While conceding that selection may modify a given species and lead to closely related species, anti-evolutionists point out that a dog remains dog-like and a cat remains cat-like. Selection has not turned a dog into a cat or any other sort of animal. This objection involves a misunderstanding; there is no claim in evolution that dogs evolved into cats, or vise versa; much less that monkeys (chimpanzees) evolved into humans. The evolutionary claim is that two related animals are derived form a single ancestral population via speciation. Furthermore, as verified by modern dating methods, tens, indeed hundreds of millions of years are involved in the natural’s speciation process. This means millions of generations with selection each generation. (Have students reflect on the dimension of a million. One thousand years is difficult to contemplate; one million is one thousand thousands.
If you are interested, additional arguments against evolution and scientific rebuttals are given in the following article from “Scientific American”.
https://www.scientificamerican.com/article/15-answers-to-creationist/