RESUMO
The measurement tool most used to estimate developmental stability (DS) is fluctuating asymmetry (FA), which is a measure of the small random deviations that occur between the left and right sides of bilaterally symmetrical traits. In the Biobío Region of Chile, forest plantations are a widely extended phenomenon, which affect 27% of the surface area of the region and which are dominated by the monoculture of Pinus radiata. This study evaluated the presence of FA in the body shape of two populations of Ceroglossus chilensis (Eschscholtz) in two 13-year-old forest plantations (commercial thinning) using insects collected with interception traps. Since the biotic and abiotic components of forest plantations are subject to continual anthropic modifications that affect almost all ecological processes, including population dynamics, community composition, and material and energy flows, these characteristics are reflected in the DS of individuals. The results showed that there was greater precision using geometric morphometrics to detect the presence of asymmetry in plantations due to shape analysis, as proposed by studies in antennal morphology using traditional measures. It should be noted that the populations were exposed to different environments; the population in the Coast Range is more humid, while the Andes Foothills population is in a drier area with drier soils. In spite of this, there was minimum phenotypic variation detected at the population level, which reflected the different environments and may be associated with patterns of environmental phenotypic plasticity.
Assuntos
Besouros/anatomia & histologia , Caracteres Sexuais , Animais , Feminino , Masculino , ÁrvoresRESUMO
Phenological studies are especially important in order to understand the ecological process operating at temporal level. The western slopes of the northern Chilean Andes at about 3,500 m asl are a mosaic of arid environments in which precipitations are highly seasonal, mostly concentrated in summer. Teriocolias zelia andina Forbes (Lepidoptera: Pieridae) is one of the most conspicuous and regularly observed butterflies flying in this region; it is a host specialist associated with the native shrub Senna birostris var. arequipensis (Fabaceae). The objectives of this study were (1) to characterize the temporal variations in the relative abundance of eggs of this host-specialist butterfly and (2) to examine the relationship of these variations with leaf phenology. Monthly samplings of eggs were carried out from February 2011 to January 2012. Circular statistical analyses of the relative abundance of eggs indicated clustered distribution along the year with the mean vector in June. Temporal variation in the relative abundance of eggs was correlated (Spearman rank correlation test) with the availability of plant substrate for egg laying and larval feeding.