picture of the day: twitter.com/IrinaGreenVoic… — Irina Tikhomirova (@IrinaGreenVoice) June 21, 2012 Tortoises are a family of land-dwelling reptiles in the order Testudines . Like their marine cousins, the sea turtles , tortoises are shielded from predators by a shell. The top part of the shell is the carapace , the underside