Watch | Endangered Olive Ridley marine turtles lay eggs on Mexican beach

Thousands of nesting female Olive Ridley marine turtles arrive at La Escobilla beach, a protected beach, in Mexico to lay their eggs in the sand. It's their annual migration, a sign that life is about to burst forth from scorched grains of sand. Every year from the start of August to the end of September, these tiny black baby reptiles haul themselves to the sand's surface and painstakingly crawl to the sea. Small enough at birth to fit into a child's palm, females will hit land again as adults in 25 to 30 years time, thanks to a genetic homing device that makes them return to the beach where they hatched so as to carry on the reproductive process. Males will never return.