Changes in olfactory preference index for adult crickets (Acheta domesticus) conditioned to associate a favorable vanilla olfactory scent with one of five necromone cues: all-female cricket body extract (F Ex), all-male extract (M Ex), combined male-female extract (MF Ex), oleic acid (OA), and linoleic acid (LA). In the control treatment, crickets were conditioned with ethanol instead of a necromone cue. Positive indices indicate vanilla preference and negative indices indicate peppermint preference. A significant change in preference index between initial and post-conditioning tests (relative to the control) indicates learning associated with a necromone cue (* p < 0.05, ** p < 0.01). All preference indices were derived from perching durations (i.e. total time spent attending to either the vanilla or peppermint cue during the preference test). Bars indicate standard error.