Understanding Insect Brains

Understanding Insect Brains -Apple Fly
Apple Fly

One of the mysteries that concern farmers, medical researchers, and biologists alike is how bugs do what they do. How does the apple fly find the apple where it mates and lays its eggs that grow into apple maggots? How does a fly know when I lift a fly swatter that it needs to take off? How does that same fly find some food I left on the table? Scientists find a challenge in understanding insect brains.

The ordinary fly has 1/200,000 as many neurons as a human. But when robotics experts try to build a robot that can do what a fly can do using computer algorithms and bio-based solutions, they are spectacularly unsuccessful. Flying through three-dimensional space is especially difficult when ten meters is the farthest distance you can perceive visual information.

Research has shown that the common insect with wings, six legs, and several hundred lenses can solve problems in flight. They can locate objects of interest by combining sensory clues. Visual senses prevent them from running into things as they fly. Touch clues allow them to sense the wind. They have a sense of smell a million times more sensitive than what humans have. They use polarization patterns to help identify targets and temperatures ahead of them. According to leading entomologist Thomas Eisner of Cornell University, understanding insect brains requires us to “think like a fly.”

Remember that not running into things is only one concern an insect has. Avoiding enemies, mating, and recognizing an approaching object are also necessary skills. For example, apple maggots happen because the insect can identify color, shape, size, and odor to distinguish between an apple and a pear.

There are many reasons understanding insect brains is essential. For example, to avoid infestations of apple maggots without using harsh chemicals, we must understand the mechanisms of the apple fly and know how to defeat the process.

The skeptic will ask, “Why do these insects exist? Why did God allow apple maggots or the common housefly?” We must remember that insects are a staple in the food chain affecting many birds and mammals. Also, we must have living things that can process waste materials. Flies lay eggs that produce larvae called maggots that break down animal carcasses. Imagine a world where there were no processors of dead animals.

Thousands of years ago, God instructed the Israelites how to avoid most insect-carried diseases, such as by burying sewage instead of throwing it on the ground. Insects are a vital part of our world, and we could not exist without them. Managing resources intelligently is an essential part of human survival, and that requires understanding insect brains and how they work.

— John N. Clayton © 2021

Data from: “Insect Decision Making” by Shannon Olson and Pavan Kumar Kaushik, American Scientist, Volume 109, November/December 2021, pages 368-375.