Hey everyone, I have 8 desert tortoises that are 18 months old and are all 6 to 7-1/2". I know they are deserts because I have had the parents for over 30 yrs. I also have 3 hatchlings that are 6 months old and are 3". The adult male is About 14" and the female is 12". In captivity they grow much faster than in the wild. They have never hibernated, just keep growing. The adults do hibernate outdoors and are just coming out occasionally now.