Heritability and genetic correlations of escape behaviours in juvenile scallop Argopecten purpuratus.
Brokordt, K., Farías, W., Lhorente, J., & Winkler, F.
Escape behaviours are generally considered adaptive because of their obvious effects on fitness. However, little is known about the genetic basis of escape responses. The estimation of the magnitude of hereditary factors affecting variation in escape responses indicates their potential to evolve by natural selection. Scallops are exceptional among bivalve molluscs because they possess an excellent swimming capacity, which helps them to escape predators. In this study we estimated the narrow-sense heritability (h2), phenotypic variance components and phenotypic and genetic correlations of several escape response traits (i.e. reaction time, number of claps (rapid valve closures and openings), and the duration and intensity of the clapping response) in juvenile Argopecten purpuratus scallops. We stimulated scallop escape responses using their natural predator, the sea star Meyenaster gelatinosus. Genetic estimates for escape response traits were determined by the animal model. Most studied traits showed substantial amounts of additive genetic variance controlling their phenotypic variation (CVA = 18.43–100.2), were repeatable (at least over a short period, R = 0.36–0.42), and had significant heritabilities (h2 = 0.36–0.57). Indeed, it can be inferred that most of the analysed escape response traits of A. purpuratus could evolve through natural selection. Moreover, significant genetic correlations between some escape response traits were observed, suggesting that selection acting on one escape trait will affect that of another, facilitating their coevolution.
Palabras claves: Argopecten purpuratus; escape behaviour; genetic correlation; heritability; scallop
Referencia APA: Brokordt, K., Farías, W., Lhorente, J., & Winkler, F. (2012). Heritability and genetic correlations of escape behaviours in juvenile scallop Argopecten purpuratus. Animal Behaviour, 84(2), 479-484.
What do we know about high-altitude precipitation in the semi-arid Andes of Chile?
Bourgin P, Andreassian V, Gascoin S, Valery A.
Mapping precipitations on a regular grid is often required for hydrological and ecological modelling. The spatial interpolation methods are generally used to estimate such a distribution from ground-based measurements. In the case of mountainous areas, the estimation of precipitation amounts is still a challenging task and the results of spatial interpolation should be verified as much as possible. Here we describe a three-steps method for the validation of a precipitation map. This is used in the context of a mountainous semi-arid region, the Norte Chico in Chile (26°S-32°S). The implementation of this validation method showed the benefits of an interpolation method developed by Valéry  for mountainous areas. The hydrological balance of the high-altitude watersheds is now more realistic.
Palabras claves: Precipitation, spatial interpolation method, extrapolation, altitude, altitudinal corrections, validation, water equivalent, water balance.
Referencia APA: Bourgin P, Andreassian V, Gascoin S, Valery A. (2012). Que sait-on des précipitations en altitude dans les Andes semi-arides du Chili?. La Houille Blanche. 2012;(2):12-17.