In the deep, the faintest glow of bioluminescence can give a hunter away. Researchers have identified at least 16 fish species whose skin reflects less than 0.5% of light, a black that rivals the best human-made materials. The trick is a dense layer of melanin granules whose size and shape are perfectly tuned to trap photons.
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.