Many fish, amphibians, reptiles, crocodilians, and mammals will go back to where they were born when they are ready to breed. Some frogs can tell the difference between different genetic matches and their own kin by slight variations in the mating call, which allows them to avoid inbreeding, whereas in other animals inbreeding may improve genetics by selecting dominant, strong genes to pass on, despite being directly or indirectly related on a genetic level. Of course, amphibians would be more susceptible to inbreeding because of their aquatic/moist environments, where parasites would have an easier time wiping out a population if they were all genetically identical. This may be why you see such amazing properties in the chemical structure of frog's skins and why frogs are so valuable to pharmaceutical and disease prevention research.
But for most animals, after a year or more, the weak ones with bad genes usually die off, so the ones that return come to pass on their genes that have allowed them to survive until breeding season.
Inbreeding from the same clutch might have negative effects over time, but I think mixing up a few males and females should have very little effect.
Recessive, negative genes usually end up in the death of the animal at a younger age, before breeding would take place. So if the breeder's animals are healthy, then I see no downside.
It's good to buy babies from older pairs, because older chameleons that are still healthy enough to breed would have better genes.
I think most animals on Madagascar are able to cope with inbreeding to a higher degree because they are from an island. Islands are nature's laboratory and small populations would always be inbreeding throughout history. This is why you probably see no large mammals, because inbreeding in mammals has more negative effects, but in reptiles it is very common.
Similar with most of the islands in the world, there are rarely large mammalian predators, and always lots of reptiles and amphibians. And usually a really really really diverse group of reptiles and amphibians at that, where many of one species would have eventually become new species through mutations from inbreeding.
In fact, I'd go so far to say that every color morph of panther chameleons is a DIRECT result of inbreeding throughout Madagascar's history. If you think about it, they are from certain locales, where only so many clutches of eggs, with only so many that survive, would have to have inbred hundreds if not thousands of times throughout history with directly or indirectly related genetic matches.
Especially SMALLER islands like Nosy Be, Nosy Mitsio, etc, they would all be very inbred, which is probably why those locales only have one or two solid colors; blue and green respectively. I don't know how big the range of Ankaramy is, but I would suspect that it is a smaller range also.
