Monarch Butterflies Migrate Using 'Internal Compass' Steve Connor - The Independent
go to original April 10, 2013

The butterflies were tethered inside a flight simulator to a computer that detected their average compass direction over 15 minutes. (Ryan Norris/University of Guelph)

The North American monarch butterfly’s amazing migration, travelling thousands of miles each year from its wintering grounds in Mexico to as far north as the Great Lakes of Canada and back, is done without any internal maps, a study has found.

Scientists have shown that the annual migration of the monarch butterfly is achieved with just an in-built “compass” – based on the position of the sun – which tells the insect which direction it should fly at the appropriate time of the year.

Researchers have long speculated on how the insect, which weighs about half a gram, is able to make the return journey to the mountain forests of Mexico for winter, especially as those born in late summer, would not have made the journey before.

Experts thought they used an internal, genetically encoded “map” to locate their position, as well as a built-in compass to tell them where to fly. But now a study has shown that the butterflies manage with just a compass alone.

Read the rest at The Independent

We invite you to add your charity or supporting organizations' news stories and coming events to PVAngels so we can share them with the world. Do it now!