ABSTRACT
T.N. Ananthakrishnan Flat No. 6, Dwarka, 42 (Old No. 22), Kamdar Nagar, Nungambakkam, Chennai 600034, India; e-mail: ananththrips@yahoo.com
Introduction
All species exhibit phenotypic variation. In some cases, this variation is directly controlled by underlying genetic variation, whereas in other cases, variation in phenotype is induced by the environment. The latter case is termed phenotypic plasticity, and is defined here as the expression of different phenotypes in a single genotype when subjected to different environments. Phenotypic plasticity is a complicated subject that has recently received a tremendous amount of attention, largely because of the realization that phenotypic plasticity is ubiquitous, and is important for understanding the ecology, taxonomy, and evolution of populations and species (Scheiner 1993, Nylin and Gotthard 1998, Schlichting and Pigliucci 1998, Pigliucci 1996, 2001, Agrawal 2001, West-Eberhard 2003). A knowledge of the patterns of such plasticities and an assessment of their implication are useful in the proper assessment of species.
