Migrating butterflies has been a part of science mystery for years now, but perhaps finally there will be some light shed on the subject.
Monarch butterflies have been migrating from extreme northern portions of Canada, all the way down to Mexico for millions of years. While populations have heavily decreased, and some species have stopped migrating south – the underlying cause for this migration may have finally been identified.
Scientists studying the genome of the monarch butterfly found that there were two specific types of butterflies. First, the type of monarch that does not migrate, and the other that migrates. It’s an interesting topic because still today, even as populations dwindle; the North American monarch butterflies were found to have continued migrating.
Monarchs from outside the confines of North America do not. However, that isn’t nearly as interesting as the gene that was actually identified for being responsible for this travel. The journey is 3,000 miles, and for creatures that live only a matter of months – a 3,000 mile journey is an investment.
So, they must do it for good reason, right?
The scientists discovered that the monarch butterflies that do migrate have a gene that is similar to a distance runner, while the monarchs that do not have a gene that would be similar to a sprinter.
The ability to fly is guaranteed. However, the ability to fly thousands of miles, does not come naturally to all monarch butterflies. This study is interesting because it points to significant gaps in genealogy between two creatures of the same species. Ironically enough, the gene in question is actually the same gene that is responsible for the orange and black coloring we see on these monarch butterflies.
In the butterflies that fly further, and migrate are thought to be the most efficient of fliers, and that’s what the gene is creating. It’s responsible for bringing an efficiency to the butterflies, and at the opposite end of the spectrum, you have the power fliers, or the butterflies that don’t migrate – but are built for more powerful flight.
Right now it’s not clear which is more effective, or which is better for the species as a whole – or why certain members are gifted with one type of flight versus another. But, this is definitely a place for further research to start – and it’s clear that this is a point of emphasis for scientists as monarch butterfly populations continue to dwindle down.
In 1996 1 billion butterflies migrated to Mexico. This past winter, the numbers had so steeply dropped that it would almost become jaw-dropping, with just 35 million making the journey.