Any change that occurs in the body of an organisms in response to changing environmental conditions is termed as Phenotypic adaptation. It includes non-genetic changes in individuals such as physiological modification, acclimatization or behavioural changes to escape or adapt to the environmental conditions.

Examples:

i. Kangaroo rat: Internal fat oxidation occurs to produce water as by product, which helps it to survive in desert conditions.

ii. Desert plants: Thick cuticle, stomata in deep to minimize transpiration

iii. Cold climate Mammals: short ears and limbs to minimize heat loss.

iv. People at high altitude: increased R.B.C production and increased breathing rate.

v. Desert lizards: bask in sun when cold and move to shade when hot.