For almost 70 years scientists and engineers have been mocked for being unable to explain how bees fly, but researchers at Caltech and the University of Nevada at Las Vegas have finally revealed the answer.
From the time that two French scholars declared in 1934 that bee flight was aerodynamically impossible, scientists have struggled to find out how the bees' small wings kept their fat bodies aloft.
High-speed digital photography and a giant robotic mock up of a bee wing have shown that bees use short choppy wing strokes, a rapid rotation of the wing as it flops over and reverses direction and a very fast wing beat frequency. Bees flap their wings uncharacteristically fast for their size, being an exception to the rule that the smaller the insect the faster it flaps its wings.
They also only flap their wings through an arc about half the size of that of other insects. To compensate for heavy loads, bees do not flap their wings faster but make them flap through a wider arc, which is not very aerodynamically efficient. One of the study authors, Prof Michael Dickinson, said, "Bees have evolved flight muscles that are physiologically very different from those of other insects.
One consequence is that the wings have to operate fast and at a constant frequency or the muscle doesn't generate enough power. This is one of those cases where you can make a mistake by looking at an animal and assuming it is perfectly adapted.
An alternate hypothesis is that bee ancestors inherited this kind of muscle and now present-day bees must live with its peculiarities." The research on how bees fly may well be extended into the creation of flying insect-sized robots in the future.