A smooth stick insect (Clitarchus hookeri) photographed at Auckland Zoo in New Zealand
Photograph by Joël Sartore, National Geographic Photo ArkGray's Malayan stick insects (Lonchodes brevipes) photographed at Houston Zoo in Texas
Photograph by Joël Sartore, National Geographic Photo ArkA giant prickly stick insect (Extatosoma tiaratum) photographed at Omaha's Henry Doorly Zoo and Aquarium in Nebraska
Photograph by Joël Sartore, National Geographic Photo ArkPeruvian firesticks (Oreophoetes peruana) photographed at Fort Worth Zoo in Texas
Photograph by Joël Sartore, National Geographic Photo ArkA Lord Howe Island stick insect (Dryococelus australis) photographed at Melbourne Zoo in Australia
Photograph by Joël Sartore, National Geographic Photo ArkTwo mating thorny stick insects (Aretaon asperrimus) photographed at Rolling Hills Wildlife Adventure in Salina, Kansas
Photograph by Joël Sartore, National Geographic Photo ArkCelebes leaf insects (Phyllium celebicum) photographed at Omaha's Henry Doorly Zoo and Aquarium in Nebraska
Photograph by Joël Sartore, National Geographic Photo ArkTwo mating giant walking sticks (Megaphasma dentricus) photographed at Dallas Zoo in Texas
Photograph by Joël Sartore, National Geographic Photo Ark