You set out to observe the symbiotic relationship between a species of orchid and a species of fly. This species of orchid is only pollinated by this one species of fly, and the flies seem to prefer that orchid over any other flower for its nectar supply. Identify and describe two reasons for the proximate causation for the species-specific preference of this fly. Select one of the reasons and make a prediction on the outcome on species-specific preference of the fly. Justify your prediction with evidence.