Answer
According to the theory of island biogeography, it can be predicted that the fragmentation of forest would decrease the species richness.
Work Step by Step
When the incidence of forest fragmentation occurs, the species richness declines in the fragmented habitats. The mice occupy a broad ecological niche and can survive in most of the communities regardless of the habitat quality. The mice are the huge reservoirs of Borrelia burgdorferi bacteria. These bacteria are responsible for causing Lyme disease.
Thus, if the fragmentation occurs, the mice population will be divided into different fragments. This would, in turn, reduce the bacterial reservoir in the particular fragment.
