I admit, it's been a while since I've read my Smith, Locke, Jefferson, et alia, but I will try to explain what I mean. Bear in mind it's just my opinion. When I say rights are inherent, it means you are endowed with them at birth and all humans have had these rights since the dawn of man, whether or not they were recognized as such. Rights are not granted by the state. If they were granted by the state, they would be priviledges. While the state may not recognize your right to life and may take your life against your will, it would still be a case of the state taking away your right to life, regardless of the process the state used to decide that act.
So your cavemen struggling to survive expressed that inherent right to life, and to live free and pursue his own interests, even if he didn't know that that was what he was doing. The point at which the state emerges and denies man his ability to live or to be free is the point at which these inherent rights are violated. The state is a collection of people whose purpose is to regulate the peaceful, social interaction of people. Yet the concept of state has expanded it's mandate and appropriated the power to determine who should live, die, be free or in the case of Islamic governments, the power to determine all aspects of people's lives. But this is simply a case of might makes right and denies their citizens in modern times even the most basic of rights as expressed by the cavemen.
I wish I could say this all more eloquently, but I'm in a self-imposed political exile. Like the old axiom, use it or lose it, I have lost some of my ability to express things as clearly and succinctly as I once could.