Well, I suppose it is if you pull a couple of quotation marks out of nowhere and simply assert that it's only a "loss of genetic information". Of course that doesn't reflect that there is merely a difference in alleles, a difference in feeding patterns, a difference in growth and seasonality, etc.
There's nothing in what 49th posted to tell you that this is due to a "loss of genetic information" in either population, let alone in both. Indeed, at least between both populations collectively, there has clearly been a gain in genetic information simply from the fact that they have different alleles (different versions of some of the same genes, which means more versions in total).
Besides, there's no rule that evolution can't occur from the loss of genetic information. It can occur that way, and/or from a gain of information, and/or from the content of genetic information merely changing. ALL of those things (if they become fixed in actual populations of living organisms) are evolution by definition and by fact.
No they aren't (or rather they are micro-evolution), but they are not real "macro-evolution" becuause they are just variation within kind:
Lets look at another example: once there were on a few type of Canine Dog,but now many would you call any of these (from the small tea-cup poodle to the Great Dane) not dogs: My prediction: NO, but that doesn't mean that it would be easy for a great dane and tea-cup poodle to mate outside the scientific lab. There has clearly been genetic loss on both frots one lost in the info to be "big" and one lost the info to be "small" as part of their genetic changes (and that is just part of the changes). the same can be said of these flys. Clearly there ancestors had both, but gentic variaton and conditions caused these to become seperated (and not contain new genetic information just because of the changes that were inherent to begin with)..They are both variation within kind, not a whole new "kind"/species.