Peripheral axonal pathway and cleaning behavior are correlated in Drosophila microchaetes.

The notum of Drosophila is covered with evenly spaced small mechanosensory bristles (microchaetes). Four groups of microchaetes can be distinguished on the basis of the pathways followed by the axons of their neurons. In three of the four groups, the axons extend along fibrous processes, the prospective tendons of the adult indirect flight muscles, formed by the epithelial cells. We show that the subdivision into four fasciculation groups is correlated to differences in the cleaning behavior elicited by stimulating the microchaetes.