The investigation that Melissa and Lydia chose required the use of science and geography. Much of geography focuses on the spatial relationships between things. Distribution of animals over the world can sometimes be explained by locations of mountain ranges or oceans. By understanding territorial boundaries we may understand why only a few individuals of a species live in a large area.
Maps are tools used by geographers to show spatial relationships.
GIS is a high-tech way for geographers to map spatial relationships. Melissa and Lydia could have used simple mapping to reveal relationships between communities and abiotic factors. For example, a map of tree canopy and shrubs may show that shrubs only grow in more open spaces. A map of soil permeability and grass density may show that grasses don't grow well in compacted soils. Both of these relationships could best be displayed on maps and could improve understanding about how abiotic and biotic factors affect communities.