Some animal rights activists are getting hot and bothered because some people sell coats made partly of dog fur – which is illegal in the United States.
Now, measures to prevent fraud (like selling fake fake fur under the guise of real fake fur) are one thing. But we think that people should be allowed to sell real dog and cat fur if they want to. Dogs were created by nature and human civilisation through natural and artificial selection. Dogs themselves can't generate new ideas, although people can train them to do stereotypical things like fetching sticks. So everything that might make a dog unique can be easily recreated by getting another dog of the same breed and treating it in a similar way.
If someone acquires a psychological attachment to a dog that they own – or for that matter to a picture that they own of a dog that never existed – then of course it should be a crime for someone else to destroy the dog or the picture. But for the same reason, if somebody chooses to kill their dog, that is an innocuous act. They can, for example, easily replace the dog with another that is just like it. If they also sell the dog's fur, everyone concerned is better off.
By contrast, human beings are capable of generating new ideas. So if somebody kills a human being they may have destroyed unique ideas that could make the world better. They cannot be replaced by simply treating another human in a similar way – even if that were a moral thing to do. Even if a person appears to have no good ideas, we may simply misunderstand the merits of his ideas. That is why we set up institutions, such as law and moral traditions, to ensure that choices between rival ideas can be made on the basis of reason, not violence. That is why killing a human being is wrong, except as a necessary consequence of defending another human being.
And that is why human beings have rights, while dogs and other animals do not.