Molecular Biology, Neuroscience
Dr. Jarvis is also an associate professor of neurobiology at Duke University Medical Center.
Molecular Mechanisms of Vocal Learning
Days before graduating from the High School of Performing Arts in New York City, Erich Jarvis was invited to audition for the Alvin Ailey American Dance Theater, a renowned African American modern dance company. Instead, he chose pipettes over pirouettes: "I also really loved science, and I thought I could have a bigger impact doing that."
He may well have been right. As a neurobiologist, now at Duke University, Jarvis has had a productive career studying molecular pathways in the brains of songbirds—his chosen window into the larger issues of how the brain controls complex behavior. Along the way, he has proposed bold theories about the evolution of vocal production and learning in birds and how it relates to the origins of human language. Against considerable resistance, Jarvis successfully lobbied for and helped organize a series of scientific meetings in which researchers made major revisions in the terminology used to describe avian brain organization relative to other vertebrates because he believed the old naming system was outdated and impeding progress in the field.
Jarvis grew up in difficult surroundings in Harlem. His family was poor to middle class and his parents were divorced, so he and his siblings were shuttled among various relatives. His father, a science and music enthusiast from whom Jarvis says he learned intellectual openness and creative thinking, suffered from mental illness that culminated in drug addiction, homelessness and, in 1988, his death in an apparently random murder.
Jarvis overcame these hardships and made the sometimes-rocky transition to the demanding world of top-drawer science. After graduation from Hunter College in New York City with a bachelor's degree—and six papers on bacterial molecular genetics in Rivka Rudner's lab—he did graduate and postdoctoral work in the Rockefeller University lab of Fernando Nottebohm, who pioneered research on the neurobiology of song-learning in birds as a model for understanding neural plasticity in the adult brain.
At Rockefeller, Jarvis devised a method he termed "behavioral molecular mapping" to determine how a bird's motor activities influence the resulting changes in gene expression in the brain. With this tool he has traced out the brain pathways for vocal learning in three distantly related birds—parrots, hummingbirds, and songbirds. Surprisingly, he found the pathways were strikingly alike. He concluded that vocal-learning mechanisms had evolved in three separate and independent events that must have been guided by strong genetic influences.
In fact, Jarvis and his colleagues suggest that human language ability is the result of a similar evolutionary journey. What birds and humans have in common, he notes, is a connection between the front part of the brain and nerves in the brainstem that control movement—namely, muscles for producing songs in birds and speech in humans.
Jarvis's lab is now trying to identify the evolutionary factors that permitted birds and humans to learn a variety of vocalizations. "My hypothesis is that it was for attracting mates," Jarvis says. "The more varied the sound an animal produces, the more likely it will attract the opposite sex."
Using his molecular mapping technique, Jarvis recently discovered that the brain centers for vocal learning in birds appear to have evolved from an ancient pathway involved in motor control. The design of the vocal-learning pathways may have followed this preexisting anatomical pathway, used to control the limbs for movement. In Jarvis's opinion, this means that learned singing is a highly specialized form of motor control, rather than a sign of high intelligence. Jarvis also recently co-led an international consortium to sequence the genomes of many species across all bird orders and used it to resolve the bird family tree, origins of vocal learning in birds, and convergent molecular changes in genes regulated in song learning brain areas of birds and speech brain areas of humans. The identified genes are candidates that develop and control vocal learning brain circuits in birds and humans.
As an HHMI investigator, the neurobiologist will test this hypothesis, using a variety of gene expression studies. He'll continue previous work in which he and his colleagues also identified a large cascade of genes that turn on rapidly when birds carry out learned behaviors. Perhaps, Jarvis suggests, he can discover the proteins involved in maintaining memories of songs and learning new ones. Ultimately, he hopes the research might have medical benefits, such as helping to restore speech in people who have suffered damage to the region of the brain that controls speech.
HHMI's philosophy fits Jarvis's scientific style perfectly. "It allows you to pursue your dreams and explore crazy ideas, without complaining that they're too ambitious or risky," he says. "To me, science is much more fun that way."