[Stultis]

Yeah, but in fairness that's usually by means of polyploidy (multiplicative increases in chromosome number). kstone's objections obviously don't (automatically) apply in these cases since you still have the same chromosomes that assort and pair in the same manner, you've just doubled (or tripled, quadrupled, etc) their number.

kstone seems to be asserting that if existing chromosomes mutate by fusing, breaking apart, and by other such means changing their number, then they CAN'T possibly assort and pair. This is false (as a universal assertion) but a different issue from polyploidy.

[furball4paws]

No, it's a method through hybridization, which is not polyploidy. It leads to gametes that are roughly half of each parent and new species since thay cannot cross with either parent, not having a full complement of genes from either parent. It is quite common.

[kstone]

"kstone seems to be asserting that if existing chromosomes mutate by fusing, breaking apart, and by other such means changing their number, then they CAN'T possibly assort and pair. This is false (as a universal assertion) but a different issue from polyploidy.

False. What I am asserting is that you have to have identical (or at least near-enough) fusion in both a male and female of the original species and that they have to form a mating pair in order for the novelty to be propagated and create a new species. You don't seem to be thinking this through. There are all sorts of ways to get a genetic variant. It is the small matter of PROPAGATING that novelty that is problematic.