I do agree the overseas obsession with deformation is weird, especially the tatooing and tail clipping (heart parrots make me angry) which is KNOWN to decrease the lifespan of the fish and make them more susceptible to disease. It's as bad as the maiming of dogs by ear cropping and tail chopping. It's human vanity and nothing else.
Okay, stuff like that is so extreme that it's easy for us to agree on it. We all have our limits as to what is or is not acceptable, and if one goes far enough to either extreme eventually one gets into territory that everyone agrees is bad...although
somebody is buying those things, so...?
Nothing in nature is 'pure' so no point in that tip. Humans categorize species into groups for ease of identification. Habitats change over time and hybrids occur naturally. Who's to say the species we think are 'pure' aren't the result of hybrids in the distant past? Land masses have moved and so have the oceans and waterways. Areas once under water are now land. Evolution, the real deal. Not the cute systemic stuff packaged neatly for convenience.
Here's where you have entered into the No Man's Land where opinions differ. Some are correct (like mine...) and some are not (like...okay, I won't do that
). And that's okay, as long as no harm is done and everyone is happy to do their own thing. When you get to the point...and we are definitely at that point...where a significant percentage of the fish in a LFS are mysterious unknown hybrid mutts, developed as a result of breeding "projects" that basically consist of "Gee...this might be cool...", well, it still isn't necessarily dangerous, just confusing and potentially annoying to some. Fortunately, it isn't very likely that these man-made things are going to get back into the wild gene pool and pollute it...but if it does happen, it can quite literally breed "pure" species out of existence. A species can become extinct if there are no individuals left that do not have some mixed genealogy in their make-up. I haven't followed it closely, but at one point there was concern that the American Bison was technically becoming extinct simply because there were no pure wild-strain animals left; they all had some admixture of domestic cattle in their make-up, so they weren't really bison anymore.
I chuckle when one of these gits'n'shiggles breeders earnestly proclaims "Oh, it's just an experiment; I would
never let these Piranha X Pleco hybrids out of my house!" Please! For every one of them that thinks he is being responsible by taking that stance, there are likely dozens that don't even consider it.
And please, if you are going to defend mutts, do it honestly. Certainly many natural species that are considered "pure" species are the result of hybridization in the past; if the hybrid proved to be superior in some way that allowed it to compete with, or even out-compete, its ancestors then it survived and thrived...yep, just as you say, evolution. But evolution is powered by
natural selection; the hybrid mutt only survives if it is somehow better suited to survive. Bubble-eyes and short-bodies and long-fins and other weird-ass critters like Parrots are the exact opposite of that; they are the result of
un-natural selection. People looking to make a buck select the individuals to breed who show whatever goofy trait the breeder thinks will sell, despite the fact that most of these traits would sentence the thing to a short unhappy life in a natural setting. That's not evolution; it's
devolution.
So dig it, any serious fishkeeper has a short list
Get what you want
Take care of it to the best of your ability
Enjoy, appreciate, interact