AsianScientist (Oct. 13, 2014) – A gene responsible for building muscle tissue in monarch butterflies is the key to their annual mass migration, according to a study from an international research team including scientists from the Chinese Academy of Sciences.
The University of Queensland’s Professor Myron Zalucki, an author on the study published in Nature, said the research uncovered the secrets of the monarch butterfly’s spectacular migratory behavior and distinct orange color.
“These results have prompted a revision of the evolutionary history of this species and provided a few surprises about the genes that are responsible for certain traits,” Prof. Zalucki said. “This work emphasizes the importance of further study into gene-environment interactions to help conservation efforts for declining species.”
The study traced the history of the monarch butterfly, Danaus plexippus, from its expansion at the end of the last glacial maximum 20,000 years ago to the current widespread decline. Each year a population of monarch butterflies migrate in great masses from southern Canada to Mexico, but numbers have fallen in recent years.
The team sequenced the genomes of 92 monarch specimens from around the world and nine specimens of other butterfly species.
“Our results suggest that the monarch butterfly originated in North America from a migratory ancestor and spread across the globe, with some populations maintaining migratory behavior and others becoming non-migratory,” Prof. Zalucki said.
A single gene, Collagen IV alpha-1, was identified as having a strong influence on migratory behaviour by building muscle tissue and making metabolism more efficient in the migratory monarch populations. The researchers also found that wing colour variation was decided by the myosin gene DPOGS206617, which has never before been connected with pigmentation in insects.
“One of the ongoing challenges in biology is to work out the contribution of genes and environment to the behavior and biology of animals,” Prof. Zalucki said. “We need a greater understanding of gene-environment interactions to extend our knowledge about the extraordinary evolutionary history of this iconic butterfly and other threatened species.”
Prof. Zalucki said the results showed how the monarch butterfly populations had evolved when introduced to new areas and how they might evolve when habitats change.
“We’re seeing drastic changes to landscapes which force populations to adapt, migrate or perish,” he said. “The famous mass migration of the monarch is under threat due to habitat changes and scarcity of milkweed host plants.”
The article can be found at: Zhan et al. (2014) The Genetics of Monarch Butterfly Migration and Warning Coloration.
—–
Source: University of Queensland; Photo: William Warby/Flickr/CC.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.
