Wind because its not mechanically eroding them..
Answer:
25% chance for purple flowers 75% chance for white flowers.
Explanation: The big letter is the dominant gene and that means that it will be what ever the dominant gene says. (unless both are recessive like with the "ww" purple flowers)
The expression of genes in an organism can be influenced by the environment, adding the external world in which the organism is or where it develops, as well as the organism's internal world, which includes such factors as its hormones and metabolism.