• Some birds, like penguins, have lost the ability to fly but retained their wings.
• The smallest is the two-inch-long bee hummingbird.
• There are 5 types of finches in Pennsylvania.
• A woodpecker can peck twenty times a second and at speed of around 15mph.
• Birds do not have teeth and break their food on the outside and swallow it whole.
• Birds that eat berries get drunk on overripe fruit that's started to ferment.
• After habitat loss, outdoor cats are the number one cause of bird declines in North America.
• Birds have a third eyelid, a nictitating membrane, that they can actively control.
• Ravens are highly intelligent birds, capable of problem-solving and even using tools.
• Some birds lay their eggs in other birds' nests and have those birds raise their young.
• Birds can have symbiotic relationships with other animals.
• Birds sometimes sleep with one leg tucked up into their feathers to regulate their temperature.
• Birds use a wide range of vocalizations and body language to communicate with one another.
• Hummingbirds are the only birds that can fly backward.
• The peregrine falcon can dive as fast as 200 mph when hunting prey.
• The first bird domesticated by humans was the goose.
• Although an ostrich cannot fly, it can run up to 60 mph.
• Birds reproduce by internal fertilization and lay eggs with hard shells that hatch externally.
• Birds are some of the only creatures found on every continent of the world.
• Flamingos get their color from the food they eat.
• An albatross can sleep while it flies. It apparently dozes while cruising at 25 mph.
• The Archaeopteryx is the earliest known bird which lived approximately 147 million years ago.
• The fastest bird in level flight is the spine-tailed swift, which can reach speeds of up to 220 miles per hour.
• The White-breasted nuthatch hides seeds to eat during the winter when food is harder to find.
• Red-winged Blackbirds lay light blue-green eggs with dark markings that can be purple, black, or brown.
• The ruby-throated hummingbird flaps its wings 55 times every second.
• Mockingbirds often mimic other types of birds, but they have also been known to mimic frogs, people, and even car alarms.
• The European robin is known for its distinctive red breast and is a common symbol of Christmas in many European countries.