The process of gradual evolutionary change over time.

Both micro- and macroevolutionary change is gradual; see also Punctuated Equilibrium

Phyletic gradualism is a theory that addresses the rate of evolutionary changes over time. In this theory, evolutionary changes occur gradually over time, at a relatively slow, even rate. Phyletic gradualism was defined by Eldredge and Gould to contrast with their theory of phyletic equilibria.

see Gradualism.

The classic palaeontological view that species evolve by gradual lineage evolution (anagenesis) and splitting (speciation) as a subsidiary process.

Phyletic gradualism is a macroevolutionary hypothesis rooted in uniformitarianism. The hypothesis states that species continue to adapt to new challenges over the course of their history, gradually becoming new species. Gradualism holds that every individual is the same species as its parents, and that there is no clear line of demarcation between the old species and the new species.