Of or from one's ancestors
Possessed at birth
We have seen the end of hereditary monarchy.
There were no hereditary or formally elected chiefs, nor was there any vestige of monarchy.
By the time of the jurists it had become hereditary and compulsory.
If it's hereditary, then the mutation has been hidden from us for, like, maybe even hundreds of thousands of years.
With the crystallization of the feudal system in the 12th century the office of vidame, like that of avoue, had become an hereditary fief.