Although the majority of ebulli share their fauna with other bubbles, most ebulli have a certain number of organisms that are endemic only to themselves. MacArthur and Wilson’s Theory of Island Biogeography (1) was first written to explain species richness on different islands in Earth Ebullus, basically stating that an island’s species diversity is influenced by its size and its proximity to the mainland. This was later expanded by considering each ebullus as its own island.

1^ MacArthur, Robert H.; Edward O. Wilson (1967). The Theory of Island Biogeography. Princeton, N.J.: Princeton University Press. pp. 203 pp. ISBN 978-0-691-08836-5.