annual and perennial plants of the Eriogonoideae subfamily of the Polygonaceae. We anticipated higher rates of evolution in annuals than in perennials owing to differences in generation time that are paralleled by rates of molecular evolution. Instead, we found that perennial eriogonoid species present greater environmental tolerance (wider climate niche) than annual species. Niche breadth of perennial species has evolved two to four times faster than in annuals, while niche optimum has diversified more rapidly among annual species than among perennials. Niche breadth and average elevation of species are correlated. Moreover, niche breadth increases more rapidly with mean species elevation in perennials than in annuals. Our results suggest that both environmental gradients and life-history strategy influence rates and patterns of niche breadth evolution.

Genetic and environmental effects on the covariation betweencolour polymorphism and a life history trait

Variation in coloration with a strong underlying genetic basis is frequently found within animal populations but little is known about its function. Covariation between colour polymorphism and life-history traits can arise because morphs perform differently among environments or because they possess alternative alleles coding for key life-history traits. To test these two hypotheses, we studied a population of tawny owls Strix aluco, a bird displaying red, brown and grey morphs. We assessed the colour morph of breeding females, swapped eggs or hatchlings between pairs of nests, and examined how body condition in 3-week-old nestlings covaries with coloration of foster and genetic mothers. Redder foster and genetic mothers produced young in better condition. Because in two other years we observed that greyish females produced offspring in better condition than those of red females, the present study suggests that colour polymorphism signals genetic and phenotypic adaptations to cope with a fluctuating environment.

Life-history evolution and the polyphenic regulation of somatic maintenance and survival.

Here we discuss life-history evolution from the perspective of adaptive phenotypic plasticity, with a focus on polyphenisms for somatic maintenance and survival. Polyphenisms are adaptive discrete alternative phenotypes that develop in response to changes in the environment. We suggest that dauer larval diapause and its associated adult phenotypes in the nematode (Caenorhabditis elegans), reproductive dormancy in the fruit fly (Drosophila melanogaster) and other insects, and the worker castes of the honey bee (Apis mellifera) are examples of what may be viewed as the polyphenic regulation of somatic maintenance and survival. In these and other cases, the same genotype can--depending upon its environment--express either of two alternative sets of life-history phenotypes that differ markedly with respect to somatic maintenance, survival ability, and thus life span. This plastic modulation of somatic maintenance and survival has traditionally been underappreciated by researchers working on aging and life history. We review the current evidence for such adaptive life-history switches and their molecular regulation and suggest that they are caused by temporally and/or spatially varying, stressful environments that impose diversifying selection, thereby favoring the evolution of plasticity of somatic maintenance and survival under strong regulatory control. By considering somatic maintenance and survivorship from the perspective of adaptive life-history switches, we may gain novel insights into the mechanisms and evolution of aging.

How demography, life history, and kinship shape the evolution of genomic imprinting.

How phenomena like helping, dispersal, or the sex ratio evolve depends critically on demographic and life-history factors. One phenotype that is of particular interest to biologists is genomic imprinting, which results in parent-of-origin-specific gene expression and thus deviates from the predictions of Mendel's rules. The most prominent explanation for the evolution of genomic imprinting, the kinship theory, originally specified that multiple paternity can cause the evolution of imprinting when offspring affect maternal resource provisioning. Most models of the kinship theory do not detail how population subdivision, demography, and life history affect the evolution of imprinting. In this work, we embed the classic kinship theory within an island model of population structure and allow for diverse demographic and life-history features to affect the direction of selection on imprinting. We find that population structure does not change how multiple paternity affects the evolution of imprinting under the classic kinship theory. However, if the degree of multiple paternity is not too large, we find that sex-specific migration and survival and generation overlap are the primary factors determining which allele is silenced. This indicates that imprinting can evolve purely as a result of sex-related asymmetries in the demographic structure or life history of a species.

