It is well known that insects have far fewer cells than their larger mammalian counterparts and this applies to the insect brain as well. The relationship between brain capability and brain size is an area of debate and some importance. The best correlate of brain size is the size of the animal. Larger animals have larger brains. However, for many animals, the larger brain may be a reflection of the larger numbers of muscles that must be controlled rather than an increase in ability to process information. Scientists are asking, “What is the minimal number of brain cells required for a process?”
If the smaller insect brain with fewer brain cells can accomplish many of the same tasks as animals with larger brains, then insects may be a much better model for developing Artificial Intelligence that is simpler and requires less computing power. This idea is driving research into insect capabilities and how insects accomplish these tasks. The most fertile area of research has been the processing of visual information by insects and applying the simpler visual processing system to remotely guided aircraft and robots.
The model insect for much of the “brain” research on insects is the honey bee. Honey bees can count. Honey bee foragers have a symbolic language (waggle dance) they can use to communicate food locations. Honey bees can remember and learn to navigate based on color or patterns. Honey bees can orient by using landmarks to return to their hive.
Much of the brain research on honey bees is focused on the “mushroom body” region of the bee brain that is responsible for information processing and integration. It is known that honey bee behavior changes with the age of the honey bee. Older honey bee adults exhibit a wider variety and greater complexity of behaviors that they can accomplish. This increase in behavioral repertoire is accompanied by an increase in bee brain size and an increase in the size of the mushroom bodies.
Ethologists (people who study animal behavior) often use species comparisons to find correlates with behavior. Larger brains are correlated with social Hymenoptera compared to solitary Hymenoptera. This is not surprising because social bees and wasps must perform a wider variety of tasks than solitary bees and wasps. Parasitoid Hymenoptera that must locate specific insect prey have larger brains than plant feeding Hymenoptera.
Current theory suggests that parasitoids must process more information to successfully locate and exploit animal prey than their plant feeding relatives that only need to locate a suitable host plant. Expansion of the mushroom body area of the insect brain is the primary area is correlated with complex behavioral capabilities. This has increased the interest in this area of the insect brain to further examine the processing.
Ant brains contain about 250,000 neurons which is far fewer than the estimated 85 Billion 10,000,000 for a human brain. However, the ant still contains a network of 250,000 cells and that will take a lot of time to discover how that network processes information.
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I have a student studying ants and their brains. Your info was helpful but we think there may be a typo in the sentence about human brains. Can you clarify for us? We read in another source that human brains have about 100,000,000,000 neurons. A third said there are about 85,000,000,000. But we read here that ants have 250,000 brain cells and humans have 10,000,000.
Good catch. Consensus estimates are about 85 Billion neurons in the human brain. Your sources that estimate 85 or 100 Billion neurons are correct. The ant number, 250,000 is correct.
Since cells are of similar size, the number of cells that can fit in the head of an ant are orders of magnitude smaller than the number that would fit in a human head.