One of the more delightful oddities of nature is the musical mating practice of the mosquito. In order for such a romantic event to have a “happily ever after” ending, the male and female have to tune up and harmonize in the interval of a perfect fifth. The male sound is roughly a D (600 Hz) and the female a G (400 Hz). When they adjust their tones to create a perfectly tuned 5th, then the overtone of the 3rd can be heard (making the major triad) and mating will take place. A less talented and musical male, who can’t perfectly tune with the female, quickly becomes a rejected suitor. (A diminished 5th would be the death of the relationship!)
So maybe mankind should credit the mosquito love duet for the sound of the perfect fifth, the most euphonious interval in music history since the days of Gregorian chant. The perfect fifth is also the foundation of chordal harmony and the pivot point for tonality (which is always a pull between the tonic (first degree of the scale) and the dominant (5th degree). (All music students have heard of the infamous “Circle of Fifths” but never knew of its unsavory origins.) Maybe the history of Western music owes a debt of gratitude to the courtship duo of the pesky mosquito.
I couldn’t make this stuff up. Read the NPR article for yourself: “Mosquito Duet Leads to Love.”
Teaching Tip: Try this acoustic experiment in the classroom to understand the physics behind the mosquito love duet. Have 3 children twirl three Whistling and Listening Tubes at 3 different speeds. One will twirl slowly to create the tonic (first degree of the scale) representing the female mosquito, and the other twirl faster to create the dominant (5th degree of the scale) for the male mosquito. If the 3rd child can twirl even faster to get the next tone in the overtone series (the 3rd scale degree), you will hear a major chord, signaling the finale of the successful mosquito love duo.