See snakelike necks, alligatorish backs, and a turtle with two heads. (Full story: http://on.natgeo.com/1sUf8C0)
  1. Reach Out, I’ll Be There
    Fullsizerender
    The Reimann’s snake-necked turtle ("Chelodina reimanni") is so named because of its long neck. (Photo by Joel Sartore, National Geographic Photo Ark, Zoo Atlanta)
  2. Two Heads Are Better Than …
    Static
    Two-headed yellow-bellied sliders ("Trachemys scripta scripta") can be found in Atlantic drainages along the southeastern border of the United States. (Photo by Joel Sartore, National Geographic Photo Ark)
  3. Open Wide
    Static
    Female alligator snapping turtles ("Macroclemys temminckii") usually don’t weigh more than 50 pounds (23 kilograms), but male ones are huge: They average 175 pounds (80 kilograms). Some even surpass 220 pounds (100 kilograms). (Photo by Joel Sartore, National Geographic Photo Ark)
  4. Peekaboo
    Fullsizerender 3
    This Mississippi diamondback terrapin ("Malaclemys terrapin") is just trying to see what’s up. (Photo by Joel Sartore, National Geographic Photo Ark)
  5. The Nose Knows
    Fullsizerender 4
    This particular mata mata turtle ("Chelus fimbriatus") comes from Madagascar. (Photo by Joel Sartore, National Geographic Photo Ark)
  6. Jabba the Turtle?
    Static
    Smooth softshell turtles ("Apalone mutica") reportedly have “high reproductive potential by turtle standards”—despite the fact that this one resembles poop. (Photo by Joel Sartore, National Geographic Photo Ark)
  7. What Are You Looking At?
    Fullsizerender 1
    This diamondback terrapin ("Malaclemys terrapin") comes from Bermuda. (Photo by Joel Sartore, National Geographic Photo Ark)
  8. Whee!
    Static
    When these baby ornate box turtles ("Terrapene ornata") were first born, they were only about three centimeters long. (Photo by Joel Sartore, National Geographic Photo Ark)
  9. Indecent Exposure
    Static
    A red-bellied short-necked turtle ("Emydura subglobosa") shows off its colorful side. (Photo by Joel Sartore, National Geographic Photo Ark, Fort Worth Zoo)
  10. A Well-Designed Shell
    Fullsizerender 4
    The ornate-looking Indochinese box turtle ("Cuora galbinifrons") is a critically endangered species found in China, Laos, and Vietnam. (Photo by Joel Sartore, National Geographic Photo Ark)
  11. Shells—A Versatile Accessory
    Fullsizerender
    These Pearl River map turtles ("Graptemys gibbonsi") are an endangered species. Since 1950, their population has declined by 80 to 90 percent. (Photo by Joel Sartore, National Geographic Photo Ark)
  12. Pre-Growth Spurt
    Static
    Green sea turtles ("Chelonia mydas"), an endangered species, are among the largest sea turtles in the world. When this baby grows up, it could weigh up to 700 pounds (317.5 kilograms). (Photo by Joel Sartore, National Geographic Photo Ark)
  13. Won’t Get Fooled Again
    Fullsizerender 2
    A false map turtle ("Graptemys pseudogeographica") has lines across its shell, but they won’t lead you anywhere. (Photo by Joel Sartore, National Geographic Photo Ark)
  14. Starry Night
    Fullsizerender 3
    This Burmese starred tortoise ("Geochelone platynota"), native to Myanmar, is an endangered species. (Photo by Joel Sartore, National Geographic Photo Ark)
  15. Reach for the Sky
    Fullsizerender 4
    This flexible bog turtle ("Glyptemys muhlenbergii") is a critically endangered species. It lives in the eastern United States. (Photo by Joel Sartore, National Geographic Photo Ark)
  16. Protect Ya Neck
    Fullsizerender
    Broad-shelled long-necked turtles ("Chelodina expansa") were named for obvious reasons. (Photo by Joel Sartore, National Geographic Photo Ark)
  17. Another Softie
    Fullsizerender 1
    Gulf Coast smooth softshell turtles ("Apalone mutica calvata") are a subspecies of smooth softshell turtles. (Photo by Joel Sartore, National Geographic Photo Ark)