Prenatal Representations of Family in Parents and Coparental Interactions as Predictors of Triadic Interactions During Infancy

In this study, we explored the predictive role of family interactions and family representations in mothers and fathers during pregnancy for postnatal motherfatherinfant interactions during the first 2 years after birth. Families (N = 42) were seen at the fifth month of pregnancy and at 3 and 18 months after birth. During pregnancy, parents were asked to play with their baby at the first meeting by using a doll in accordance with the procedure of the prenatal Lausanne Trilogue Play (LTP; A. Corboz-Warnery & E. Fivaz-Depeursinge, 2001; E. Fivaz-Depeursinge, F. Frascarolo-Moutinot, & A. Corboz-Warnery, 2010). Family representations were assessed by administering the Family System Test (T. Gehring, 1998). Marital satisfaction and the history of the couple were assessed through self-reported questionnaires. At 3 and 18 months, family interactions were assessed in the postnatal LTP. Infant temperament was assessed through parent reports. Results show that (a) prenatal interactions and child temperament are the most important predictors of family interactions and (b) paternal representations are predictive of family interactions at 3 months. These results show that observational assessment of nascent family interactions is possible during pregnancy, which would allow early screening of family maladjustment. The findings also highlight the necessity of taking into account paternal representations as a significant variable in the development of family interactions.

Prevalence and factors associated with difficulty and intention to quit smoking in Switzerland.

ABSTRACT: BACKGROUND: Recent data indicate a slight decrease in the prevalence of smoking in Switzerland, but little is known regarding the intention and difficulty to quit smoking among current smokers. Hence, we aimed to quantify the difficulty and intention to quit smoking among current smokers in Switzerland. METHODS: Cross-sectional study including 607 female and 658 male smokers. Difficulty, intention and motivation to quit smoking were assessed by questionnaire. RESULTS: 90% of women and 85% of men reported being "very difficult" or "difficult" to quit smoking. Almost three quarters of smokers (73% of women and 71% of men) intended to quit; however, less than 20% of them were in the preparation stage and 40% were in the precontemplation stage. On multivariate analysis, difficulty to quit was lower among men (Odds ratio and 95% [confidence interval]: 0.51 [0.35-0.74]) and increased with nicotine dependence and number of previous quitting attempts (OR=3.14 [1.75-5.63] for 6+ attempts compared to none). Intention to quit decreased with increasing age (OR=0.48 [0.30-0.75] for [greater than or equal to]65 years compared to <45 years) and increased with nicotine dependence, the number of previous quitting attempts (OR=4.35 [2.76-6.83] for 6+ attempts compared to none) and among non-cigarette smokers (OR=0.51 [0.28-0.92]). Motivation to quit was inversely associated with nicotine dependence and positively associated with the number of previous quitting attempts and personal history of lung disease. CONCLUSION: Over two thirds of Swiss smokers want to quit. However, only a small fraction wishes to do so in the short term. Nicotine dependence, previous attempts to quit or previous history of lung disease are independently associated with difficulty and intention to quit.

Risk factors for head and neck cancer in young adults : a pooled analysis in the INHANCE consortium

BACKGROUND: Increasing incidence of head and neck cancer (HNC) in young adults has been reported. We aimed to compare the role of major risk factors and family history of cancer in HNC in young adults and older patients. METHODS: We pooled data from 25 case-control studies and conducted separate analyses for adults ≤45 years old ('young adults', 2010 cases and 4042 controls) and >45 years old ('older adults', 17 700 cases and 22 704 controls). Using logistic regression with studies treated as random effects, we estimated adjusted odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: The young group of cases had a higher proportion of oral tongue cancer (16.0% in women; 11.0% in men) and unspecified oral cavity / oropharynx cancer (16.2%; 11.1%) and a lower proportion of larynx cancer (12.1%; 16.6%) than older adult cases. The proportions of never smokers or never drinkers among female cases were higher than among male cases in both age groups. Positive associations with HNC and duration or pack-years of smoking and drinking were similar across age groups. However, the attributable fractions (AFs) for smoking and drinking were lower in young when compared with older adults (AFs for smoking in young women, older women, young men and older men, respectively, = 19.9% (95% CI = 9.8%, 27.9%), 48.9% (46.6%, 50.8%), 46.2% (38.5%, 52.5%), 64.3% (62.2%, 66.4%); AFs for drinking = 5.3% (-11.2%, 18.0%), 20.0% (14.5%, 25.0%), 21.5% (5.0%, 34.9%) and 50.4% (46.1%, 54.3%). A family history of early-onset cancer was associated with HNC risk in the young [OR = 2.27 (95% CI = 1.26, 4.10)], but not in the older adults [OR = 1.10 (0.91, 1.31)]. The attributable fraction for family history of early-onset cancer was 23.2% (8.60% to 31.4%) in young compared with 2.20% (-2.41%, 5.80%) in older adults. CONCLUSIONS: Differences in HNC aetiology according to age group may exist. The lower AF of cigarette smoking and alcohol drinking in young adults may be due to the reduced length of exposure due to the lower age. Other characteristics, such as those that are inherited, may play a more important role in HNC in young adults compared with older adults.

