The term "macroevolution" frequently arises within the context of the evolution/creation debate, usually used by creationists alleging a significant difference between the evolutionary changes observed in field and laboratory studies and the larger scale macroevolutionary changes that scientists believe to have taken thousands or millions of years to occur. They accept that evolutionary change is possible within what they call "kinds" ("microevolution"), but deny that one "kind" can evolve into another ("macroevolution"). Contrary to this belief among the anti-evolution movement proponents, evolution of life forms beyond the species level ("macroevolution", i.e. speciation in a specific case) has indeed been observed multiple times under both controlled laboratory conditions and in nature. In creation science, creationists accepted speciation as occurring within a "created kind" or "baramin", but objected to what they called "third level-macroevolution" of a new genus or higher rank in taxonomy. Generally, there is ambiguity as to where they draw a line on "species", "created kinds", etc. and what events and lineages fall within the rubric of microevolution or macroevolution. The claim that macroevolution does not occur, or is impossible, is not supported by the scientific community.
Such claims are rejected by the scientific community on the basis of ample evidence that macroevolution is an active process both presently and in the past. The terms macroevolution and microevolution relate to the same processes operating at different scales, but creationist claims misuse the terms in a vaguely defined way which does not accurately reflect scientific usage, acknowledging well observed evolution as "microevolution" and denying that "macroevolution" takes place. Evolutionary theory (including macroevolutionary change) remains the dominant scientific paradigm for explaining the origins of Earth's biodiversity. Its occurrence is not disputed within the scientific community. While details of macroevolution are continuously studied by the scientific community, the overall theory behind macroevolution (i.e. common descent) has been overwhelmingly consistent with empirical data. Predictions of empirical data from the theory of common descent have been so consistent that biologists often refer to it as the "fact of evolution".
http://en.wikipedia.org/wiki/Macroevolution
