The effect of the detailed synaptic connectivity among neurons in a neural circuit on its function and the behavior of the organism, is a key question in many neural systems. C. elegans presents us with a particularly accessible system to explore these relations, thanks to its relative simplicity, the reconstruction of its connectome, and the range of molecular, imaging, and behavioral tools for studying it. We studied here the important circuit for nociception that is composed of the same set of neurons in the two sexes of C. elegans, which are connected in a sexually-dimorphic topology. As the two sexes demonstrate dimorphic behavioral response to aversive stimuli, we asked whether the distinct topologies are sufficient to explain these differences. We first showed, experimentally, that the sensory transduction is similar in the two sexes, and then explored the potential role of network connectivity as the source of behavioral dimorphism – by simulating the dynamics of the nociceptive circuits to external stimuli. As the biophysical parameters of these circuits are not known, we explored a wide range of realistic values for these parameters, and found the parameter sets that replicated the respective behavior of each sex. The number of overlapping parameter sets for the two sexes was relatively small, and, importantly – reproduced the behavioral differences observed experimentally. We then used our simulated model to identify critical potential rewiring of the networks that would switch behavior between sexes. Our model predictions were validated experimentally, where we showed that the male’s network could be rewired to generate the responses of the opposite sex, and in finding that the hermaphrodite’s network is more robust to perturbations. We thus suggest that sexual identity sculpts neuronal circuits for the sex-specific needs of the organism and present an example of behavioral reprogramming by simple connectomic editing.