Friday, August 24, 2018
  Around Campus, Research

By Maria Elena Hernandez

RIO GRANDE VALLEY, TEXAS – UTRGV graduate student Caleb Arellano is reviewing thousands of hours of videos to study sibling interaction. Except he can’t understand what they’re saying.

The siblings he’s studying are green-rumped parrotlets, animal models used to research vocal babble.

“While it’s true most animals vocalize, only a few types learn their vocalizations … usually a juvenile listening to a tutor, usually a parent, listening to it, processing what the parent is vocalizing inside their head and then trying to imitate it and attenuating that imitation until they get it just right,” Arellano said.

“A really good example of animals that learn their vocalizations are, actually, human beings.”

You've probably witnessed the “ga-ga goo-goo” stage in babies.

Dr. Karl Berg, assistant professor in the UTRGV College of Sciences Department of Biology, says the vocal babbling stage gets very complex right before the first word of the native language articulated by the baby.

“And the complexity of the acoustic structure of the vocal babbling signals apparently can give you insights into cognitive development and how the child is going to do later in life.”

Berg was working in Venezuela at the site of the world’s longest ongoing study of any wild parrot populations, when he heard something unexpected in a nest. The nests are equipped with cameras and microphones for researchers to monitor the parrots.

Dr. Karl Berg
UTRGV researcher Dr. Karl Berg, assistant professor of biology in the College of Sciences, is studying green-rumped parrotlets in Venezuela to research vocal babbling. Berg wants to know if growing up with one or two siblings changes how this development phase manifests, as opposed to growing up with 11 brothers or sisters. His research is supported by a grant from the National Science Foundation to study sibling influences on vocal babbling and development. (UTRGV Photo by Veronica Gaona)

“The parents weren’t around, and it usually means the nestlings kind of are asleep, and they don’t do a whole lot,” he said.

But, when he put on headphones to listen in, “There was like this singing inside the nest. … So I got really excited when I saw that, because it was late in development, not unlike vocal babbling.”

The chicks vocalizing to each other was a chance to study a popular, but untested, hypothesis about how social bonds can influence early cognitive development.

Berg said, “We can ask, ‘Does growing up with one or two siblings change how you manifest cognitive behaviors later in life, as opposed to growing up with 11 brothers or sisters?’”

To help get the answers, the National Science Foundation has awarded Berg more than half a million dollars to study sibling influences on vocal babbling and development.

“We jumped at the opportunity to look at this in a natural population,” he said.

The recordings Arellano is reviewing, which National Geographic Society funded, are from the research site in Venezuela.

“He’s actually been working for several years with the video,” Berg said, “quantifying how the individuals interact with each other. We’re interested to see whether individuals interacting with more siblings are inclined to develop a richer vocal babbling repertoire.”

To learn about more research underway at the UTRGV Department of Biology, visit utrgv.edu/biology/research.

green-rumped parrotlets
These little green-rumped parrotlets are the subject of a study by UTRGV researcher Dr. Karl Berg, assistant professor of biology in the College of Sciences, who is researching vocal babbling. Berg was working in Venezuela at the site of the world’s longest ongoing study of any wild parrot populations. Because the parrotlets are in Venezuela, and Berg and graduate student Caleb Arellano are in Brownsville, they are viewing hundreds of hours of video of the parrotlets, shown here in their nests. (UTRGV Photo by Maria Elena Hernandez)



ABOUT UTRGV

The University of Texas Rio Grande Valley (UTRGV) was created by the Texas Legislature in 2013 as the first major public university of the 21st century in Texas. This transformative initiative provided the opportunity to expand educational opportunities in the Rio Grande Valley, including a new School of Medicine, and made it possible for residents of the region to benefit from the Permanent University Fund – a public endowment contributing support to the University of Texas System and other institutions.

UTRGV has campuses and off-campus research and teaching sites throughout the Rio Grande Valley including in Boca Chica Beach, Brownsville (formerly The University of Texas at Brownsville campus), Edinburg (formerly The University of Texas-Pan American campus), Harlingen, McAllen, Port Isabel, Rio Grande City, and South Padre Island. UTRGV, a comprehensive academic institution, enrolled its first class in the fall of 2015, and the School of Medicine welcomed its first class in the summer of 2016.