I don't think it's very meaningful to talk about rights out of the context of people's government, so how that idea would apply to animals I don't see.
Rights can exist according to people's moral view. That is, there may be a perception that certain rights
are "just". In dictatorships, the common people often feel a ruler is harsh and unjust, that people have a right to be treated better. During the Nazi reign, the laws were seen as being unjust by those within and without the regime that resisted. Some people may have been deceived as to what was happening. Obviously, some people agreed with the regime.
In the case of the animals jetson mentioned, are you asking human perception of the animal rights or the perception of the giraffes themselves. Which giraffes? From the same herd or from another one. What sort of behavior occurs within the herd, what rules are enforced. How does one giraffe act when another is being treated harshly?
There's definitely no guarantee for someone's rights, but I believe a person has a better chance in a society in having rights when the society is based on recognizing some natural-rights, and not just man made rights.....
If you read the bible, all of the societies described were dictatorships and theocracies. The rights as we see them in western democracy don't exist and nobody expects them to.
One can go further to say, that slaves are instructed to
respect their masters.
Thus, all our democratic rights are in fact
man-made:
- the right to free speech
- the right to pursuit of happiness
- etc
And yes, technically one could say they are 'man made' in the context of the fact that people have to define them, but they are not defined as being given to people by other people, which is the important point.
If they were not "defined" by people in the sense
language or culture is defined, where do they come from?
At least in the case of giraffes, this claim of yours makes sense. Whatever the order is in a giraffe herd, there is no evidence that it is learned. Its probably instinctive.