The Spread of Ideas in Time and Space
|Map from Peter Loud's Website|
Expansion diffusion: this happens when an idea, practice, good, etc spreads across an area like a fire across a field. In most cases the fire doesn't hop from place to place; it moves from areas that have already been burned. Expansion diffusion happens when one person tells another; thus it an idea eventually makes its way through an entire area or population. Hierarchical diffusion and contagious diffusion (below) are often described as subcategories of expansion diffusion.
Contagious diffusion: When we hear the word "contagious", we usually think of diseases, which are spread from person to person via various vectors. Contagious diffusion refers to the spread of an idea directly from person to person. The best example of contagious diffusion here I can think of is the spread of Facebook. When I first came here 5 years ago there were only two internet places in town, and they were both painfully slow. However, something happened between 2007 and 2010 that lead to the mushrooming of internet "cafes" in Sungai Penuh and surrounding towns (1). The proliferation of these establishments has made the internet available to a large segment of the population, and one of the first things people discover when the get online is Facebook. It's become quite common for people, even small children, to ask me for my Facebook address when they see me around town. Contagious diffusion is often likened to a wave of innovation passing through a region; in this case the internet and Facebook would definitely fit the bill.
|Map from here.|
Other barriers are reflectors which alter the course of diffusion processes. One of the classic examples of a reflection barrier is the city of Chicago and Lake Michigan. Like all growing cities, over the past century and a half Chicago has expanded its borders. However, since people can't live on water, the presence of the large lake has caused the city's expansion to move around the lake. Have a look at the map and you'll get the idea. In Kerinci valley Kerinci Seblat National Park functions as a reflecting barrier. We can see this in the way that villages have expanded in certain parts of the valley. Instead of opening up new land inside the park (2), village expansion has tended to follow the fringe of the park.
Some barriers act as filters, letting some things spread but slowing or completely stopping other things. Political boundaries are a good example of this. It's difficult to completely seal off a border; for instance you can't completely shut out communication transmitted through the air, but you can stop the flow of goods and people over land. And even when borders are very permeable, sometimes other factors, like language, slow the process of diffusion. There are also enabling factors, like technology. One good example of this is cellular towers. Handphones are pretty much useless if you can't get a signal, and you can't get a signal if you are too far from the tower. The construction of cell towers in nearly every corner of the valley has enabled the rapid spread of handphones, and now nearly everyone has one. You can see another example of an enabling technology in the picture to the right. I've already mentioned the notion of "distance decay"; in the case of frozen or perishable goods this actually takes a literally meaning. The advent of freezers in the minimarts of Sungai Penuh has allowed merchants to sell frozen goods, like "chicken" nuggets. According to my tiger-chasing buddy, who has lived here for nearly 20 years, these ice boxes are really starting to change the diet here, for better or worse.
Thus we can see how the geography of an area is related to the rate at which new ideas are introduced. For a long time the mountains functioned as a barrier protecting the people of Kerinci valley, but now the mountains have become an obstacle, limiting the rate at which new goods come to the people of Kerinci. As we've seen in previous posts, this is also related to conservation, as the national park which surrounds the valley has become a barrier as well since its protected status prevents the construction of new roads, which would presumably increase the rate of diffusion because they would make it easier to access the valley. For my part I'm eagerly awaiting the diffusion of Pizza Hut to the valley, as the one in Padang insists that my house is outside their delivery radius, and so they refuse to have a driver make the seven-hour trip to bring me a cheese-stuffed double pepperoni.
(1) I'm referring to "warnets", which are shacks that have a bunch of computers hooked up to the internet. Generally the connection is relatively fast, and you pay 20-40 cents an hour to use the internet.
(2) As we know from previous posts, the existence of the park certainly hasn't stopped illegal encroachment and cultivation, but it definitely changes the predominant direction of expansion.