759-13436 - Horseshoe Crab in Mangroves, Limulus polyphemus, Cancun, Yucatan, Mexico

759-13435 - Underside of Horseshoe Crab, Limulus polyphemus, Cancun, Yucatan, Mexico

759-13434 - Horseshoe Crab in Mangroves, Limulus polyphemus, Cancun, Yucatan, Mexico

759-13433 - Horseshoe Crab in Mangroves, Limulus polyphemus, Cancun, Yucatan, Mexico

832-108014 - Aerial view, Gersteinwerk power plant, Hamm, Ruhr area, North Rhine-Westphalia, Germany, Europe

1113-62804 - Shield shrimp, oldest living thing, desert region, Australia

83-12317 - Thrombolites, a variey of microbialite or living rock that produce oxygen and deposit calcium carbonate, similar to some of the earliest fossil forms of life found on Earth, Lake Clifton, Yalgorup National Park, Mandurah, Western Australia, Australia, Pacific

83-12320 - Thrombolites, a variey of microbialite or living rock that produce oxygen and deposit calcium carbonate, similar to some of the earliest fossil forms of life found on Earth, Lake Clifton, Yalgorup National Park, Mandurah, Western Australia, Australia, Pacific

83-12318 - Thrombolites, a variey of microbialite or living rock that produce oxygen and deposit calcium carbonate, similar to some of the earliest fossil forms of life found on Earth, Lake Clifton, Yalgorup National Park, Mandurah, Western Australia, Australia, Pacific

759-1644 - Spotted gar, fish scales, Lepisosteus oculatus, North america, america, USA, Florida

759-1641 - Spotted gar, Lepisosteus oculatus, North america, america, USA, Florida

759-1642 - Spotted gar, Lepisosteus oculatus, North america, america, USA, Florida

759-1643 - Spotted gar, Lepisosteus oculatus, North america, america, USA, Florida