2 resultados para Developmental stages
em University of Connecticut - USA
Resumo:
Family court judges are often asked to make inferences about - or directly interview children to ascertain - children's custody preferences and their maturity to express such preferences. These estimates of children's developmental maturity are important to the judges' considerations of children's "best interests" in custody cases. The research literature describing family court judges' background, education, training, and knowledge about child development is scant. With appropriate child development knowledge, judges should be better able to identify the developmental stages at which children have the cognitive and social capabilities to communicate directly their placement wishes or concerns. The current study is the first to examine judges' estimates of - and actual tests of - their child development knowledge, their training/education, and their application of this knowledge to their decisions to involve children as participants in contested custody cases.
Resumo:
The ability to respond plastically to the environment has allowed amphibians to evolve a response to spatial and temporal variation in predation threat (Benard 2004). Embroys exposed to egg predation are expected to hatch out earlier than their conspecifics. Larval predation can induce a suite of phenotypic changes including growing a larger tail area. When presented with cues from both egg and larval predators, embryos are expected to respond to the egg predator by hatching out earlier because the egg predator presents an immediate threat. However, hatching early may be costly in the larval environment in terms of development, morphology, and/or behavior. We created a laboratory experiment in which we exposed clutches of spotted salamander (Ambystoma maculatum) eggs to both egg (caddisfly larvae) and larval (A. opacum) predators to test this hypothesis. We recorded hatching time and stage and took developmental and morphological data of the animals a week after hatching. Larvae were entered into lethal predation trials with a larval predatory sunfish (Lepomis sp.) in order to study behavior. We found that animals exposed to the egg predator cues hatched out earlier and at earlier developmental stages than conspecifics regardless of whether there was a larval predator present. Animals exposed to larval predator cues grew relatively larger tails and survived longer in the lethal predation trials. However the group exposed to both predators showed a cost of early hatching in terms of lower tail area and shorter survival time in predation trials. The morphological and developmental effects measured of hatching plasticity were transient as there were no developmental or morphological differences between the treatment groups at metamorphosis. Hatching plasticity may be transient but it is important to the development and survival of many amphibians.