Practice question

Ecads are environmentally induced forms within a species, not genetically fixed races. Different conditions can produce contrasting body size, pigmentation, leaf form, or physiology through phenotypic plasticity. When those individuals are transferred to a common environment, the environmental cues become similar and their phenotypes tend to converge, making them morphologically similar. This common-garden logic distinguishes plastic responses from inherited differentiation: persistent differences would suggest genetic divergence, whereas disappearing differences indicate environmental control. Ecads therefore need not become sterile or genetically diverse when conditions are standardized. At population level, this mechanism can influence abundance, coexistence, and evolutionary selection. Separating immediate individual effects from longer-term community outcomes gives the selected concept a clearer ecological meaning and avoids relying only on memorized terminology. The relevant evidence concerns process rather than wording alone. Linking the described pattern to energetic returns, fitness consequences, or receiver responses makes the inference biologically coherent and distinguishes it from the competing alternatives.