“Idiosyncratic Learning Performance in Flies”, Matthew A.-Y. Smith, Kyle S. Honegger, Glenn Turner, Benjamin de Bivort2022-02-02 (; similar)⁠:

[“non-shared environment” ≈ randomness] Individuals vary in their innate behaviors, even when they have the same genome and have been reared in the same environment. The extent of individuality in plastic behaviors, like learning, is less well characterized. Also unknown is the extent to which intra-genotypic differences in learning generalize: if an individual performs well in one assay, will it perform well in other assays?

We investigated this using the fruit fly Drosophila melanogaster, an organism long-used to study the mechanistic basis of learning and memory. We found that isogenic [clonal] flies, reared in identical laboratory conditions, and subject to classical conditioning that associated odorants with electric shock, exhibit clear individuality in their learning responses.

Flies that performed well when an odour was paired with shock tended to perform well when the odour was paired with bitter taste or when other odours were paired with shock. Thus, individuality in learning performance appears to be prominent in isogenic animals reared identically, and individual differences in learning performance generalize across some aversive sensory modalities.

Establishing these results in flies opens up the possibility of studying the genetic and neural circuit basis of individual differences in learning in a highly suitable model organism.

[Keywords: Drosophila, generalized learning, personality, Pavlovian conditioning, individuality]