Before learning to speak, human babies go through a vocal stage known as babbling, which is a well documented part of the vocal language acquisition process. Basically, babbling is how an animal ...

Hopkin: Even sweeter are the sounds they make when they’re just beginning to explore their vocal capabilities. [CLIP: Baby babbling] Hopkin: But human babies are not unique—at least when it comes to ...

A green-rumpled parrotlet widow and her nestlings. The behavior of the nestlings — spilling out of the cavity begging for food — indicates that they aren't getting enough food. A team of University of ...