Ecological-economic optimization of biodiversity conservation under climate change

Substantial investment in climate change research has led to dire predictions of the impacts and risks to biodiversity. The Intergovernmental Panel on Climate Change fourth assessment report(1) cites 28,586 studies demonstrating significant biological changes in terrestrial systems(2). Already high extinction rates, driven primarily by habitat loss, are predicted to increase under climate change(3-6). Yet there is little specific advice or precedent in the literature to guide climate adaptation investment for conserving biodiversity within realistic economic constraints(7). Here we present a systematic ecological and economic analysis of a climate adaptation problem in one of the world's most species-rich and threatened ecosystems: the South African fynbos. We discover a counterintuitive optimal investment strategy that switches twice between options as the available adaptation budget increases. We demonstrate that optimal investment is nonlinearly dependent on available resources, making the choice of how much to invest as important as determining where to invest and what actions to take. Our study emphasizes the importance of a sound analytical framework for prioritizing adaptation investments(4). Integrating ecological predictions in an economic decision framework will help support complex choices between adaptation options under severe uncertainty. Our prioritization method can be applied at any scale to minimize species loss and to evaluate the robustness of decisions to uncertainty about key assumptions.

Case studies and mathematical models of ecological speciation. 1. Cichlids in a crater lake.

A recent study of a pair of sympatric species of cichlids in Lake Apoyo in Nicaragua is viewed as providing probably one of the most convincing examples of sympatric speciation to date. Here, we describe and study a stochastic, individual-based, explicit genetic model tailored for this cichlid system. Our results show that relatively rapid (<20,000 generations) colonization of a new ecological niche and (sympatric or parapatric) speciation via local adaptation and divergence in habitat and mating preferences are theoretically plausible if: (i) the number of loci underlying the traits controlling local adaptation, and habitat and mating preferences is small; (ii) the strength of selection for local adaptation is intermediate; (iii) the carrying capacity of the population is intermediate; and (iv) the effects of the loci influencing nonrandom mating are strong. We discuss patterns and timescales of ecological speciation identified by our model, and we highlight important parameters and features that need to be studied empirically to provide information that can be used to improve the biological realism and power of mathematical models of ecological speciation.

Construct validity and internal reliability of a French version of FACES III in adolescents and adults

Family cohesion and adaptability, as operationalised in the Family Adaptability and Cohesion Scales III (FACES III), are two hypothesised dimensions of family functioning. We tested the properties of a French version of FACES III in school-children (mean age: 13 years; S.D:0.85) recruited from the general population and their parents. Separate confirmatory factor analyses were performed for adolescents and adults. The results of both analyses were compatible with a two-factor structure similar to that proposed by the authors of the original instrument. However, orthogonality between the two factors was only supported in the adult data. Internal reliability estimates were 0.78 and 0.68 in adolescents and 0.82 and 0.65 in adults, for cohesion and adaptability respectively.

Behavioural types and ecological effects in a natural population of the cooperative cichlid Neolamprologus pulcher

The ecological relevance of behavioural syndromes is little studied in cooperative breeding systems where it is assumed that the behavioural type might influence individual decisions on helping and dispersal (e.g. shy, nonaggressive and nonexplorative individuals remain philopatric and helpful, whereas bold, aggressive, explorative individuals compete for vacancies outside their group and disperse). We measured the behavioural type of 19 subordinates in the cooperatively breeding cichlid fish Neolamprologus pulcher in their natural environment by quantifying six behavioural traits up to four times ('trials') in three different contexts, by presenting them with a conspecific intruder, a predator or nothing inside a tube. We found only moderate within-context repeatability (intraclass correlation coefficients) of the focal individual's behaviour, except for attacking either the conspecific or the predator inside the tube. The focal individual's attack rate of the tube was also positively affected by its group size. Averaging traits per context removed the between-trial variation, and consequently the across-context repeatability was very high for all six traits, except for territory maintenance. Trait values depended significantly on the context, except for territory defence. Consequently, individuals could be classified into different behavioural types based on their reaction towards the tube, but surprisingly, and opposite to laboratory studies in this species, ranging propensity and territory maintenance were not included in this behavioural syndrome. We suggest that more studies are needed to compare standardized focal personality tests (e.g. exploration propensity) with actual behaviour observed in nature (e.g. ranging and dispersal).

Reproducibility and relative validity of a food-frequency questionnaire for French-speaking Swiss adults.

