A study of the tortoises at Santa Rosa’s Safari West Park is providing some new insight about the aging process. The study, published in the journal Science, suggests tortoises can keep growing much longer than humans, other mammals, and birds can. It shows certain species of turtles and tortoises can grow and live for decades, in the right environment. Data for the study was recorded at Safari West Park, along with other zoos and aquariums. Three-quarters of the 52 turtle and tortoise species studied showed an extremely slow aging process. And, 80-percent of the animals aged slower than modern humans do.