At dusk, billions of small animals, from crustaceans to lanternfish and squid, rise hundreds of meters from the depths to feed near the surface, then sink back down at dawn to escape predators that hunt by sight. During World War II, sonar operators even mistook this living layer for a false seafloor.
In 2022, a young tagged bar-tailed godwit flew from Alaska to Tasmania in about 11 days of nonstop flight, covering 13,560 km without eating, drinking or landing. Before departure, these birds pile on huge fat reserves and shrink their digestive organs, which are useless during the journey.
To escape rivals, a dung beetle rolls its ball of dung in a straight line. At night, it holds its course using the glowing band of the Milky Way. In a planetarium, researchers showed that beetles rolled straight under a starry sky but wandered aimlessly when the galaxy was switched off. It was the first animal known to navigate this way.