Sex, politics and social change in the eighteenth and the nineteenth centuries: Evidence from the Swiss Alps

The 18th century "sexual revolution" can not simply be explained as a consequence of economic or institutional factors - industrialization, agricultural revolution, secularization or legal hindrances to marriages: the example of western Valais (Switzerland) shows that we have to deal with a complex configuration of factors The micro-historical approach reveals that in the 18th and 19th century sexuality - and above all illicit sexuality - was a highly subversive force which was considerably linked to political innovation and probably more generally to historical change. Non-marital sexuality was clearly tied to political dissent ant to innovative ways of behaviour, both among the social elites and the common people. This behaviour patterns influenced crucial evolutions in the social, cultural and economic history of the region.

Variation in the intensity of inbreeding depression among successive life-cycle stages and generations in gynodioecious Silene vulgaris (Caryophyllaceae).

Inbreeding depression is one of the hypotheses explaining the maintenance of females within gynodioecious plant populations. However, the measurement of fitness components in selfed and outcrossed progeny depends on life-cycle stage and the history of inbreeding. Comparative data indicate that strong inbreeding depression is more likely to occur at later life-cycle stages. We used hermaphrodite individuals of Silene vulgaris originating from three populations located in different valleys in the Swiss Alps to investigate the effect of two generations of self- and cross-fertilization on fitness components among successive stages of the life cycle in a glasshouse experiment. We detected significant inbreeding depression for most life-cycle stages including: the number of viable and aborted seeds per fruit, probability of germination, above ground biomass, probability of flowering, number of flowers per plant, flower size and pollen viability. Overall, the intensity of inbreeding depression increased among successive stages of the life cycle and cumulative inbreeding depression was significantly stronger in the first generation (delta approximately 0.5) compared with the second generation (delta approximately 0.35). We found no evidence for synergistic epistasis in our experiment. Our finding of more intense inbreeding depression during later stages of the life cycle may help to explain the maintenance of females in gynodioecious populations of S. vulgaris because purging of genetic load is less likely to occur.

Prevalence, awareness, treatment and control of hypertension in a Swiss general population: the CoLaus Study

Objective: To assess the prevalence levels of awareness, treatment and control of hypertension and associated factors in Switzerland. Methods: Population-based cross-sectional study of 6,182 subjects (52.5% women) aged 35-75 years living in Lausanne, Switzerland. Hypertension was defined as blood pressure ≥140/90 mm Hg or current antihypertensive medication. Results: The overall prevalence of hypertension was 36% (95% CI: 35-38%). Among hypertensive participants, 63% were aware of having hypertension. Among aware hypertensives, 78% were treated, and among treated hypertensives 48% were controlled (BP <140/90 mmHg). In multivariate analysis, prevalence of hypertension was associated with older age, male gender, low educational level, high alcohol intake, awareness of diabetes, awareness of dyslipidaemia, obesity and parental history of myocardial infarction (MI). Awareness of hypertension was associated with older age, female gender, awareness of diabetes, awareness of dyslipidaemia, obesity and parental history of MI. Control was associated with younger age, higher educational level and no alcohol intake. Alone or in combination, sartans were the most often prescribed antihypertensive medication category (41%), followed by diuretics, beta-blockers, ACE inhibitors and calcium channel blockers. Only 31% of treated hypertensives were taking ≥2 antihypertensive medications. Conclusion: Although more than half of the participants with hypertension were aware of being hypertensive and more than three quarters of them received a pharmacological treatment, less than half of those treated were adequately controlled. Treated hypertensive subjects should be followed up more closely.

