system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: When can a species be mutated much enough to be considered an entirely new species?

Since evolution happens through mutation after every generation, when can a species mutates so much that it is considered an entirely new species? Would there be a point when the parents considered one species while their children are considered an entirely new species?
gpt
Species are considered different if they can't produce fertile offspring. It doesn't change in one generation. Different species are very vague expression though because there are many animals that are concerned as different species even they can produce fertile offspring just because they live separately and don't breed in nature.