What an Owl Knows: The New Science of the World's Most Enigmatic Birds

related not to falcons or nightjars but to a group of day-active birds that includes toucans, trogons, hoopoes, hornbills, woodpeckers, kingfishers, and bee-eaters.

But new research shows that owls are most closely

An owl like this will eat an astounding 250 to 350 possums a year, nearly one a day.

from the diminutive Elf Owl, a little nugget of a bird, impish, troll-like, about the size of a small pine cone and the weight of eight stacked nickels, to the massive Eurasian Eagle Owl, which can take a young deer;

As with all owls, the indigestible parts—fur, bones, feathers, claws—are sequestered in the stomach and compressed into a pellet.

The pellet remains there for hours until the owl regurgitates it, pushing it back up the esophagus and into the mouth for ejection.

Not all owls are nocturnal. Not all fly quietly. Not all have asymmetrical ears. Not all mate for life. Not all roost in forest trees.