What Makes Mosquitoes So Good at Avoiding Detection?

It sneaks up on you, inserts its needle-like proboscis into your skin, and loads up on blood. By the time you figure out that you’ve been bitten, the mosquito has made a stealthy getaway. How do they do it? University researchers in Berkeley, California, and the Netherlands used high-speed cameras to see how mosquitoes escape, even when weighed down by a belly full of blood. Observing Anopheles coluzzii mosquitoes, the scientists figured out the insects' modus operandi: They flap their wings for 30 milliseconds before jumping into the air. Then they beat their wings extremely quickly, as much as 800 times per second -- about four times faster than other flying insects.

Bearers of bad news:

• "They push off so softly that you can never detect them," says Florian Muijres, the study's lead author. "It's a very challenging thing to do."
• The study's results may be useful for managing mosquito-borne illnesses in the future. Mosquitoes can carry diseases like malaria, West Nile virus, and Zika.
• Mosquitoes are now a problem in Puerto Rico, where Hurricane Maria left behind pools of stagnant water that turned the U.S. territory into a mosquito paradise.

Frequently Asked Questions

How do mosquitoes manage to fly so quietly?

Mosquitoes have evolved to fly silently to avoid detection by their prey. Their wings beat at a frequency outside of most animals' hearing ranges, including humans. Additionally, the design of their wings and the patterns of their wingbeats minimize sound, making it challenging for potential victims to notice their approach.

What sensory adaptations do mosquitoes have for finding hosts?

Mosquitoes are equipped with highly sensitive receptors that allow them to detect carbon dioxide and body heat from potential hosts. They can sense CO2 from up to 50 meters away, which is a primary signal that a host is nearby. Their compound eyes are also adept at picking up movements, further aiding in their hunt.

Can mosquitoes detect repellents, and how do they react?

Yes, mosquitoes can detect repellents. Substances like DEET interfere with mosquitoes' olfactory receptors, making it difficult for them to locate a host. When a mosquito encounters a repellent, it typically avoids the area or lands less frequently, reducing the chances of a bite.

Why is it so hard to feel a mosquito when it lands on you?

Mosquitoes have evolved to be as unobtrusive as possible. Their lightweight bodies and delicate legs allow them to land softly without alerting their hosts. Furthermore, they inject saliva containing anticoagulants and mild painkillers into the bite area, which helps to mask their presence while they feed.

Do mosquitoes have a preference for certain types of hosts?

Mosquitoes do exhibit preferences for certain hosts. Factors such as blood type, body heat, carbon dioxide emission, and even the bacteria on the skin can influence a mosquito's choice. For instance, people with Type O blood are reportedly more attractive to mosquitoes than those with other blood types.

How have mosquitoes adapted to different environments to avoid detection?

Mosquitoes have adapted to a wide range of environments by developing behaviors and physical traits that help them remain undetected. For example, some species are active at dusk or dawn when visibility is low, while others have patterns on their bodies that provide camouflage against certain backgrounds, making it harder for both predators and prey to spot them.