∞ generated and posted on 2016.12.24 ∞
Phenotypic variation on a character.
An example of a character would be eye color whereas an example of a trait would be blue eyes, or brown eyes, etc. That is, the difference between a character and a trait is essentially the difference between a broader category of things and a more specific description of a specific thing. Another illustration, but not from biology: counting numbers (character equivalent) and the number 6 (trait equivalent). See also the concept of quantitative traits.
To some extent genetic variation – that is, variation in genotype – underlies phenotypic variation. In fact, one can go further and find important parallels between the idea of genes and that of characters versus the idea of alleles (which gene variants) and traits (which are character variants). This match up isn't perfect, however, since different alleles can result in equivalent traits, which is a variation on the idea of neutral variation.
Alternatively, the impact of the environment on phenotypes can obscure allele-trait relationships. Such phenotypic variation that occurs despite genotypic constancy may be expressed in the concepts of penetrance or phenotypic plasticity. Another way to make these points are that there are certain "rules" underlying how one goes from genotype information to phenotype information (i.e., allele-trait associations) but that these rules do not necessarily always perfectly hold.