SoylentNews is people
SoylentNews
Common wisdom is that mosquitoes use multiple methods to home in on their prey, including Carbon Dioxide in respiration and detection of body heat. Now, in a paper published in the journal Science, researchers describe the underlying temperature detection mechanism used, and interestingly it isn't a heat-seeking mechanism, but rather a cold-avoiding one.
[...] Last year, [professor of biology Paul Garrity, Ph.D.] and several colleagues published a paper in the journal Neuron that upended the conventional thinking about the temperature-sensing receptors at the tip of flies' antennas.
Traditionally, these receptors were thought to act like thermometers, taking the temperature of the surroundings to let the fly know if the environment is hot or cold. Instead, Garrity and his colleagues found that the receptors only detected whether the temperature was changing, letting the fly know if things were getting hotter or colder.
For this reason, Garrity renamed these temperature sensors the Cooling Cells and Heating Cells. They're so sensitive they can detect a few hundredths of a degree change in temperature per second.
Mosquitoes, who are close evolutionary relatives of flies, also have Cooling Cells and Heating Cells.
While it would seem to make sense to look at the insects' heating cells to understand what draws them to human warmth, Garrity's group considered an alternative —- and counterintuitive —- hypothesis. Maybe it wasn't that the insects were flying toward the heat; maybe they were flying away from the cold. This would mean the Cooling Cells would be the ones to focus on.
The specific Cooling Cells Garrity and his fellow scientists studied for their paper in Science rely on a molecular receptor called IR21a. IR stands for ionotropic receptor, a group of proteins that help neurons to transmit signals. IR21a facilitates the transmission of a signal that the temperature around the insect is falling.
Here is a YouTube video comparing the ability of mosquitoes with and without the IR21a receptor to find a human temperature surface.
According to Garrity, the IR21a receptor is activated whenever mosquitoes move toward a cooler temperature. Since humans are usually warmer than their surroundings, this means that as a mosquito is approaching a human, IR21a is silent. But if the animal should deviate from its course and start to move away from its warm-blooded prey, IR21a becomes activated, only shutting off once the insect course-corrects.
Garrity said IR21a seems to act like "an annoying alarm. It goes off whenever the female mosquito heads towards cooler climes. When they are seeking humans, they seem to be driven to do whatever it takes to turn down the sound."
Also at Ars Technica and EurekAlert.
Now let's figure out how to hit 'snooze'.
Journal References:
Mosquito heat seeking is driven by an ancestral cooling receptor [$], Science (DOI: 10 .1126/science.aay9847)
In the heat of the night [$], Science (DOI: 10.1126/science.aba4484)
(Score: 2) by c0lo on Sunday February 09 2020, @10:35PM (8 children)
I wouldn't discount the mosquitoes "heat sensors" as yet.
If a warmer object is in the same room, will mosquitoes leave me alone and pick the warmer object?
If true, how come the entire humanity didn't notice this over its entire history, small candles were not that unusual [pinimg.com]
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 2) by Joe Desertrat on Sunday February 09 2020, @11:11PM (7 children)
Mosquitoes seem split between seeking food and avoiding danger. Cold, while not an attack, slows their metabolism making them less capable of both detecting prey and avoiding predators. To reinforce this, prey is more likely to be found in warmer areas, for much the same reason.
I believe the concentration of carbon dioxide around vertebrates is what helps them zero in, not the warmth. That is how they manage to find and attack prey such as reptiles, even though they are cold blooded.
I've noticed that a mosquito moving in on an "attack" will engage in immediate escape maneuvers if you swipe at them and miss. Depending on the direction of the swipe and the makeup of the surrounding area, they can make their escape away in any direction, usually towards a dark area. I've found that a better weapon than swiping (though it is satisfying to nab one of the devils in mid air) is to shoot them down with a spray of some sort. I don't mean insecticide, while that obviously works you don't necessarily want to be spraying it all over the place. Any household cleaning spray will "shoot them down", and if you follow the fall you can be sure of dispatching them where they land.
(Score: 2) by c0lo on Sunday February 09 2020, @11:50PM (2 children)
Laser zapping mosquitoes in slomo [youtube.com] - more humane and geekish.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 1) by Guppy on Monday February 10 2020, @07:02PM (1 child)
Eh, it's an Intellectual Ventures product, and they're well-known as a patent troll that can't actually produce anything.
Don't hold your breath waiting, that video you posted is already almost a decade old.
(Score: 2) by c0lo on Monday February 10 2020, @10:14PM
Doesn't mean the idea of laser zapping mosquitoes is not cool, no matter the source of it.
Install their "mosquito fence" in my bedroom? That would be idiotic, the "for bedroom" context offers lots of opportunities for simplification of the product - no need for weather proofing, insect species identification (it's a flying insect? Zap it, I don't keep any as pets), the power socket is readily available, etc.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 0) by Anonymous Coward on Sunday February 09 2020, @11:56PM (1 child)
> Any household cleaning spray
Have you tried water in a re-purposed spray bottle? I hate to spray cleaning products all around (although I agree they could be less annoying than insecticides).
(Score: 2) by hendrikboom on Monday February 10 2020, @06:14PM
Where do they hide out when it rains?
(Score: 2) by Freeman on Monday February 10 2020, @04:17PM (1 child)
I assume the "Bug Assault" salt guns would work on mosquitoes too. Though, It might seem a bit odd to be carrying around a black and yellow toy gun everywhere you go.
Joshua 1:9 "Be strong and of a good courage; be not afraid, neither be thou dismayed: for the Lord thy God is with thee"
(Score: 0) by Anonymous Coward on Monday February 10 2020, @04:31PM
Those things have a lot of bad reviews for quality issues.
What I want is a mosquito zapping laser tower. 360 degree protection for at least a 15 foot radius.