Much of the world knows that mosquitoes are nasty little creatures. What exactly do they do? Quite simply, they bite you and drink your blood without your permission! What’s more outrageous is that they always seem to be fond of your blood, and not of your friend’s, which infuriates you even more! Something should be done about this biased behavior, but what?
We’ve all swatted and smashed countless mosquitoes in our lives, but have you ever wondered how mosquitoes deal with other threats? More specifically, how do mosquitoes deal with rain?
For humans, dealing with the problem of rain is comparatively easy. If you’re outside and it starts to rain, you either run for cover with your hands over your head or simply pop an umbrella out of your bag. Mosquitoes are tiny creatures, however, so how do they behave when they’re hit by raindrops?
Mosquitoes Don’t Like Rainy Days
The reason for this natural dislike should be rather clear. Raindrops are not friendly to mosquitoes. It’s not the rain’s fault, but mosquitoes must hate raindrops with all their heart, because raindrops hurt them very badly. Good for us, not so much for them.
It’s all about the relativity of masses. A raindrop is almost as big as a mosquito (provided it’s anything more than a drizzle) and is denser that the mosquito itself. Water is heavier than the mosquito, so much so that the mass of a single raindrop can be almost 50 times the mass of a poor mosquito. It must hurt really bad to be hit by that chunk of mass when they’re flying around, looking for their next meal. Moreover, a raindrop can be really nasty if it hits the right (or unfortunate) spot, namely the space between the wings of the mosquito. To put it in terms that you might understand, a raindrop striking a mosquito would feel like a human who gets smacked by a school bus (assuming that a typical school bus has a mass roughly 50 times the mass of the person).
How Do Mosquitoes Deal With Raindrops?
Someone actually thought of finding out how mosquitoes deal with this situation. This particular researcher, David Hu, was actually a professor of Mechanical Engineering at Georgia Tech. He conducted an experiment back in 2012 using a high-speed camera with a frame rate of 4,000-6,000 frames per second (regular cameras shoot at 24 frames per second).
He observed the mosquitoes in ultra-slow motion and saw that most mosquitoes don’t need to dodge the raindrops, as most of the raindrops hit mosquitoes slightly off-center, on their legs, for example, and from there the drops are splattered out in six different directions, minimizing the effect of the drop’s impact on their body.
Raindrops do set mosquitoes rolling and pitching, however, much like a ship caught in a violent storm, but mosquitoes recover from the occasional dip amazingly quickly – in only one-hundredth of a second!
The Impact of Impact
Since a mosquito is a very small, light insect, it does not offer much resistance to the motion of the raindrop. The raindrop continues its motion on the back of the mosquito (if the drop hits it right between the wings) like a passenger on a vehicle. What happens is that the mosquito hurtles toward the ground at a very high speed and experiences an acceleration of very high magnitude. Thus, a very strong force of gravity acts on the mosquito’s body.
Hu said that a mosquito may experience up to 300 Gs when struck directly, and may still survive! According to Hu, “the mosquito is always able to laterally separate itself from the drop and recover its flight.” (Source) To put that into perspective, a pilot who feels 8 Gs at high altitudes and loops feels uncomfortable enough. Also, the highest ever G-force survived by a human is 214 G’s – Kenny Bräck (a race car driver) survived a nasty crash when his collided with that of a competing driver.
However, mosquitoes have harder heads than humans. We’re soft-skinned, unlike mosquitoes, who have exoskeletons. When a raindrop hits a mosquito right between the wings, it gets pushed towards the ground for a distance of nearly 20 times its own body. After that though, thanks to the water-repellent hair on its body, it quickly gets rid of the drop and resumes its normal flight. You can see this happen in the video of the experiment itself:
When all is said and done, if you’re a mosquito, my suggestion would be to stay as high above the ground as possible when it rains. That way, you won’t be hurt when those raindrops start falling.
- National Geographic
- Splish Splat? Why Raindrops Don’t Kill Mosquitoes – National Public Radio (NPR)
- Mosquitoes Don’t Let The Rain Get Them Down – Nature.com
- How Do Mosquitoes Fly in the Rain? – Smithsonian.com