The scientists discovered that some 2,000 genes in a region of the male zebra finch's brain known as "Area X" are significantly linked to singing. More than 1,500 genes in this region, a critical part of the bird's song circuitry, are being reported for the first time. Previously, a group of scientists including the UCLA team had identified some 400 genes in Area X. All the genes' levels of expression change when the bird sings.
"We did not know before that all of these genes are regulated by singing," said Stephanie White, a UCLA associate professor of integrative biology and physiology and senior author of the new study. She believes the 2,000 genes -- at least some of which she believes are also shared by humans -- are likely important for human speech.