Wallace effect

The Wallace effect refers to a phenomenon in evolutionary biology where speciation, or the formation of new species, is driven by a reproductive barrier. This occurs when populations become separated and develop distinct traits or behaviors that lead to decreased interbreeding. Over time, these differences can become significant enough that even if the populations reunite, they no longer mate successfully. Essentially, the Wallace effect highlights how separation and adaptation can lead to the emergence of distinct species, contributing to biodiversity. It underscores the importance of reproductive isolation in the process of evolution.