Batman in the wind

Not only Drosophila manage to fly at constant speed – bats maintain their groundspeed even when wind conditions change.

Livingstone's fruit bat  By Ben Charles via Wikimedia Commons
Livingstone’s fruit bat
By Ben Charles via Wikimedia Commons

When the winds change, bats adapt their speed of flight so that they manage to fly at constant speed. Researchers tracked fruit bats in Ghana on their way from roost to feeding sites, and correlated their flight speed with wind conditions. Contrary to fruitflies, fruit bats compensate for wind changes the way we would expect: with tailwind, they reduce their flight speed, and with headwind, they increase their airspeed. Flying at constant speed likely allows bats to reduce the cost of travel. They may easily measure the total distance travelled, navigate more easily according to landmarks, and reach their feeding sites without having to search widely at the destination. Bats, migratory birds and insects all similarly manage to fly at constant speed, even in changing wind conditions.

Original research paper in the Proceedings of the Royal Society B.