LIFE SCIENCE

Detailed explanation-1: -Phyletic gradualism is a model of evolution which theorizes that most speciation is slow, uniform and gradual. When evolution occurs in this mode, it is usually by the steady transformation of a whole species into a new one (through a process called anagenesis).

Detailed explanation-2: -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-3: -So, the correct answer is ‘Gradualism’.

Detailed explanation-4: -Evolution that occurs over a long period of time is called macroevolution. It might take place over millions of years. This scale of evolution occurs above the level of the species.