The age of Hermann's tortoises (Testudo hermanni hermanni) can be assessed by the skeletal growth marks of their bones and those of the horny scales of the shell. The growth rings of the scales constitute annual marks making it possible to assess the age of an individual until its sexual maturity (around 12-13 years), unlike the bony marks that extend until the 20th year. The average longevity of about sixty years of Hermann's tortoise is explained by the adaptability of its metabolism and the protection offered by its shell beyond the first six or seven years.