Lois, what you describe as the "original wolf," in other words, the ancestor to modern dogs, began as neither pet nor captive. They co-existed with man at a time when our two species were on equal footing. They roamed WITH us. Wolves that were more docile/submissive or tame had a survival advantage in capitalizing on that relationship. Today's dogs are neotenized wolves. Although domesticated, which means altered genetically to accommodate our needs, in this modern world they still suffer form being leashed, fenced, and cooped up in the home all day. More captive than companion. Our lifestyles are evolving too and where at one point it was predominantly rural today its far more urban and compartmentalized. This creates difficulties for dogs that live with us because they are still roaming animals who need to socialize with other dogs in the neighborhood. As they once did in our suburbs. Domestication doesn't make a difference in those cases (see it's definition above) nor is it a blanket term as it has different meaning depending on species. There are plenty of domesticted animals that we know need more than a life in our living rooms can give them.
(on dogs) "Basically, two different species with complementary skills teamed up together, something that had never happened before and has really never happened since. " - Temple Grandin
And let's not forget the health/behavioral issues we've created in them (and virtually every animal we've domesticated) as a result of the process of single-trait selective breeding. Things were now trying to correct. There are dogs who do not possess the skills to interact with other dogs because we've inadvertently bred certain social-signal behaviors out of them. For example, a dog that does not know how to submit to an aggressor will get injured badly. Conversely a dog that does not recognize signals.
Parrots didn't team up with humans or come to be with us in the same way. In fact, we all know the means by which
parrots came to be with us...it goes without saying that they were captured. And we know it was (and continues to be) brutal and stressful with high mortality rates. Also, its a misconception that parrots live with the constant fear of becoming prey (commonly cited as a benefit of captivity). For one, Dr. Brightsmith who is head of research at Tambopata, Peru affirms that their lifestyle affords them safety from predators
Magazine Articles - Magazine Articles - What Eats Parrots? What are the major predators on parrots in the wild? . When you think about it even a bald eagle can become prey to a bobcat if it hangs around on the ground long enough over a kill. As can a vulture to a lion. Birds we don't normally associate as prey.
I can’t help but feel that Alex was stressed by the constant repetition required of scientific research... "wanna go back." And, wonder whether that stress contributed to his plucking as well as asper (which I believe he had at one point) as stress weakens the immune system through the release of the immunosuppressant cortisol. Dr. Pepperberg uncovered the intelligence that was already present in AG's and that had evolved absent of humans, as did that of whales and dolphins, or non-human primates. Because of this I find their intelligence all the more fascinating. If we knew more about their natural lives, as I wish we did, maybe we'd know what selective pressures led to such an adaptation. Pursuing this line of reasoning I could pose the question, "what's the pressure to become smart if you are provided with everything you need in life?" No challenges in life also means no need to do smart things to survive. Certainly in our human world leisure or free-time may lead an intelligent individual to invent, ponder philosophy, write poetry, etc. But we got to that point in the
first place, in part, because of our physiology (our hands could create what we envisioned), language, and what we had to do to survive as a species. Consider crows, chimpanzees, and humans all invented tools. I think crows are a great example of a sentient, cognitive, and emotional bird species co-existing with us, adjusting their behavior (and learning) to survive in our modern world, all without being captive. One can Amazon search "Gifts of the Crow" for a fascinating, scientific exploration of their talents.
I think Temple Grandin PhD's books are a must read. They cover this subject extensively, particularly "Animals in Translation." Relying heavily on scientific research and study in it's exploration. As well as the implications of such knowledge on animal welfare. As, for example, knowing that any animal is intelligent should make us think twice about keeping it in a cage. In other words, if anything, all of this tells me that pets should be simpler animals with simple needs easily met. And that this would go a long way to reducing the stress that a complex animal feels being treated as merchandise.