Wolves also have a complex communication system of using body language. The use of body language are in postures, movements of their head, and erect tail or a folded tail, and direct eye contact. All have great meanings. The postures are often subtle, but each wolf learns over time from when they are pups to read and respond to these postures and expressions. The facial expressions of the wolves are varied and useful in conveying moods or feelings to other members of the pack. Visualizations are a big part of the communication process to the wolves.