[Marc Dantzker, Cornell Lab of Ornithology] Hi, I’m Marc Dantzker from the Cornell Lab of Ornithology. People love parrots. One of the main reasons is their ability to mimic things. What’s surprising is that until recently we’ve known almost nothing about how and why parrots learn and mimic sounds in the wild. That’s where Karl Berg comes in. Karl’s just finished his PhD at Cornell, studying the Green-rumped Parrotlet. He works in Venezuela, using nest box cameras, sort of like the ones we love to watch online. [Green-rumped Parrotlet] But before we get to Karl, I need to tell you two amazing things that researchers have figured out about wild parrots. The first is that as pets in our homes, they’ll mimic just about anything, including the sounds of other animal species, like humans and dogs and other birds. In the wild, they only make the sounds of their own species; they don’t mimic anything else that we can tell. The second, the second amazing thing about parrots is that parrots have names. Now, scientists call these names signature contact calls, but it’s fine to call them names. Lots of animal species have names, but what makes parrots so amazing is that they’re able to use, not only their own name, but other individuals’ names. So lots of animals can go, “Hey, I’m Bob, I’m Bob.” “I’m headed that way. I found some food. I’m Bob.” But what parrots can do is they can say, “Hey Tom, want to go get some food? I’m Bob.” And that’s pretty amazing, and it’s a real standout feature of parrot communication. Now back to Karl and his nest boxes in Venezuela. Karl set out to figure out how parrots get their names, where the names come from. Are they born with a name? Or is it learned through some kind of mimicry given to you from your parents or derived in the nest? The details of Karl’s experiment are a little bit like switching babies in a hospital. He goes to two nests, takes the eggs out and swaps them.[Sounds like biological parent = genetic] If the babies grow up sounding a lot more like their biological parents, then we know the names are encoded in their genes. [Sounds like adopted parent = learned] If their names end up sounding more like the names of their adopted parents, then we know that those names were learned. Karl has cameras and microphones inside and outside of the two and records everything that happens in each of the nests for two months. These chicks are about two weeks old and at this point they’re making begging sounds, but they don’t have names of their own yet. But they are listening to their parents talk to each other and they’re learning to recognize those names. Okay, here comes Dad. “Hey kids, it’s Dad.” And now the mom arrives outside. You can see her tail flipping back and forth. She says, “Hey Dad, is that you down there?” “Yeah Mom, it’s me, Dad. Come on down.” And the chicks are hearing all of this. This interaction between the parents calling their names back and forth. Here we are a week later. These chicks are all sleeping. When they hear the sound of their own parents outside, they perk up. See, they open their eyes and they get active. In this moment we can actually see the chicks recognizing their parents’ names. And that’s, that’s a great example of them learning, recognizing, showing us that this environment of having names called back and forth has meaning to them. Four or five days later, the chicks are starting to make sounds that will become their names. But just like a human baby learning to talk, they don’t quite have it right yet. Now three weeks in, these six siblings each have a separate name. And they recognize and know their parents by this point and they’re probably beginning to recognize each other’s names. We’re at one-month now and the chicks are about to fledge, leave the nest and never come back. In fact, the bird on the right is about to fledge right here. It’s at this point that the chicks have a fully formed name and Karl records these calls. And using some pretty amazing software, compares them to the sounds of their biological parents and to the sounds of their adoptive parents. Oops, there she goes. What you find is that their names are most similar to the parents in the nest where they grew up. And what this proves is that those sounds are learned and not genetically encoded. This is the first ever actual demonstration that parrots learn in the wild. Pretty amazing given that it’s so clear that they learn in our houses. This signature contact call, this name, is only one of probably hundreds of sounds that parrots make. Karl’s work is a step towards understanding what may prove to be one of the few communication systems on earth that rivals our own for complexity.End of transcript
As pets, parrots mimic the sounds around them, including their human companions. But in the wild, they only make the sounds of their own species. Wild parrots address each other using “signature contact calls” much like using someone’s name to get their attention. Karl Berg asks the question, “How do parrots get their names?” The answer is that parrots learn their names while they’re in the nest. They hear their parents using each other’s names and begin calling themselves by names that sound similar, but not identical to those of their parents. Learn how watching baby parrots in their nests helps us unravel the mysteries of bird communication.