Flamingos are born white, but they turn pink because of the food they eat; this is an example of how , a physical factor, can affect phenotypes

The phenotype is the visible physical or biochemical characteristic of an individual organism which is determined by both genetic factors (genotype) and environmental influences. There are many environmental factors and they include diet, climate, illness and stress. If environmental factors have a strong influence this means the phenotypic plasticity is high (capable to change).