Nature – It Takes Nerves for Flies to Keep a Level Head

Researchers at Imperial College London have analyzed the nerve connections in the brains of flies that help them maintain a stable gaze during their rapid, complex aerial maneuvering, which in turn prevents them from colliding with obstacles in midflight.

According to an Imperial College press release, scientists have marked the connections between two key sets of nerve cells in a fly’s brain that help it process what it sees and fast-track that information to its muscles. This helps it stay agile and respond quickly to its environment while on the move.

The new research shows that the way in which two populations of nerve cells, or neurons, communicate with each other is the key. The lobula plate tangential cells receive input from a fly’s eyes, generating small electrical signals that inform the fly about how it is turning and moving during its aerial stunts. The signals pass on to the second group of neurons, which connect to the fly’s neck muscles and stabilize its head and thus its line of sight. By keeping a constant gaze even while its body changes direction, a fly is able to more efficiently process visual information and modify its movements accordingly.

Lead researcher, Dr. Holger Krapp, from Imperial’s Department of Bioengineering, says, “The pathway from visual signal to head movement is ingeniously designed: it uses information from both eyes, is direct, and does not require heavy computing power.” [Emphasis supplied.]

Krapp added, “Anyone who has watched one fly chasing another at incredibly high speed, without crashing or bumping into anything, can appreciate the high-end flight performance of these animals.

“They manage even though they see the world in poor definition: their version of the world is like a heavily pixelated photo compared with human vision. However, they do have one major advantage. They can update and process visual information more than ten times faster than humans, which is vital for an insect that relies on fast sensory feedback to maintain its agility.”

Dr. Krapp adds: “Keeping the head level and gaze steady is a fundamental task for all animals that rely on vision to help control their movements. Understanding the underlying principles in simple model systems like flies could give us useful leads on how more complex creatures achieve similar tasks.”

Just as a fly keeps a steady gaze during its rapid maneuvering, so must we maintain a stable gaze while moving quickly, with the eye directed ever upward, fixed upon the mark of our high calling in Christ Jesus, the Author and Perfector of our faith.

“Yield not to the power of the tempter. He will come as a strong man armed, but give him no advantage. Nerve yourselves for duty, and dispute every inch of ground. Instead of retreating, advance; instead of becoming weak and nerveless, brace yourselves for the conflict. … Put on the whole armor of God, and keep your eye steadily fixed on the Captain of your salvation; for there is danger ahead. …

“Soon the warfare will be over and the victory won.” Testimonies, vol. 5, 309.