Which of the following statements are correct about the impact of Darwin on Geographical Thought.

A. Davision Concept of cycle of erosion was inspired by the central idea in the Origin of Species regarding change in species through time.

B. Siddal stressed the need for physiological study to assess environmental effects on man.

C. The Davision geomorphology adopted the biological analogy of ageing to the development of landforms.

D. Fleure had focussed on the theme of natural selection and environmental influences.

Choose the correct answer from the options given below: