? , - (Brandon & Davies, 1973). 75 000 (Goldstein & others, 1989). , . , . , , .
, . , 141 . , (Robert Buckhout, 1976) , 60% . , , .
, , . , . -
. ,
------------......------~~
, , , , , (Bothwell & others, 1980; Brigham, 1990; Luus & Wells, 1994). - , . , (Michael Leippe, 1994),, .
1972 . , , , , , (Wells & Murrav.1983).
404 ■ II.