The exact form of the error will depend on the concept of species that the critic holds. According to the morphological species concept, species are defined by the similarity of appearance of their members. The varieties of dogs would serve as an example of artificially created new species in the morphological sense. An African hunting dog and a wolf, for instance, are classified as separate subfamilies, but they look more alike than a Pekinese and a Great Dane. New species have been created in the reproductive sense, too.
Most examples come from agriculture and horticulture.
They can interbreed with other members of their own species, but not with members of any other species. Then evolution is certainly not any sort of a fact, since there is NO evidence that supports it. Our primary evidence for evolution would necessarily be found in the fossil record. Others point out that fossils record offers no firm evidence for such gradual change. It is evolutionists who have denied the reality of the fossil record.