Why don't mice fly like birds?

Bats actually fly very differently from birds. Quite differently - expending much more energy, they flap their wings differently, which perhaps explains their exceptional maneuverability. Swedish scientist Anders Hedenström from Lund University used a wind tunnel to look at the flight of these ancient mammals in detail. Artificial fog was added to the oncoming wind. This gave Hedenström the opportunity to see all the swirls and turbulence in the air created by the mouse's wings.

In some ways, bats have a much harder time than birds. The wings of the latter are flight feathers, which, when moving downwards, spread out, creating an airtight surface. When the bird's wing goes up, the feathers turn like slats of a blind and let air through. Chiropterans are different - they wave large leathery membranes stretched between modified fingers. In this case, the air resistance when raising the wings is stronger, and the mice have to work harder.

There is one more difference: if in birds the air turbulence created by the wings is combined into a single flow behind the flying animal, then in mice each limb creates its own small vortex. It is noted that from the point of view of aerodynamics, this style of flight is not very perfect (mice generally fly slower than birds), but in terms of maneuverability, bats are ahead of most birds. This allows you to easily dodge predators and chase randomly rushing insects.

In some ways, the style of movement of chiropterans is similar to the flight style of some insects. “This is the vertebrate version of the bumblebee,” Anders Hedenström told the British newspaper The Independent, “which is said to defy scientific logic because it is too heavy to fly with such short wings. Until now, it was unknown that bats are capable of creating such a large lift force with their wings.” The scientist also notes that bats manage to use even upward movements of their wings to fly. This requires a headwind, which creates additional lift for the animal’s wings. As Nature magazine notes, this is similar to how sailors use sails. Apparently, this refers to the ability of sailing ships to move on tacks, gradually moving against the wind.

Vladimir DZAGUTO