Abstract
1 The effects of a ‘minor’ tranquillizer (chlordiazepoxide) on the social behaviour of male golden hamsters were investigated. 2 Thirty-six hamsters were divided into pairs. Each pair was placed in an arena measuring 1 m2; under these conditions the hamsters fought, but once a winner and loser emerged the relationship between the two animals became stabilized. The influence of 50 mg/kg chlordiazepoxide on this stable relationship was investigated and compared with normal behaviour in the arena. 3 Under the influence of chlordiazepoxide, hamsters showed a significant reduction in ‘aggression’, ‘defensive fighting’ and an increase in ‘investigation’. 4 When the data for winners and losers were analysed independently, the drug was seen to influence losers more than winners. 5 It is postulated that the primary influence of chlordiazepoxide is to reduce fear and as a result ‘investigation’ is probably affected indirectly as a behaviour pattern suppressed in an individual showing fear of its opponent.