One of nature's least complex creatures could help researchers understand some of nature's most complex behaviors.

Neuroscientists at the Howard Hughes Medical Institute are using thermogenetics — a technique that controls neurons using heat — to help understand the neural circuits responsible for complicated behavior such as courtship. The research includes triggering mating impulses in flies, Nature reports.

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Barry Dickson and his team were able to make flies "fall in love" with a ball of wax using the Fly Mind-Altering Device (FlyMAD). The device tracked the flies with a video camera while they flew around a box, targeting them with an infrared laser that delivered heat to their heads. The researchers also targeted neurons associated with muscle coordination, which made the flies walk backward.

Prior research has found that TRPA1, a heat-activated protein, is in part responsible for behaviors such as mating and decision-making in flies. When the protein is added to neurons associated with specific tasks, they can be controlled when triggered with heat.

Targeted with a laser in the current research, the modified flies displayed mating rituals directed at the wax, circling the object and vibrating its wings. After the laser was shut off, the behavior continued for another 15 minutes, implying that it was the heat that caused the attraction.

Dickson told Nature that optogenetics, a similar technique that controls neurons with light, proved successful with mice, but has not been tested on flies. The process required that a fiber-optic cable be embedded into a mouse's brain — something that isn't possible on a creature as small as a fly.

Future research could include testing the TRPA1 method in conjunction with one that uses channelrhodopsin, a light-activated protein. The FlyMAD research was presented at a conference in October and has been submitted for publication in a peer-reviewed journal.