Answer:
The evolution of the species might occur due to the change in the environmental conditions and the mutation in the organisms. The organism that can adapt in the environment will survive better.
The lizard species is present in the Ethiopian biogeographical region but now its two living species is in Neotropical biogeographic region and three species is in Australian biogeographic region. This might possible due to the fact that Neotropical and Australian lineages might have the common ancestor that were earlier originated in the Ethiopian region. The continental drift might have occur that breaks the Ethiopian biogeographical region and the species are present in the different island.