Do Flies Have Cognition?
Doctor Josh Dubnau discusses some remarkably sophisticated behaviors in fruit flies that suggest that they do have cognition.
The question of whether flies have cognition depends a lot on what we mean by cognition. Fruit flies are remarkably sophisticated animals in the sense that they can court members of the opposite sex. They are able to find animals that are of the same species as they are, not a different fruit fly species but the same one, drosophila melanogaster courts drosophila melanogaster. Fruit flies are able to find appropriate food sources; they defend territory from other fruit flies. Theyâ€™ll fight over access to a place to lay eggs, they are able to figure out what time of day is the most appropriate time to sleep and what is the most appropriate time to forage for food, and they can learn from their past experiences about what stimuli were noxious, or what stimuli (what smells, what sounds or what colors) were associated with something that tasted bad or something that was pleasing. Whether or not that was cognition, Iâ€™ll leave that to the philosophers.
cognition, drosophila, melangoster fruit, fly, flies, josh, dubnau, cshl
Doctor Josh Dubnau explains that model systems are particular species of animals that substitute for humans or other animals. For genetic and historic reasons, the fruit fly is a commonly used model.
Many of the genes important for memory in flies are probably also important for memory in other animals, even humans. Doctor Josh Dubnau explains how the T-maze is used to test memory in flies.
Like all brains, insect brains have different structures that accomplish specific tasks. Dr. Josh Dubnau introduces a technique for examining gene expression in the brains of fruit flies.
Doctor Josh Dubnau describes how he and his colleagues at Cold Spring Harbor Laboratory devised an experiment that dissociated the encoding and retrieval of memory in fruit flies.
Doctor Josh Dubnau explains that the genes active in different neurons can make them excitatory (e.g. glutamate) or inhibitory (e.g. GABA). These neurotransmitters are critical to learning.
Early drawing of a male fruit fly.
The fruit fly is easy to maintain, has large numbers of offspring, and grows quickly. The fruit fly shares with humans a number of so-called “master,” or homeotic, genes.
The Fly Room at Columbia University, around 1920.
Doctor Josh Dubnau explains that mutant screens generate a large panel of mutant animals that average a mutation in one gene. Each animal is then tested for a particular characteristic.
Doctor Josh Dubnau explains that memories may be present (encoded) but not accessible (retrievable). Scientists have devised a number of experiments for teasing apart encoding from retrieval.