Karen Hopkins: this is Scientific Americanof science fast. My name is Karen Hopkins.
Small children say very gibberish, like my son was at the aquarium when he was 2 or 3 years old.
[CLIP: Toddler talking about fish]
infant: “They say Bul Bul. I think that person and this person say Bul Bul.”
Hopkins: The sounds they make when they are just beginning to explore their vocal abilities are even more fascinating.
[CLIP: Baby babbling]
Hopkins: But human babies aren’t anything special, at least not when it comes to this kind of articulation. Because a new study shows that parrot babies also bab before they leave the nest.Findings published in journals Proceedings of the Royal Society B: Biological Sciences.
Carl Berg: When human babies babble, they seem to string together a lot of sounds in ways they don’t understand. No identifiable context.
[CLIP: Baby human babbling]
Hopkins: Carl Berg is an Associate Professor of Biology at the University of Texas, Rio Grande Valley. A parrot’s chatter is really similar, he says.
Berg: The gibberish is a good descriptive text.
[CLIP: Parrotlet babbling]
Berg: They seem to mix everything together and seem to regurgitate everything they’ve ever heard.
Hopkins: Berg and his colleagues have been studying a species of parrot called the green parakeet in Venezuela.
Berg: We have been monitoring residents intensively. This year marks the 35th consecutive year.
Hopkins: The researchers installed a video camera inside the bird’s nest. But it took a while before they noticed baby parrots running during vocal warm-ups.
Berg: When we first started filming inside the nest cavity, we missed it at first because by the time the parents arrived all the action and all the interesting things seemed to be happening.
Hopkins: That causes the baby to start screaming for food. However, when the parents are away, the chicks take turns napping, grooming each other, and talking to themselves.
Berg: Other siblings are often asleep.
Hopkins: And it continues this squeaky squeal even after the brothers fly away from the coop, leaving the last little parakeet left in the nest.
Berg: I mean, they spend endless hours there alone, and they certainly seem bored, and we can see them babbling as well.
Hopkins: This snuggling chatter is a little different from adult conversation, a little bland, and very quiet.
[CLIP: Parrotlet babbling]
Berg: If you’re standing just a few feet from the nest, you probably won’t hear it.
Hopkins: On the other hand, the pace of mature calls is much faster…
[CLIP: Mature parrotlet call]
Hopkins: And generally noisier.
Berg: Parrots are known to be fussy and picky.
[CLIP: Pair of parrotlets dueting]
Hopkins: If you want to avoid attracting predators to your nest, it makes sense to keep your experimental vocalizations down to whispers. And it’s not just South American parrots that do it. Berg then discovered that baby parrots of another species in Mexico and southern Texas also bab, a study he plans to present at the annual meeting of the Ethological Society this summer.
[CLIP: Parrot babbling]
Hopkins: Now, as to what this babble is all about, Berg says it’s unlikely to be a form of social communication because birds often do it when no one else is listening.
Berg: To better explain what they do, they probably make certain phone calls so that they can better understand what they’re hearing by observing or listening to the adult’s interactions. You may be practicing and adjusting your methods.
Hopkins: So, in addition to the standard “feed me” calls, babies also make communicative calls, such as those used by adults to coordinate their movements, and alarm sounds, such as a parrot crowing when it finds a snake or hawk. emits Crying to protect the nest. But in the babbling, all these calls are simply jumbled together with no immediately identifiable purpose or context. It’s like a rehearsal when birds actually have a nest to defend, a behavior to adjust, and a predator to warn about.
Berg: So babbling is a hodgepodge, a salad, of all these different calls that are already in use or end up in more specific functional contexts.
Hopkins: Berg also found that the babbling parrot playlist could be activated by steroids.
Berg: By giving chicks a moderate dose of corticosterone twice daily for a week, we were able to show that corticosterone-treated chicks had a larger repertoire.
Hopkins: This makes sense, as stress hormones are key to regulating chick growth and maturation. Now, as to whether it’s beneficial to have a fuller songbook…
Berg: It is quite possible. The broad repertoire of songbirds has been shown to be advantageous in many ways related to reproduction.
Hopkins: Berg will continue to monitor his oldest feathered friends to see if the same holds true for parrots.
Berg: One way to find out is through continued long-term ecological monitoring. There, they capture nearly all individuals in the population and label them with a unique color band.
Hopkins: That way, Berg and his colleagues can assess whether parrots had the broadest vocabulary as babies.
Berg: Is there anyone who moves or shakes today’s parrot society…
Hopkins: At least it’s proven by breeding success, and it will make a cry.
[CLIP: Adult Green-rumped Parrotlet calls]
Hopkins: science fast Produced by Jeffery DelViscio, Tulika Bose and Kelso Harper. Subscribe to podcasts wherever you can and visit ScientificAmerican.com for the latest in-depth science news.
[Clip: Show theme music]
For Scientific American scientific, rapid, My name is Karen Hopkins.
