Humans, unless aided with oxygen mask find difficulty in going to higher altitudes. Even a slight increase in altitude causes breathing related problem in humans. But unlike humans, birds are very well adapted to fly high without any problem. And recently it has been found that apart from birds, even bumblebees are capable of flying at great high. Wondering how high- higher than Mount Everest, which measure 8,848 meters (29,029 feet) above sea level.
A team of scientists from the University of California, Berkeley reports that alpine bumblebees have significant aerodynamic reserves and can fly higher than 9,000 meters (29,500) feet. Scientists are aware that the bumblebees cannot survive the freezing surroundings of Mt. Everest. And so they reproduced the conditions of low oxygen and low air density, that are found at such great heights to check bumblebees capacity to sustain in such conditions. And were surprised to see that bumblebees were capable of flying even under adverse conditions and elevations.
The team went to western China to collect six male bumblebees (Bombus impetuosus) at an elevation of about 10,660 feet (3,250 meters). These alpine species are not distinct from the one found near to the sea. These collected bees were then placed in transparent, sealed boxes. Scientists using a pump, regulated the oxygen levels and air density of the box to mimic the conditions found at high elevations. The temperature of the boxes remained constant.
The experiment showed that the bees are capable of flying in conditions similar to that found at 13,000 feet. And some of them could fly even beyond, as high as 30,000 feet (9,000 m) which is almost the height of Mt. Everest.
The scientists recorded the experiment and studied the pattern of the beating of wings and found that bees changed the angle at which the wings with every beat, rather than beating the wings more quickly to increase speed and energy. The increase in the angle of the wings with every beat, they reach closer to their abdomen and heads and thus increasing the amount of air they swooped, rendering them sturdy in the air.
The research thus concludes that the bumblebees are not limited by the their flying capacity, when looking for an ideal place to build their colonies, rather other factors such as availability of nectar and flowers limit their movement. The scientists are not sure whether bees living at lower heights are also capable of showing similar results in simulated conditions or bumblebees are specifically adapted to such conditions. Moreover, in the future helicopters might be designed keeping the findings of the research in mind as rescue at high elevation is still a challenge.