Bumblebees have long posed a tricky problem to scientists. Why would these little buzzers have the boffins puzzled you might wonder? Well, the answer is that they had the academics baffled by appearing to defy the laws of physics.
It was declared that bumblebees should not be able to fly! The size and weight of their bodies versus the size of their wings meant that it was impossible. Clearly, the bumblebees didn’t know this, because despite our academic protestations – they most certainly could fly – and how!
So, have we managed to solve this mystery? Well, yes – but only as recently as the early 21st century have we been able to begin to figure out the bumblebees’ aeronautical secret.
If you measure the size and weight of the bee’s body and then the size of her wings, theoretically she shouldn’t be able to generate enough lift to be able to fly…. maybe the laws of physics were flawed? (Undoubtedly they are, but that wasn’t the answer in this case…)
It was only the advent of more sophisticated photographic techniques (and the help of some robotic models believe it or not!) – which gave us the ability to capture super slow-mo footage at thousands of frames per second, resulting in the conundrum of the bumblebees’ flight finally being revealed.
The footage showed the bumblebees were not just flapping their wings up and down as was previously thought – instead they were tilting their wings at an angle on the upstroke, cutting into the air and reversing the tilt on the downstroke. This generates lift on both strokes by creating mini vortexes which send the bee up, up and away. This technique, coupled with the ability to flap their wings at an incredible 230 times per second (wow!) results in – well bumblebees flying!
Further investigations revealed that bees have another trick up their sleeve (well thorax!) They have strong thoracic muscles running both horizontally and vertically and they use these to power their wings – the difference here from other flyers is that the muscles are independent from the wings. The whole process, like our own breathing for example, is autonomous (ie the brain controls it automatically) so the bees don’t have to give it any thought whatsoever!
If, like me, you find this fascinating … well… there’s more.. because the bees can also control the amount of energy they use for flying!
So, if they’re happily setting off for a day’s foraging in the flowers, they can put the pedal to the metal, as they are light and have nothing to carry. Once they’ve had their floral fill-up and are laden with booty, then they can spread out their energy in a more economical way, by modifying their wing technique and by slightly reducing the number of flaps per second. These economies help them get their full payloads back home safe and sound.
Speaking of heavy loads, did you know that bumblebees are the weight lifters of the bee world? They’re very strong and can carry up to 80% of their own body weight! Flex those muscles girls!
Bumblebees need a certain body temperature to be able to maintain flight – so what happens if they suddenly get a bit too chilly? Well, they take a rest and disengage their muscles from their wings, using them to shiver instead, in the hope this generates enough warmth to allow them to take off once more. Once they’ve managed to warm up again, they reengage those babies and they’re zooming high once more. So, if you see a bee that appears to be resting, this could be what she’s at.
Of course, we couldn’t forget to mention the bumblebee’s buzz. Where does it come from (really)?l Is it that the bees just like buzzing? Well not quite – that rapid wing flapping makes the buzzing sound and the vibrations from that help to dislodge pollen from the flowers, which then sticks to the bee’s hairy body – so they really get a buzz from cleaning up! (more than I do!!) Maybe that’s why sometimes bees seem to buzz a little louder? (Although I prefer to think it’s because they’re happy and enjoying themselves!)
Finally, we are beginning to unravel the mysteries around the flight of the bumblebee (probably much to the bee’s amusement that it’s taken us so long to cotton on – personally, I reckon they’ve enjoyed beefuddling us (!!) – they get a buzz out of it (!!)