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Behavioral differences can be observed between species or populations (variation) or between individuals in a genetically similar population (variability). Here, we investigate genetic differences as a possible source of variation and variability in Drosophila grooming. Drosophila grooming behavior confers survival and social benefits. Although the leg movements that constitute the grooming sequence are stereotyped, their order is not fixed. Grooming features of five drosophilid species exposed to a dust irritant were analyzed. Components of grooming behavior were conserved between and within species. However, significant differences in grooming syntax were identified, corresponding both to anterior and posterior grooming actions. Genetic heterogeneity was not found to be related to grooming variability, as melanogaster flies bred to increase genetic het-erogeneity did not exhibit increased variability in grooming syntax. Likewise, no relationship between decreased heterogeneity and variability was identified. Finally, individual melanogaster flies were observed on consecutive days to determine the degree of variability of grooming behavior within an individual over time. Individual flies were not found to possess strong, stable grooming traits over several recordings. Additionally, standardization of sensory input using optogenetics did not eliminate grooming variability. In aggregate, these data suggest the importance of sensory inputs and other factors such as life history in grooming variability. Significance Statement Broadly speaking, genes influence behavior, but genes also play a role in determining the natural range of behavioral variability. Here, we show that Drosophila species exhibit differences in grooming behavior both between and within species. In particular, we demonstrate that transitions between grooming actions differ significantly between drosophilid species and common melanogaster stock lines, suggesting that these actions are under partial genetic control. Within melanogaster, however, genotype had no observable effect on the range of grooming behavior. This work establishes similarities in grooming behavior between drosophilids while also highlighting important differences, providing targets for future explorations of genetic, sensory, and developmental contributions to behavior.