This mammal nurses its young, yet it lays eggs, and it has no nipples: milk seeps out through its skin. Underwater, it shuts its eyes, ears and nostrils and hunts using tens of thousands of electroreceptors in its bill. Males also carry a venomous spur on their hind legs. The first European naturalists to examine one suspected a hoax.
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.