If a Species changes into a New Species, is that classed as Evolution? -How can this happen?

-Yes it is, as it still links with the Phenotype changes, which is all due to the Genotype changing from the Inherited Characteristics -This can happen due to a Physical Barrier separating 2 Populations of a Species. -The Conditions on either side will most likely be Different, so that means the Phenotypes will change accordingly to survive the Longest, therefore changing the Populations, until they can not Breed