Though they perch far apart on the avian family tree, different groups of birds that can learn songs use similar brain structures to pitch their tunes.
The findings may also help solve the riddle of why humans (especially Italians) talk with our hands and voice, but chimps (except in the Planet of the Apes) can talk only with their hands.
"In its most specialised way, spoken language is the ability to control the learned movements of our larynx," neorobiologist Erich Jarvis said. "It's possible that human language pathways have also evolved in ways similar to these birds.
"Perhaps the evolution of vocal learning brain areas for birds and humans exploited a universal motor system that predates the split from the common ancestor of birds and mammals."
Professor Jarvis and his colleagues examined bird species with vocal learning skills and some without: garden warblers, zebra finches, budgerigars (an exceedingly cute species of parrot), Anna's hummingbirds and ring doves. The coneheads observed and manipulated bird behavior, then recorded which genes were active in the birds' brains when the birds moved and sang in certain ways.
While all birds vocalize, for most of them these sounds are genetically hardwired. Only parrots, songbirds and hummingbirds have the ability to learn songs. This type of vocal learning is similar to the way humans learn to speak, Professor Jarvis said.