How do scientists connect genome to a brain circuitry through the behavior of songbirds

His explorations have involved improving genome assemblies, hunting for parallels between brain structures in different animal groups, and genetically manipulating birds and mice to sing better. Jarvis spearheaded a total rewrite of avian brain nomenclature, which has allowed scientists to better unravel the relationships between the brains of birds and vertebrates. He has led efforts to sequence dozens of bird genomes — something he’s now helping to do for thousands of vertebrate species as a co-chair of the Genome 10K Project — in order to construct accurate evolutionary histories. This work led to one of his major theories: that vocal learning arose independently in songbirds, humans and a handful of other animals when a far more ancient motor-learning pathway in the brain was duplicated.

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