[Jack Black]

What about the camel, elephant, water buffalo, yak, llama, and alpaca?

[Old Professer]

Only the elephant can dance, and it poorly.

[Arthalion]

What about the camel, elephant, water buffalo, yak, llama, and alpaca?

There's a difference between domestication and taming. The use of the animals you mention are all still heavily dependent on wild stock to supplement domestic breeding. With domesticated animals, you have a closed system leading to adaptations specifically for human use. With tamed animals, you still have an animal identical to its wild counterpart, but which is simply living under the control of man.

Pigs, sheep, and dogs are domesticated. Elephant and yak are tamed.