First things first: what is domestication? Domestication is the creation of a population of living things, distinct in some way from their wild ancestors, that are selectively bred by humans. The main function of domestication involves use of those living things for food, labour, companionship or ornamentation. As evidenced by the extraordinary number and variety of domestic plants and animals, it’s either that we’re really good at it or that it’s really easy once you’re smart enough to wilfully shape the evolution of other living things. Or both. Note that domestication is not simply the grabbing and taming of animals from the wild.

While – when thinking of animals – we typically associate domestication with mammals and birds, don’t forget that animals of virtually all major groups can be domesticated, in theory. Witness domestic insects (Chinese silk moth Bombyx mori and Honeybee Apis mellifera) and fish (Goldfish Carassius auratus, among others) (Zeuner 1964). An argument has been made that there aren’t, technically speaking, any domesticated squamates, turtles or amphibians, but a counter-argument is that we’re actually pretty close to such animals being in existence (look at – for example – the many captive morphs of bearded dragon, some of which lack scales and could not exist outside of human care) and there’s no reason why they couldn’t exist given sufficient selective breeding. Time is one of the key factors here. We could – potentially, perhaps – have giant stripy domestic Komodo dragons by now if only we’d started a selective breeding project a few centuries ago [UPDATE: as discussed in the comments, an argument can be made that the ancient Egyptians domesticated crocodylians].