Here's a breakdown:

* Microevolution refers to changes in allele frequencies within a population over time. These changes can be driven by factors like natural selection, genetic drift, gene flow, and mutations.

* Macroevolution refers to changes above the species level, encompassing processes like speciation, extinction, and long-term trends in evolution.

Think of it this way:

* Microevolution is like the slow, gradual changes in the color of a butterfly's wings over generations.

* Macroevolution is like the emergence of entirely new species, such as the evolution of dinosaurs from their reptilian ancestors.

Microevolution is the foundation of macroevolution. The gradual changes that occur at the microevolutionary level can eventually lead to the large-scale changes we see in macroevolution.