Photo courtesy: Wikipedia
Ranger Rani is singing at the discovery. Alright, she is itching too. But, this discovery makes her sing. No, it isn't a duet.
Mosquito, we know are pests. They can bite us and make us itch and scratch like crazy. They've worked hard to earn their title, blood suckers. What about them that can make Ranger Rani sing?
Mosquito has a highly evolved neurosensory system. This enables a mosquito to receive a simple sound, the buzz of another mosquito and judge if the mosquito belongs to the same or different species. This comes from a species weighing no more than 5 milligrams. Imagine how small the brain size would be!
Before we jump into this mystery, we need to know something about the mosquitoes of the world. They are incredibly diverse with at least 3,500 known species. Yet, they all have one common trait. It is the whine.
While hovering to make a bite, the mosquitoes whine. That whine is a mystery to the scientists. Wonder why? After centuries of blood-feeding, shouldn't the mosquito have developed some quiet? Why didn't mosquitoes evolve a stealthy way to settle on the spot to fill their belly?
Scientists hypothesized that mosquitoes make the sounds to attract a mate of the right species. This need is far more important and required for survival. The risk of being squashed by the host is less important than extinction.
The genetics of the Anopheles gambiae mosquitoes is complex. It has considerable genetic diversity. The Anopheles gambiae is a complex of seven species and several chromosomal forms. This diversity is required to adapt to manmade habitat modifications.
Some genetic forms fly together in large swarms. To mate, they need to find the matching genetic diversity. It is like finding a needle in haystack. How do these mosquitoes find their matching species?
Scientists have discovered that when the wings of the mosquito beat, it creates the whine. This whine is music to the mosquito species. The male and female mosquitoes harmonize their wing beats with each other. The process is more like two partially deaf singers singing a duet. The singers can hear only low frequencies. They can't hear their own or each other's songs.
Instead, they listen to any disturbance in the harmony. If there's disturbance, the mosquitoes try to fine-tune, raise the pitch, and reduce the pitch. When the disturbance reduces to nothing, they have found a match!
Wonder how the scientists figured this out? At first they noted that mosquitoes of the same sex can't produce harmony in their music. The harmony also eludes if mosquitoes are of different species. Yet, the mosquitoes try to harmonize. The mosquitoes listen to the pitch and alter their own pitch. They listen to find out if they are singing in harmony. If not, they try to alter the speed of their wing beats. Like the wings of the humming bird, the different speeds of mosquito wing beats produce different whine. When all this doesn't work, the mosquitoes give up.
Ranger Rani, like the scientists is amazed. What requires a day's work in the lab, and extracting DNA to tell the species apart for humans, is actually a simple problem for the creature.
Even a creature like mosquito is capable of distinguishing individuals belonging to different species based on hearing, using an auditory input. This perfect adaptation helps mosquitoes survive in the wild.
Ranger Rani wonders if you will think about their song before you squash that mosquito next time!
