Can animals make conscious choices? With the exception of some higher primates, no.
As far as I can tell, there is no conclusive evidence that higher primates are smarter than dolphins, elephants or crows. There may be more data about higher primates, but that stems from greater interest for species that are closer to us. Certainly, all of these species are capable of conscious choices. In fact, I will go much further, for I believe that every single animal species is capable of conscious choice.
We have been so consistently wrong in estimating animal capability that it wouldn't hurt to give them the benefit of doubt. Animals systemically outperform our expectations, as we get better at testing them. Besides, seriously, what the fuck is it about "conscious choice" that is so extraordinary that only humans can do it? Conscious choice is mundane. It's simple. It's boring. There is nothing remotely extraordinary about conscious choice. Why should it be human specific, except to satisfy humanity's delusion of grandeur? Get over yourself.
Can animals communicate with other animals and specialize tasks (and when I say specialize, I mean consciously specialize, not be born specialists like ants)? No.
Oh. Sure, if you say so. But I still have to ask. First, I have to ask if you actually made an effort to research the topic. Second, I have to ask if you realize that "specialization" is not necessarily something that has been extensively tested, and that many behaviors that natural specimens do not exhibit will occur in the proper situation. I mean, humans right now communicate and specialize way more than they ever did in the past.
Are animals rational? No.
Neither are humans, for the most part. I mean, frankly, if you think humans are rational animals, your standards of rationality must be pretty dreadful. Or perhaps mine are too high.
But nonetheless, you're pulling these assertions straight out of your ass. How do you test rationality? Do you seriously think that you can make a rationality test that is so easy that 99.9% of humans would pass it, and yet 99.9% of animals would fail it? Keep in mind that tests designed by humans will necessarily be slanted in our favor. It's not because animals can't understand our language that they're complete retards - it's not like we are much better at understand theirs.
(and before you say "babies/children", babies and children are members of the species homo sapiens, which do meet the above criteria. Rights are absolute within a given species.)
Oh, really? Why? Slavery is a pervasive tendency of human society. Their proponents certainly didn't think rights were absolute within a given species. If they saw our society, they might think it is preposterous for all these races to be treated as equals. And honestly, what rational arguments can you give against gradating rights within a species? The answer would be: none. Because there is no rational argument against it. In fact, one could easily argue that it would be rational for rights to be proportional to some measure of intelligence, because the smarter one is, the better use he or she can make of their rights. Thus the smart would enslave the dumb. I am of course not saying I want to live in such a society, because I have the same cultural bias that you have. But you have to realize that the argument to give uniform rights to all humans is not rational. It is empathic.
And the reason why humans have more rights than animals is extremely simple: we have more rights because we are stronger and we can enforce them. There is no other justification whatsoever. If we want to give animals rights, it is our prerogative.
While there are some exceptions to the above criteria (and provisions could be made for them, though it's not like every dolphin or whale in the ocean is even close to sentinent), for the most part, animals are not sentinent, therefore they are not entitled to the same rights as humans.
There is nothing about humans that isn't found elsewhere in the animal kingdom. You really need to step out of that anthropocentrism. Humanity is not about having certain exclusive traits, it's about the degree and extent to which we express certain traits. Do you think that sentience or intelligence just automagically appeared in humans without any precursor whatsoever? That's not how evolution works, and you're fooling yourself if you think other species aren't close, in evolutionary terms (that means millions of years), from being our equals.
Heck, human-like intelligence might have evolved before, but died out without leaving a trace. Right now, there might be a bunch of mutant parrots in New Zealand that are significantly more capable than any of their cousins, and could learn language as easily as we do. How do you know?
Why feel the need to glorify the human race and seek excuses to give ourselves more rights? We don't need a goddamn excuse. We're the strongest. Your arguments are literally a copy paste of the arguments proponents of slavery would use, and they stink just as much. It's a shame you can't see it, because
they couldn't see it either.
So we shouldn't reference the thoughts of a person who specializes in natural rights when discussing whether to extend those rights past their traditional boundary of humans to non-humans?
Not when they don't get their facts straight.
Of course, all these examples are quite interesting, but is this enough to say that even highly intelligent animals "think" in a human sense? I would argue that higher primates "think" in a very close to human sense, that dolphins think in a similar sense, but other animals? Not enough.
Oh, so they have to think "in a human sense" now? How convenient.
Also, it is not so much the ability to think on a human level that should get animals a certain degree of rights, but rather the ability to suffer. If something can suffer, you shouldn’t do anything to make it suffer more than it has to anyway unless you have a sufficiently good reason.
"Suffering" might be difficult to measure, though. You may be able to figure out that something suffers because they are undergoing identical processes to those that happen in us when we suffer, but if these processes don't happen or are inapplicable (as might be the case for a machine), you can't conclude that they don't suffer. I don't see any reason why a machine could not suffer in a meaningful sense, but I don't see how we could actually determine whether they do or not, if they can't communicate it. But it's not just machines. For instance, you could have some biological organism without a nervous system, but which can acquire the information it needs from other senses, and suffers all the same.
And then there's the problem of what you would do with humans that can't suffer. I mean, certainly, some cannot suffer physically, and it's not a big stretch to say that some are so numb emotionally that they effectively don't suffer. Do they still have rights?
In the end, there is no "rational" way to assign rights, or at least, there is no systematic way to do it. The way you present is a purely empathic argument (which I support, because it appeals to my empathy as well), but it has limits.