sentences:  During growth, through thickening the tooth morphology changed so much that, had the association of young and adult skeletons on the Dry Island bonebed not proven they belonged to the same taxon, the teeth of juveniles would likely have been identified by statistical analysis as those of a different species.Most known "Albertosaurus" individuals were aged 14 years or more at the time of death.However, the youngest individual known is a juvenile two-year-old, and the oldest is an adult 28-year-old.