EVERYDAY SCIENCE

Detailed explanation-1: -As expected, larger patches had greater mean bacterial richness; however, this increase in richness was not significant. In typical landscapes, larger areas tend to include greater habitat heterogeneity, which, up to a point, supports more different species (Rosenzweig 1995).

Detailed explanation-2: -Area increases diversity because a larger plot is likely to have more habitats, hence niches, to support a greater variety of species.

Detailed explanation-3: -What determines species richness in a habitat patch? Island biogeography theory argues that it is a combination of patch size and the distance of that patch to others – i.e. the smaller the patch, and the further from other patches, the fewer species. This theory has decades of support in the literature.

Detailed explanation-4: -Therefore, when combining patches into subsets of equal total area, subsets with many small patches often have more sampling points than subsets with few large patches. This would lead to a higher likelihood of finding a given species in the set of several small patches than in the few large patches.