BACKGROUND: Due to the distinct cultural and language differences that exist in Switzerland, there is little information on the dietary intake among the general Swiss population. Adequately assessing dietary intake is thus paramount if nutritional epidemiological studies are to be conducted. OBJECTIVE: To assess the reproducibility and validity of a food-frequency questionnaire (FFQ) developed for French-speaking Swiss adults. DESIGN: A total of 23 men and 17 women (43.1+/-2.0 years) filled out one FFQ and completed one 24-hour dietary recall at baseline and 1 month afterward. RESULTS: Crude Pearson's correlation coefficients between the first and the second FFQ ranged from 0.58 to 0.90, intraclass correlation coefficient (ICC) ranged between 0.53 and 0.92. Lin's concordance coefficients ranged between 0.55 and 0.87. Over 80% of participants were classified in the same or adjacent tertile using each FFQ. Macronutrient intakes estimated by both FFQs were significantly higher than those estimated from the 24-hour recall for protein and water, while no significant differences were found for energy, carbohydrate, fats (five groups), and alcohol. De-attenuated Pearson's correlation coefficients between the 24-hour recall and the first FFQ ranged between 0.31 and 0.49, while for the second FFQ the values ranged between 0.38 and 0.59. Over 40 and 95% of participants fell into the same or the adjacent energy and nutrient tertiles, respectively, using the FFQs and the 24-hour recall. CONCLUSIONS: This FFQ shows good reproducibility and can be used determining macronutrient intake in a French-speaking Swiss population in an epidemiological setting.

Detecting and measuring deprivation in primary care: development, validity and reliability of a self-reported questionnaire - the DiPCare-Q

Background: General practitioners play a central role in taking deprivation into consideration when caring for patients in primary care. Validated questions to identify deprivation in primary-care practices are still lacking. For both clinical and research purposes, this study therefore aims to develop and validate a standardized instrument measuring both material and social deprivation at an individual level. Methods: The Deprivation in Primary Care Questionnaire (DiPCare-Q) was developed using qualitative and quantitative approaches between 2008 and 2011. A systematic review identified 199 questions related to deprivation. Using judgmental item quality, these were reduced to 38 questions. Two focus groups (primary-care physicians, and primary-care researchers), structured interviews (10 laymen), and think aloud interviews (eight cleaning staff) assured face validity. Item response theory analysis was then used to derive the DiPCare-Q index using data obtained from a random sample of 200 patients who were to complete the questionnaire a second time over the phone. For construct and criterion validity, the final 16 questions were administered to a random sample of 1,898 patients attending one of 47 different private primary-care practices in western Switzerland (validation set) along with questions on subjective social status (subjective SES ladder), education, source of income, welfare status, and subjective poverty. Results: Deprivation was defined in three distinct dimensions (table); material deprivation (eight items), social deprivation (five items) and health deprivation (three items). Item consistency was high in both the derivation (KR20 = 0.827) and the validation set (KR20 = 0.778). The DiPCare-Q index was reliable (ICC = 0.847). For construct validity, we showed the DiPCare-Q index to be correlated to patients' estimation of their position on the subjective SES ladder (rs = 0.539). This position was correlated to both material and social deprivation independently suggesting two separate mechanisms enhancing the feeling of deprivation. Conclusion: The DiPCare-Q is a rapid, reliable and validated instrument useful for measuring both material and social deprivation in primary care. Questions from the DiPCare-Q are easy to use when investigating patients' social history and could improve clinicians' ability to detect underlying social distress related to deprivation.

Evolutionary and ecological significance of non-shivering thermogenesis in the common vole

La production endogène à long terme de chaleur, même au repos, est une adaptation que l'on retrouve chez les animaux à sang chaud (les oiseaux et les mammifères). Cette production de chaleur a comme but le maintien d'une température constante du corps indépendamment de la température extérieure. A cette fin, les mammifères ont développé une forme de tissu spécialisé nommé tissu adipeux brun (BAT). Ce tissu est responsable de la conversion de nourriture en chaleur, procédé appelé thermogenèse sans frisson (NST = non-shivering thermogenesis). Durant ce procédé la uncoupling protein 1 (UCP1) convertit, au sein des mitochondries, la nourriture en chaleur au lieu de produire de l'ATP, molécule utilisée comme énergie cellulaire. On suppose que cette inefficacité de la conversion de la nourriture en ATP dans le BAT influence l'homéostasie de l'énergie, l'allocation des ressources ainsi que la régulation de processus gourmant en énergie comme la croissance et la reproduction. Afin de maintenir une température du corps constante, les mammifères doivent ajuster leur NST en fonction de la température ambiante. La NST devrait être donc plus importante que la croissance et la reproduction durant l'hiver que lors l'été/à haute altitude qu'à basse altitude. En effet, plusieurs études ont déjà démontré la dépendance de la NST aux divers paramètres environnementaux. Par contre, l'héritabilité de la NST ainsi que sa relation avec d'autres traits de caractère, ne sont que très peu connus, ceci malgré l'importance d'une telle information afin de pouvoir comprendre son potentiel évolutif. L'étude de l'importance évolutive et écologique sur la NST chez les campagnols des champs (Microtus arvalis) fut donc le but cette thèse de doctorat. Grâce aux informations collectées sur 4 générations de campagnols (chapitre 1), une dépendance saisonnière et journalière de la NST a été démontrée: elle augmente lors des périodes froides et diminue lors de la lactation. On a démontré que bien qu'étant plastique, la variation de la NST a une composante génétique significative. Elle est corrélée avec le taux d'activité métabolique au repos indiquant des contraintes intrinsèques. A l'aide d'une expérience de jardin commune, on a pu démontrer dans le chapitre 2 que les campagnols habitant en altitude ont une capacité génétique de thermogenèse sans frisson plus haute que celles de basse altitude. Ils produisent des portées plus petites et leur descendance grandit moins vite, surtout à partir du 10ème jour ce qui coïncide avec le début de la production de chaleur endogène. En choisissant artificiellement des campagnols avec une NST faible ou grande, on a pu démontrer une relation entre la NST et la développement de la masse corporelle. Les campagnols avec une haute NST grandissent plus lentement et sont plus légères à l'âge adulte que celles ayant une basse NST. A l'aide d'un croisement interligne entre les campagnols sélectionnés (avec basse et haute NST), on a pu montrer dans le chapitre 3 des effets « parent-of-origin >> du développement massique de la descendance, indiquant une empreinte génétique parentale. Cela veut dire que l'expression d'un allele dépend de l'origine parentale. De plus, des effets « parent-of-origin » des taux de base de norépinephrine et d'irisine ont pu être trouvés. Ces hormones sont connues pour influencer non seulement la TSF mais aussi d'autres caractéristiques. Ces influences ouvrent la voie à de nouvelles études sur la relation entre la TSF et l'histoire de vie. Dans le chapitre 4 on a démontré des effets à long terme de l'allocation des ressources en manipulant la taille des portées qui ont abouti à des différences dans l'investissement dans la reproduction et de la croissance de la descendance à la fois dans le cas de la reproduction manipulé et aussi dans le non - manipulée entre les femelles avec portées agrandies et réduites. Ensemble, ces résultats mettent en évidence le rôle central de la NST dans l'allocation des ressources sur la base d'un compromis entre le maintien et la croissance et ainsi transforme l'histoire de vie des mammifères. Ces études montrent comment les mammifères peuvent répondre rapidement à court et à long terme (c'est-à-dire par des réponses génétiques ou plastiques) à un changement rapide du climat. On montre aussi qu'il y a probablement une corrélation entre l'histoire de vie et des changements du comportement. Finalement mes résultats ont montré un lien étroit entre la NST et la croissance et les dimensions du corps. Ces résultats indiquent que le tissu adipeux brun et la NST pourraient être une cible thérapeutique intéressante pour traiter l'obésité.

