Characteristics or features developed during an individual’s lifetime, through experience or environmental influences, represent changes not encoded within the organism’s DNA. For instance, increased muscle mass resulting from weightlifting or a scar acquired from an injury are examples. These modifications are contrasted with inherited attributes passed down genetically from parents to offspring.
The concept holds historical significance in evolutionary biology, particularly with the now-discredited theory of Lamarckism, which posited that such modifications could be transmitted to subsequent generations. Understanding the distinction between inherited and environmentally induced characteristics is crucial for comprehending the mechanisms of heredity and natural selection. This differentiation prevents confusion regarding the source of biological diversity and adaptation.