Large wrought stones recovered from the site of the Roman Bridge that spanned the River North Tyne dating from AD 13, Cilurnum (Chesters Roman Fort), Hadrian's Wall, UNESCO World Heritage Site, Chollerford, Northumbria National Park, England, United Kingdom, Europe

Large wrought stones recovered from the site of the Roman Bridge that spanned the River North Tyne dating from AD 138, Cilurnum (Chesters Roman Fort), Hadrian's Wall, UNESCO World Heritage Site, Chollerford, Northumbria National Park, England, United Kingdom, Europe

Sand for building recovered from the Tiracol River, Goa, India, Asia

Anchor display on the shore of Pearl Harbour, war memorial; Oahu, Hawaii, United States of America

Submerged alligator (Alligator mississippiensis) is only visible with his armored back poking above placid waters as he hunts on the muddy bottom of the Okefenokee Swamp. The reptiles skin has embedded bony plates called osteoderms or scutes. Alligator populations are considered to have recovered from overharvesting pressures through supplemental farming practices and protections placed on wild animals. However, the species is still federally listed as threatened because it looks like the American crocodile, which is endangered, Georgia, United States of America

Young alligator hatchling (Alligator mississippiensis) suns on a sunken log in the Okefenokee Swamp. Mothers aggressively guard the nests when until the juveniles begin hunting on their own. American alligators were once threatened from hunting but with protections have recovered although hatchlings are vulnerable to predators, Georgia, United States of America

Remarkable flysch formations of Deba, Basque Coast Geopark, Basque Country, Spain. Flysch formed at the end of the Mesozoic era in the Cretaceous - flyschs are formed by sediment accumulation following repeated submarine avalanches, due to earthquakes, and producing after compaction and crystallization very regular layers of sandstone and limestone here recovered by Pyrenean orogeny and released by erosion.

Remarkable flysch formations of Deba, Basque Coast Geopark, Basque Country, Spain. Flysch formed at the end of the Mesozoic era in the Cretaceous - flyschs are formed by sediment accumulation following repeated submarine avalanches, due to earthquakes, and producing after compaction and crystallization very regular layers of sandstone and limestone here recovered by Pyrenean orogeny and released by erosion.

Kelp Gull (Larus dominicanus), adult having recovered a fish, Cobquecura, VIII Region of Biobío, Chile