This is bird note.

Imagine you're about to shake hands, but with a sulfur-crested cockatoo.

Should you offer your right hand or your left?

You should hold out your left hand.

That's because most sulfur-crested cockatoos are left-footed.

In complex tasks like manipulating a piece of fruit, these intelligent birds work intently

with their feet. A parrot's eyes are located on the sides of its head. So if it wants to look at something,

say a delicious piece of fruit, it has got to cock its head one way or the other to do it.

And if it looks with its left eye, then it uses its left foot.

Scientists call this handedness. That's when one hand or foot is used consistently over the other for doing more complex tasks.

In a study of 16 Australian parrot species, scientists found that about half were lefties, a third were righties, and a few were neither.

Handedness, once thought unique to humans,

is also seen in chimps and gorillas,

mostly righties, and orangutans, mostly lefties,

as well as cats and kangaroos.

The evolution of handedness, for righties and lefties alike,

improves skill and efficiency in complex tasks

for both parrots and for humans.

For bird note, I'm Michael Stein.