Using PageRank to Prevent Extinction
In the expansive network that is the Internet, there are websites that are more important than others. In order to determine this level of importance, Google uses the PageRank algorithm, which increases the importance of sites that are linked to other important sites. By doing this, Google determines which sites it should display in response to a search.
While this algorithm is useful for websites, it can also be applied to other types of networks. The Internet can be thought of as a large web, so other, similarly structured networks would also be able to use the algorithm. One of these such networks is the food web. This directed web includes animals or plants as nodes, with links connecting each pair in which one consumes the other. In this example, the importance of each organism does not refer to the validity and usefulness of information it provides; instead it refers to the vitality of the organism to its ecosystem. An important animal in the ecosystem would consume other organisms, but would also have predators. In the web, these important animals would have several links connecting them to other animals in the web.
Because we can use the PageRank algorithm to determine the importance of a particular species to its ecosystem, we can then use this information to help protect the most important species, as we know that they are the most vital in helping to sustain the ecosystem. Additionally, we can determine which species are most likely to go extinct next, because they will have the lowest importance. However, by using the information found by using PageRank, we can help to regulate the populations of the other species in the ecosystem, which would increase the importance of the species we are trying to help, and then as a result, decrease their chance of extinction.
https://www.wired.com/2009/09/googlefoodwebs/