Genes guide monarch butterflies to Mexico

Scientists have found a group of genes that may be involved in driving North America's monarch butterflies every fall toward the south. 

Researchers at the University of Massachusetts Medical School say 40 genes are responsible for the monarch's 4,000-km journey from Canada to Mexico. 

The study conducted by neurobiologist Steven Reppert and colleagues is the first of its kind focusing on the exact genes responsible for migratory behavior in animals. 

"Our data are the first to provide a link between gene expression profiles in the brain and migratory state in any animal that undergoes long-distance migration," ScienceDaily quoted Reppert as saying. 

The study found that the monarch uses an internal clock and a 'sun compass,' which senses the angle of the sun, to find its way south every fall. 

“Our results also provide the first insights into gene expression patterns that may underlie sun compass orientation, a complex process involving the integration of temporal and spatial information," explained Reppert.