In the 11th century, a chinese scientist named shen kuo was one of the first people to develop a theory of earth's changing landscape . from a number of observations, he concluded that some cliffs and other landforms are formed by the processes of erosion and deposition. about 800 years later, an american scientist named william morris davis developed his theory of the cycle of erosion, in which he reasoned that flowing rivers form and shape many landforms. the example described above suggests that