Switching energy to safety, bees straighten their legs to firmly fly in the wind

New research shows that some bees self-balance themselves with the wind and other disturbances by stretching their sturdy rear legs while flying. But this seems to be "expensive", consuming aerodynamic traction and energy required for flying 30% more, and hindering the flight of bees.

The research results are presented in the Proceedings of the National Academy of Sciences.

'Wind is part of the life of all flying animals,' said Stacey Combes, professor of organizational and evolutionary biology at Harvard University. 'However, we still don't know much about how animals can balance in windy conditions and unexpected air currents, because most flying animal studies take place at The idealized environment, for example, is completely windless in space. Our work indicates that the impact of environmental disturbances on stability is a determinant but not yet recognized of flight activity. "

Combined with Robert Dudley of the University of California at Berkeley and the Smithsnian Tropical Research Institute, Combes explored 10 species of orchid bees or flew at high speed with dozens of kilometers of flight paths per day to get food and stuff. Other necessary. Males of these species particularly like to collect aromatic oils placed in bags on the hind legs, so that at some point they will use this smell as a way to attract female bees.

Some bees self-balance themselves with the wind and other disturbances by straightening their sturdy rear legs while flying.(Photo: iStockphoto / Roel Dillen)

Because males of orchid bees are too intense to scent, they are easy to fall into dangerous situations, such as when Combes and Dudley create a strong wind from Panamanian airplanes. where these bees live. With the use of high-speed video cameras, scientists have measured the maximum flight speed when these bees face varying degrees of unstable air conditions. In all cases, bees are moving from one side to the other at high speed, dealing with air turbulence by stretching the hind legs while flying.

'This way of increasing the moment of inertia of the bee's body and reducing the level of swaying in motion,' Combes said, 'is similar to an figure skater who is performing his arms twisting. out to balance. '

The sway is increasing as the flight speed increases until the bee's body is tilted to one side or the other at an angle of 80 degrees, in this position the bee will not hold and be stabbed to the ground. Or blow away from the air stream. Bees have the ability to reach higher speeds when in a quieter environment.

While Combes and Dudley only studied 10 types of euglossine bees, Combes argued that this balance seems to be common in all Hymenoptera species including bees, wasps, bee bites and ants. The turbulent flow of air can reduce the flight activity of many other flying insects.

The work of Combes and Dudley is funded by the Miller Basic Science Research Institute.

Refer:
Stacey A. Combes, Robert Dudley.Turbulence-driven instabilities limit insect flight performance.Proceedings of the National Academy of Sciences, 2009;DOI: 10.1073 / pnas.0902186106