Aggressive Behavior

Farm Animal Behavior 0749-0720/87 $0.00 + .20 Aggressive Behavior David Fraser, Ph.D.,* and Jeffrey Rushen, Ph.D.t Lumpers and splitters are nowhere more divided than over what to include under the category \"aggression.\":j: Extreme lumpers define aggres- sion as any behavior causing, or intended to cause, harm to another organism, thus grouping everything from world wars to the swatting of flies under a common heading. Splitters argue that such a definition is a nonsensical conflation of unrelated activities; some even refuse to use the word \"aggression\" because of the confusion it has caused.17 In this article, we will concentrate on the major fighting-related activities of the most common food animals. CHANGING VIEWS OF AGGRESSIVE BEHAVIOR Over the past few decades, the scientific analysis of animal aggressive behavior has been undergoing a radical and much-needed overhaul that can be summarized, albeit too simply, in three stages. Up to about 1970, many studies contained the unstated assumption that aggression is a unitary phenomenon that can be \"measured\" by recording a single feature of agonistic behavior such as the frequency of attack or even as contrived a response as biting an inanimate object. 14 This assumption underlies a sizeable scientific literature representing a highly simplistic approach to the subject. This approach has been attacked repeat- edly for nearly two decades and cannot be but dead; however, the corpse seems reluctant to lie down. 17. 22, 76,82,83, 126 This article is contribution no. 1431, Animal Research Centre, Agriculture Canada, Ottawa *Research Scientist, Animal Research Centre, Agriculture Canada, Ottawa tVisiting Scientist, Animal Research Centre, Agriculture Canada, Ottawa :j:The term \"aggression\" implies attack, as distinct from defense. Many ethologists use the term \"agonistic\" behavior, which simply means \"combative\" and therefore includes attack, defense, threat, and any other activities related to fighting. This use of \"agonistic\" dates hack to 1660150 and is helpful in technical writing on behavior; however, the term confilses physiologists who have given it a completely different meaning. 169 Veterinary Clinics of North America: Food Animal Practice-Vol. 3, No.2, July 1987 285