* Variation in chromosome count (ploidy) is impossible in evolution. One member of a species with 2 sets of chromosomes cannot mate with a member with 4. Thus, for the chromosome count of a species to change (and thus account for the variety of counts in nature) a vast portion of a species would have to evolve a new chromosome set simultaneously. | * Variation in chromosome count (ploidy) is impossible in evolution. One member of a species with 2 sets of chromosomes cannot mate with a member with 4. Thus, for the chromosome count of a species to change (and thus account for the variety of counts in nature) a vast portion of a species would have to evolve a new chromosome set simultaneously. |