AP BIOLOGY

Detailed explanation-1: -In modern biology, gradualism, or “phyletic gradualism, ” refers primarily to a pattern of sustained, directional, and incremental evolutionary change over a long period during the history of a species.

Detailed explanation-2: -Gradualism is selection and variation that happens more gradually.

Detailed explanation-3: -Gradualism, from the Latin gradus ("step"), is a hypothesis, a theory or a tenet assuming that change comes about gradually or that variation is gradual in nature and happens over time as opposed to in large steps. Uniformitarianism, incrementalism, and reformism are similar concepts.

Detailed explanation-4: -The slow gradual change in a species over time is called: Evolution.