section_path: Behavior
section_name: Behavior
paragraph_text: Behavior
  
  Although fear behavior varies from species to species, it is often divided into two main categories; namely, avoidance/flight and immobility. To these, different researchers have added different categories, such as threat display and attack, protective responses (including startle and looming responses), defensive burying, and social responses (including alarm vocalizations and submission). Finally, immobility is often divided into freezing and tonic immobility.
  
  The decision as to which particular fear behavior to perform is determined by the level of fear as well as the specific context, such as environmental characteristics (escape route present, distance to refuge), the presence of a discrete and localized threat, the distance between threat and subject, threat characteristics (speed, size, directness of approach), the characteristics of the subject under threat (size, physical condition, speed, degree of crypsis, protective morphological structures), social conditions (group size), and the amount of experience with the type of the threat.