One of the most amazing displays of nature’s complexity is the migration of butterflies to their winter homes in Mexico. It’s simply mind-boggling to think of these seemingly fragile and delicate beauties possessing all of the energy and navigational mechanisms needed for hundreds of millions of them to make that trip.
One essential part of the flight control system is a biological clock – located in the butterflies’ antennae, not in their brains – according to a new study reported in Science magazine.
Migrating monarchs rely on the sun to maintain a constant heading. Because the sun drifts from east to west as the day wears on, the butterflies need a timekeeping device to help them compensate for its movement. Monarchs have a biological clock in their brains that relies on light cues to regulate their sleep-wake cycles and monitor day length. Scientists assumed they also used this clock to navigate.
But it turns out that the antennae possess a separate clock that controls time compensation, according to the new study by neurobiologists at the University of Massachusetts Medical School in Worcester.
God speed, butterflies!