From wolves to bees, all animals and insects depend on their capacity to locate the source of odors, which is difficult when wind disperses and hides their source. According to earlier studies, animals and insects find these targets by smelling the strength of the odors and then tracing back in the opposite direction of the wind.

For the same reason that smoke from a chimney disperses and its trail does not necessarily lead back to its source, following the wind alone, however, can misdirect them. Scientists at Yale University led by Thierry Emonet and Damon Clark questioned whether flies were capable of detecting the movements of odor packets without the aid of the wind.

The Emonet and Clark laboratories used their knowledge of motion detection and smell navigation to create experiments to test this theory for a new study. They found that, contrary to popular belief, flies are capable of detecting the motion of odor packets on their own, independent of the wind.

The researchers genetically altered the fly antennae to sense light in order to accomplish this finding. They then made fictive odor packets out of light and observed how the flies reacted to these signals in both windless and windy conditions. They discovered that the fly antennae worked to detect the motion of odor packets, enabling flies to change their route solely based on signals from odor packets. The article was released in the journal Nature on November 9.

According to the researchers, this information will help not just public health (how mosquitoes seek people) and agriculture (how bees locate flowers), but also the creation of robots that can detect threats like landmines.

Sources:

Nirag Kadakia et al. (2022). Odor motion sensing enhances navigation of complex plumes, Nature. DOI: 10.1038/s41586-022-05423-4

https://phys.org/news/2022-11-flies-motion-odors.html