Stressful conditions may cause plant cells to invest more energy in metabolic regulation and elimination of toxins and therefore to invest less energy in stabilizing symmetrical development, resulting in an increase in developmental noise
(M0ller and Swaddle, 1997; Leung et al.
DI is defined as a suite of processes that tend to disrupt the precise development of bilateral traits in organisms and is believed to stem from various exogenous and endogenous stresses that collectively referred to as developmental noise
or perturbations [3,4].
Objective: How robust phenotypes evolve despite developmental noise
First, it measures minor genetically and environmentally induced departures from a perfectly designed developmental programme, and thus is provides a gauge of the organism's developmental noise
, and indirectly of its viability fitness.
The residual of the environmental variance would then result from developmental noise and/or diverse non-Mendelian parental (maternal) effects.
Developmental noise, phenotypic plasticity, and allozyme heterozygosity in Daphnia.
It would appear illogical to expect the genetic mechanisms responsible for developmental stability to differ between the sexes given that both males and females need to be able to regulate and buffer character development against developmental noise
and environmental perturbation.
Since the same genes code for proteins in each half of symmetrical traits, differences between halves is a measure of developmental noise
, and the organism's inability to correct for developmental noise
, or developmental instability (Mather 1953, Soule 1979, Parsons 1991, Palmer 1996).
Palmer (1994) Palmer and Strobeck (1992) assert that distributions of asymmetries within a population that do not meet these criteria may represent the effects of factors other than developmental noise
and developmental stability, such as genetic predisposition (e.