The flight of the humble bee was once so baffling that mathematicians famously concluded it was impossible. But using high-speed cameras and a scale model robot scientists have at last worked out the secret that helps bees stay aloft.
Most flying insects flap their wings using long, sweeping strokes, but honeybees take a less efficient approach. Even though it is a less stable way to fly, honeybees flap their wings more furiously producing just enough force to lift their bodies.
The scientists believe bees developed the unusual style to cope with the varying demands they face during flight. When foraging for nectar, they are at their lightest, but when laden with pollen, or carrying larvae, they can weigh twice as much. By switching from rapid, short wingbeats to longer beats, bees can vary the creature's lifting power considerably.
The scientists unravelled the bees' flying tactics by diverting them into a clear plastic box fitted with three high-speed video cameras which took 3D snapshots of the hovering insects 6,000 times a second. They found that a honeybee typically flaps its 1cm-long wings 240 times a second, each beat covering an arc of only 90o.
Other insects flap at no more than 200 times a second, with each stroke beating over a 165o arc. Instead of producing a steady, powerful upward thrust, the bees' flying style generates peaks of lift at the beginning, middle and end of each beat.
To test the bees, researchers pumped a mixture of helium and oxygen into the box, making the air thin. The bees responded by opening out their stroke to around 140o, and switching their flight behavior to that used by other insects.
Tens of thousands of Filipino Catholics yesterday twirled white cloths and chanted “Viva, viva,” as a centuries-old statue of Jesus Christ was paraded through the streets of Manila in the nation’s biggest annual religious event. The day-long procession began before dawn, with barefoot volunteers pulling the heavy carriage through narrow streets where the devout waited in hopes of touching the icon, believed to hold miraculous powers. Thousands of police were deployed to manage crowds that officials believe could number in the millions by the time the statue reaches its home in central Manila’s Quiapo church around midnight. More than 800 people had sought
DENIAL: Pyongyang said a South Korean drone filmed unspecified areas in a North Korean border town, but Seoul said it did not operate drones on the dates it cited North Korea’s military accused South Korea of flying drones across the border between the nations this week, yesterday warning that the South would face consequences for its “unpardonable hysteria.” Seoul quickly denied the accusation, but the development is likely to further dim prospects for its efforts to restore ties with Pyongyang. North Korean forces used special electronic warfare assets on Sunday to bring down a South Korean drone flying over North Korea’s border town. The drone was equipped with two cameras that filmed unspecified areas, the General Staff of the North Korean People’s Army said in a statement. South Korea infiltrated another drone
COMMUNIST ALIGNMENT: To Lam wants to combine party chief and state presidency roles, with the decision resting on the election of 200 new party delegates next week Communist Party of Vietnam General Secretary To Lam is seeking to combine his party role with the state presidency, officials said, in a move that would align Vietnam’s political structure more closely to China’s, where President Xi Jinping (習近平) heads the party and state. Next week about 1,600 delegates are to gather in Hanoi to commence a week-long communist party congress, held every five years to select new leaders and set policy goals for the single-party state. Lam, 68, bade for both top positions at a party meeting last month, seeking initial party approval ahead of the congress, three people briefed by
Cambodia’s government on Wednesday said that it had arrested and extradited to China a tycoon who has been accused of running a huge online scam operation. The Cambodian Ministry of the Interior said that Prince Holding Group chairman Chen Zhi (陳志) and two other Chinese citizens were arrested and extradited on Tuesday at the request of Chinese authorities. Chen formerly had dual nationality, but his Cambodian citizenship was revoked last month, the ministry said. US prosecutors in October last year brought conspiracy charges against Chen, alleging that he had been the mastermind behind a multinational cyberfraud network, used his other businesses to launder
RSS