Answer:
The diffusion referred to in the question above is called Stimulus Diffusion.
This refers to the transmission of an idea or culture from it's original demography to another and then changes in the way it is being practised or is adopted in a different way in the new region.
Explanation:
In The Lorax, which is a children's book written by Dr Seuss and first published in the late nineteenth century. In the book, the author speaks to economic and industrial issues as it affects the environment.
The Onceler in the Lorax used to be an agent of environmental destruction and tells his tale from a point of regret. It is in the course of telling the story of how he masterminded the destruction of the environment in the valley that once contained a forest of Truffula trees and a range of animals that he mentions how his idea diffused into the valley.
Where he came from people wore Thneeds and they wore in around their necks. In the valley, they didn't. Nobody knew what a Thneed was. He relocated to the valley because of what he thought was a business opportunity: Demand for Thneeds. He then tries to sell the Thneed which was made out of the Truffula trees but the people of the valley were not interested.
After several attempts at sales of Thneed, he gives up and throws the Thneed away. Just then, it hits a girl who starts to wear it as a hat. Somehow, people take a liking to the Thneed as worn by the girl and they all rush to the Onceler to make one for them.
So in the above, narrative, we see a Stimulus Diffusion of an idea or culture. The Thneed was a new idea which got diffused into the culture of the people of the valley. Not only that, but they also changed the way the Thneed was being used where the Onceler came from.
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