-_- but the post you were responding to wasn't about this topic. I don't interrupt conversations with material from previous ones unless said material contradicts claims currently being made. Which is not the case here.
Furthermore, I have never once stated that it is typical for a single mutation to result in a species transition. It is hypothetically possible (I can only imagine it occurring in asexual species and species with hermaphrodites). Plus, the definition of species as it applies to bacteria which uses percent genomic similarity to define species most definitely means that an organism can transition to another species via a single ADDITIONAL mutation (because populations are mutating continuously). However, it is extremely unlikely that a single mutation in a bacterium would be so large as to result in the offspring being a different species than the parent.
-_- by that logic, humans and chimpanzees are the same species. How do you not realize that the lowest taxonomy category shared by all lizards is broader than the one humans share with chimps? How can you even justify this view when the capacity to reproduce to produce fertile offspring is such a huge component in species labels in animals?
So sayeth the guy that thinks my bearded dragon is the same species as a Komodo dragon. Even the people that try to categorize animals as "kinds" generally don't try to say that "kinds" means species or assert that all lizards are the same species.
-_- to assume that bacteria would have to become "not bacteria" to demonstrate evolution is more outrageous than viewing a lineage of dogs giving rise to a 6 legged herbivore as "not evolution". That's a kingdom level classification transition, of which there have been less than 10 in the over 3.5 billion years life has existed on this planet. For that to even occur would likely demand the annihilation of all members of at least one of the already existing kingdoms just so that enough niches are opened up.
Lol, what? All I said is that the only thing mutations can't feasibly do is make reproductively incompatible species become compatible. The reason isn't because one can't determine the changes necessary to accomplish it, but rather that the mutations required for it to occur are extremely numerous, specific, and have no selective pressures for them. There are tons of mutations that can result in extra limbs, muscles, the formation of eyes, etc. But in order for two incompatible lineages to re-merge, both populations would have to experience extraordinarily similar mutations in conjunction with mutations that eliminate factors that made them incompatible to begin with, such as differences in chromosome number.
No such thing has ever been observed, so I see no issues here. Care to point the ones you see out? That is, there is no indication ever of organisms that can't reproduce with each other being able to do so later on thanks to mutation. Perhaps from hybridization with a third species that is compatible with both, but never via mutation. Evolution doesn't have to explain phenomena that have never been observed; no theory has to do that.