Watson's ideas were adopted by experimental psychologists who were particularly interested in studying learning under laboratory conditions. Perhaps the best known exponent of this approach in its purest form was Fred Skinner who believed that behaviour was shaped by reward. Essentially reward leads to the repetition of a behaviour. The rat's behaviour is ' shaped ' by giving a pellet of food delivered via a button in Skinner's hand. These are behaviours that show little variability between members of the same species e.g. courtship displays in birds understanding the evolutionary pathway through which the genetic basis for the behaviour came about.
Many ethologists capture their observations on videotape or audio tape.
The female is led by the male to a nest he has constructed on the floor of the pond or stream. She may creep through the nest and spawn. The male then follows and fertilizes the eggs. He may chase the female away. The male stays by the nest periodically fanning the nest to drive water over it and oxygenate the eggs.