Individuals in the
mollusk species Donax variabilis show diverse coloration and patterning in their phenotypes. The phenotype of an individual
organism is either its total physical appearance and constitution or a specific manifestation of a
trait, such as size, eye color, or
behavior that varies between individuals. Phenotype is determined to a large extent by
genotype and influenced by
environmental factors. Early
geneticists were able to trace inheritance patterns without any knowledge of
molecular biology.Photo credit:
Debivort