The Lady in the Lab

Phenotypic characters are not only an expression of inherited genes, rather they are influenced by environmental factors as well. Environmental factors that influence phenotypic expression can be temperature, diet, and presence of predators. I - Phenotypic plasticity Phenotypic plasticity is the ability of an organism to react to an environmental input with a change in form, state, movement, or rate of activity. There are two main types of phenotypic plasticity: reaction norm and polyphemism. A. Reaction norm In reaction norm, the genome encodes a range of potential phenotypes, and the environment that the individual is exposed to determines what phenotype should be expressed.  B. Polyphemism The genome only encodes for the phenotype that would best suit the organism in the environment it is in. The environmental factors that usually influences the organism's phenotype are temperature, diet, and presence of predator. 1. Temperature-induced polyphemism ...