Stable isotope geochemistry and formation mechanisms of quartz veins; Extreme paleoaltitudes of the Central Alps in the Neogene

Quartz veins ranging in size from less than 50 cm length and 5 cm width to greater than 10 m in length and 5 m in width are found throughout the Central Swiss Alps. In some cases, the veins are completely filled with milky quartz, while in others, sometimes spectacular void-filling quartz crystals are found. The style of vein filling and size is controlled by host rock composition and deformation history. Temperatures of vein formation, estimated using stable isotope thermometry and mineral equilibria, cover a range of 450 degrees C down to 150 degrees C. Vein formation started at 18 to 20 Ma and continued for over 10 My. The oxygen isotope values of quartz veins range from 10 to 20 permil, and in almost all cases are equal to those of the hosting lithology. The strongly rock-buffered veins imply a low fluid/rock ratio and minimal fluid flow. In order to explain massive, nearly morromineralic quartz formation without exceptionally large fluid fluxes, a mechanism of differential pressure and silica diffusion, combined with pressure solution, is proposed for early vein formation. Fluid inclusions and hydrous minerals in late-formed veins have extremely low delta D values, consistent with meteoric water infiltration. The change from rock-buffered, static fluid to infiltration from above can be explained in terms of changes in the large-scale deformation style occurring between 20 and 15 Ma. The rapid cooling of the Central Alps identified in previous studies may be explained in part, by infiltration of cold meteoric waters along fracture systems down to depths of 10 km or more. An average water flux of 0.15 cm 3 cm(-2)yr(-1) entering the rock and reemerging heated by 40 degrees C is sufficient to cool rock at 10 km depth by 100 degrees C in 5 million years. The very negative delta D values of < -130 permil for the late stage fluids are well below the annual average values measured in meteoric water in the region today. The low fossil delta D values indicate that the Central Alps were at a higher elevation in the Neogene. Such a conclusion is supported by an earlier work, where a paleoaltitude of 5000 meters was proposed on the basis of large erratic boulders found at low elevations far from their origin.

The Irish Infancy Narratives and their Relationship with Latin Sources

(Résumé de l'ouvrage) In 1927 M. R. James published Latin Infancy Gospels, identified by him in two related but not identical manuscripts (one the British Library Arundel 404; the other from Hereford), together with a parallel text from the Irish manuscript known as the Leabhar Breac. Later researches brought to light more manuscripts of this Latin work, and also of the Irish text. James recognized that his apocryphal Latin Infancy text was compiled from a combination of the Protevangelium of James and a hitherto unknown text which he named "The Source". Recent research has identified a full Latin translation of the Protevangelium of James. A hitherto unrecognized Irish Infancy Narrative has also been identified in the Dublin manuscript known as the Liber Flavus Fergusiorum. A deep study of this related tradition was called for. This has been carried out over the past ten years by an Irish team in conjunction with Professor Daniel Kaestli and AELAC. The fruits of this labour are published in these two volumes. Volume 13 has a general introduction with a historical sketch of New Testament apocrypha in Ireland and a history of research on the subject. This is followed by a comparison of the Infancy Narratives in the Leabhar Breac and the Liber Flavus Fergusiorum. There are special introductions to these Infancy texts, followed by critical editions of the Irish texts, accompanied by English translations and rich annotation. Next there is similar treatment of the Irish versified Narrative (from ca. 700) of the Childhood Deeds of Jesus (commonly known as the Infancy Narrative (or Gospel) of Thomas. There is then (in volume 14, but with continuous pagination) the edition and translation of an Irish thirteenth-century poem with elements from Infancy Narratives, and both Latin and Irish texts on the wonders at Christ's birth, accompanied by translations and notes. The edition of the Irish material is followed by a critical edition of the full Arundel and Hereford forms of the Infancy Narrative (here referred to as the "J Compilation"), together with a detailed study of all the questions relating to this work. The volume concludes with a critical edition (by Rita Beyers) of the Latin text of the Protevangelium of James, accompanied by a detailed study of the work.. The work contains a detailed study of the Latin translations of the Protevangelium of James and the transmission of this work in the West. The "J Compilation" (a combination of the Protevangelium and texts of Pseudo-Matthew) can be traced back in manuscript transmission to ca. 800,and must have originated some time earlier. Behind it stands an earlier "I ("I" for Irish) Compilation" without influence from Pseudo-Matthew, the form found in the Irish witnesses. It is argued that M. R. James's "Source" may be of Judaeo-Christian origin and may really be the Gospel of the Nazoreans. Among the indexes there is a list of all the Irish words found in the texts. This edition of the Irish and related Latin texts is a major contribution to the study of the apocryphal Infancy Narratives. It should also be of particular interest to Celtic scholars, to students of Irish ecclesiastical learning, and in general to all medievalists.