Symbiotic effectiveness and ecological characterization of indigenous Rhizobium loti populations in Uruguay

The objectives of this work were to describe the distribution, density and seasonal variation of the indigenous populations of Rhizobium loti in different Uruguayan soils and to determine the symbiotic effectiveness and stress tolerance factors of different isolates, both with the aim of obtaining selected strains to re-introduce as inoculants in Lotus pastures. R. loti was present in ten soils studied and their densities varied from year to year and within each soil. All the isolates nodulated Lotus corniculatus effectively. The nodules in Lotus pedunculatus and Lotus subbiflorus were small, red on the surface and ineffective in nitrogen fixation. The study of 50 isolates from the ten soils showed high variability in their symbiotic efficiency and tolerance to pH. The indigenous population was acid tolerant in culture medium (pH 4.5), 83% of them could grow at pH 4.5 in 3 days. This work showed that there was a great diversity between the strains of R. loti isolated from Uruguayan soils and supports the importance of selecting among them the most efficient and resistant strains to be included in the inoculants.

Looking for Validity or Testing It? The Perils of Stepwise Regression, Extreme-Scores Analysis, Heteroscedasticity, and Measurement Error

When researchers introduce a new test they have to demonstrate that it is valid, using unbiased designs and suitable statistical procedures. In this article we use Monte Carlo analyses to highlight how incorrect statistical procedures (i.e., stepwise regression, extreme scores analyses) or ignoring regression assumptions (e.g., heteroscedasticity) contribute to wrong validity estimates. Beyond these demonstrations, and as an example, we re-examined the results reported by Warwick, Nettelbeck, and Ward (2010) concerning the validity of the Ability Emotional Intelligence Measure (AEIM). Warwick et al. used the wrong statistical procedures to conclude that the AEIM was incrementally valid beyond intelligence and personality traits in predicting various outcomes. In our re-analysis, we found that the reliability-corrected multiple correlation of their measures with personality and intelligence was up to .69. Using robust statistical procedures and appropriate controls, we also found that the AEIM did not predict incremental variance in GPA, stress, loneliness, or well-being, demonstrating the importance for testing validity instead of looking for it.

The family alliance assessment scales : steps toward validity and reliability of an observational assessment tool for early family interactions

We present the first steps in the validation of an observational tool for father-mother-infant interactions: the FAAS (Family Alliance Assessment Scales). Family-level variables are acknowledged as unique contributors to the understanding of the socio-affective development of the child, yet producing reliable assessments of family-level interactions poses a methodological challenge. There is, therefore, a clear need for a validated and clinically relevant tool. This validation study has been carried out on three samples: one non-referred sample, of families taking part in a study on the transition to parenthood (normative sample; n = 30), one referred for medically assisted procreation (infertility sample; n = 30) and one referred for a psychiatric condition in one parent (clinical sample; n = 15). Results show that the FAAS scales have (1) good inter-rater reliability and (2) good validity, as assessed through known-group validity by comparing the three samples and through concurrent validity by checking family interactions against parents' self-reported marital satisfaction.