Monarka butterflies find the way thanks to the biological clock

2003/07/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria

• Biologia

In autumn, monarch butterflies leave the north of the United States and Canada and head towards the Mexican jungles to spend the winter and reproduce in spring. The cycle of four thousand kilometers of travel is completed every four or five generations, that is, the butterflies heading towards Mexico are heading towards an unknown place, but are not lost on the road.

The researchers are almost convinced that they use the sun to know the direction, but they do not know how they adjust each day that direction as they change the position of the sun. Researchers believe the secret is in the genes that regulate the biological clock and have done tests to check the hypothesis at the Massachusetts Medical School.

Butterflies have entered flight simulators designed specifically and have played with light/dark cycles, until butterflies have adapted the biological clock to these cycles. In addition, they have followed the period gene that is expressed more or less depending on sunlight. The results have been striking: when leaving the simulator, only the butterflies that had been under a regular solar cycle left in the right direction.