Two experiments are reported which investigated nature of recognition of natural objects. Stimuli materials were butterfly and bee photographs. Each five features of original pictures were changed to generate changed pictures. In Experiment 1, subjects were given the recognition memory task while the FRS (the sum of feature frequency in the stimuli set) and the component frequency of each feature were kept constant. The experiment was conducted about butterfly and bee pictures separately. Contribution of each feature affected recognition differently. In experiment 2, subjects were given the same task about butterfly pictures as in experiment 1 while similarity ratings between the original and the changed pictures were kept constant. Again contribution of each feature affected recognition differently. These findings suggest that contribution of each feature of natural objects towards recognition is different, and features which contributed highly towards recognition are ecologically meaningful.