विकास का 'शीर्षगामी' (सेफालो-कॉडल) सिद्धांत यह सुझाव देता है कि विकास अग्रसर होता है:

Which of the following is NOT considered a principle of development?

'Every species, whether animal or human, follows a pattern of development typical of its species.' Which psychologist formulated this principle?