I submit that your use of species as the dividing line to determine who has a right to life is arbitrary.
Then what makes us different from bacon or lettuce?
A species does not have "the capacity to act as independent economic agents, that is pull their own weight in the economy and respect the rights of others," individuals within the species have that capacity.
Show me a plant or animal that deserves rights, and I will recognize those rights and help defend them!
Yes, some animals can be conditioned by humans to behave politely, do something that other human beings are willing to pay for, accept tokens for their tricks and exchange them for bananas, etc. But it takes a lot of time to train an animal like this, and its life probably isn't in danger because of its value to its owners. If a tribe of monkeys can sustain this culture, then you might have an argument, but countless experiments show that no non-human animal can.
A two year old-- or, for that matter, a senile 90 year old-- no more has that capacity than a chimp does.
A two-year-old and a senile person probably should not have full rights to liberty and property (a jury should decide that on case-by-case basis), but, unlike chimps, they should have the right to life for all the reasons I've already mentioned, which have nothing to do with intelligence.
A society which allows infanticide fails to draw a rational line for where the right to life begins: the question of whether parents have the right to kill a 6-year-old or a 12-year-old would perpetually come up. It would decrease the population growth, and allow parents to get away with unlimited child abuse, whereas having the right to life from birth would allow the minor to sue for emancipation, or have someone sue on its behalf, and/or to expose the parents' misdeeds afterwords, which would be an effective deterrent.
One could say that "it will appease a system of demagogue politicians appealing to pity rather than logic, waste money on enforcement of those victimless crimes, encourage a black market, lose its productive members to prison, etc, etc, etc." about anything that they do not believe should be against the law.
The only things that should be against the law (in a criminal sense) are violations of the Non-Aggression Principle, which I believe has a rational basis. I can prove that punishing killers of man is good and not punishing them is bad by pointing out numerous anthropological examples. Recognition of rights in human beings is essential to a civilized society. Recognition of rights in chimps only brings about the harms I've mentioned.
Besides, do you believe in the rights of the individual, or the rights of a society?
There is no such thing as a "society" as one entity, just interaction between the individual entities within it. All my comments about the way groups of people ought to function come from my own self-interest, and call upon independent action of individual human beings for the same purpose.
I recognize that the thief who robbed my neighbor's house might harm my property next, and it is in my best interest to chip in to catch him, and hopefully my neighbor would do the same if my house was robbed. If someone buys a chimp on a free market, takes it home, and kills it, how does that harm me? In fact, it is in my best interest to defend this person if some PETA nuts go after him, because maybe they'll go after my right to eat meat or wear fur next! And we all benefit from treating animals as property: the human civilization wouldn't have come very far without it.
I don't believe that scientists actually use chimpanzees for medical experimentation-- at least the kind that seriously harms or kills them. It's enormously expensive, for one thing, and unnecessary if you can use a rat instead and get just as good a result, which usually seems to be the case. If something more complex is required, they generally go for a rhesus monkey.
The reason why it's so expensive is because of all the red tape involved, which is in place because of the "animal rights" nuts. In a free society, breeding chimps wouldn't be much more expensive than breeding pigs. And using lab animals that are most similar to humans does have advantages. If a radical experimental head transplant
procedure that was never tried on humans before is your only hope of survival, would you rather it be tested on rats or chimps before you? Even if it offers a 0.01% improvement in my survival rate, I'd go with the chimp!
But I wouldn't be opposed to their gratuitous murder being against the law. If I caught someone trying to kill a chimp to have it as a "delicacy" for dinner, I would most likely do everything in my power to stop them.
Then you are a very immoral person, and I hope your initiation of aggression against your fellow man is reciprocated successfully.
If you want to protect chimps, buy them, or contribute to a charity that does. Persuade other to help you, but without using force. No one has the right to hurt a chimp that is on someone else's property!