Phenotypic plasticity refers to the ability of an organism to change its physical traits in response to environmental cues. Synonyms for this concept include trait flexibility, environmental responsiveness, and morphological adaptability. Additionally, the term developmental plasticity is often used when describing the ability of an organism's early life experiences to affect its later physical characteristics. Evolutionary biologists may use the term phenotypic variation to describe the range of possible physical traits that a population can display due to plasticity. These synonyms all point to the same idea, that an organism's physical traits are not fixed and can change in response to the environment.