Conversations of Marmoset monkeys are quite similar to the way humans speak. Researchers have found that these monkeys follow certain etiquette and take turns while talking with their mates, sometimes waiting minutes for their turn.

Marmosets are small, squirrel-like primates found in South America. They are considered to be the most primitive species of monkeys as lack the ability to even change their facial expressions.

These monkeys, however, are very friendly with each other and use vocal sounds to communicate.

For the study, the team kept marmosets in opposite corners of a room. The room was designed in such a way that the animals couldn't see the each other, but only hear their calls. Researchers found that marmosets didn't call out together, but waited for about 5 seconds after the other person had finished calling to respond.

"We were surprised by how reliably the marmoset monkeys exchanged their vocalizations in a cooperative manner, particularly since in most cases they were doing so with individuals that they were not pair-bonded with," said Asif Ghazanfar of Princeton University. "This makes what we found much more similar to human conversations and very different from the coordinated calling of animals such as birds, frogs, or crickets, which is linked to mating or territorial defense."

The new study provides a unique insight into the monkeys' behavior. Researchers said that the trait is probably exclusive to marmosets as other great apes "not only don't take turns when they vocalize, they don't seem to vocalize much at all, period!"

Also, the research helps understand the origins of conversation in humans and why some people develop communication disorders.

"We are currently exploring how very early life experiences in marmosets-including those in the womb and through to parent-infant vocal interactions-can illuminate what goes awry in human communication disorders," Ghazanfar said in a news release.

The study is published in the journal Current Biology.

Related research has shown that even rhesus monkeys know when to speak and when to stay silent. And, certain species of monkeys can understand basic forms of wealth.