Come fall, monarch butterflies feel the need for a change in latitude. A new study shows that changes in the activity of a suite of genes in the butterflies’ brains help the insects find their way to overwintering grounds in Mexico.
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Steven Reppert, a neurobiologist from the University of Massachusetts Medical School in Worcester, leads a team of scientists on a mission to uncover the monarch’s migratory signals. The team describes a new genetic analysis of stationary summer monarchs and fall migratory monarchs in the March 31 BMC Biology.
At least 40 genes are involved in keeping the monarchs Mexico-bound once they start migrating, the researchers report. Reppert and his colleagues analyzed 9,000 of the monarch butterfly’s genes, about half of the genes in its genome.