Why do hummingbirds hum? Because they forgot the words! Jokes aside, birds sing as a form of communication, just like human beings. According to Britannica Online, only about half of the world's species of birds are songbirds, but that's still over 4000 different types of birds that belong to this scientific group.
There are many reasons why a bird sings. Some sing to announce where their territory is and some sing to attract a mate. Maybe that's why people say they can hear birds singing when they are in love! Birds will also sing when they're talking to their young or to strengthen their bond with each other. All songbirds have a similar vocal organ known as the syrinx or “song box” which is located in their chest. When air is sent through its song box, this allows the bird to create sounds.
Birdsong isn't always lovely notes and sweet melodies. Some birds make short, unpleasant sounding squawks or caws. Like humans, not every bird can carry a tune. Can you? Let's hear it!