Final answer:
Marsupials are the animal type found only in Australia due to the continent's long geographic isolation, highlighting evolution's role in species distribution. Examples include kangaroos and koalas, which evolved into unique species on the isolated continent.
Step-by-step explanation:
The animal type found only in Australia that demonstrates evolution as a factor in the geographic distribution of species are marsupials. Marsupials such as kangaroos, koalas, and platypuses are endemic to Australia, meaning they are found nowhere else in the world. This is due to Australia’s long period of isolation, which has allowed these species to diverge evolutionarily into unique forms that reflect their adaptation to the local environment. The marsupials, along with other endemic species, showcase the influence of biogeographic isolation and evolutionary processes on species distribution.
Marsupials stand as a vivid example of evolutionary diversification in response to geologic changes such as the breakup of the supercontinents like Pangaea and Gondwana. This has led to distinctive flora and fauna on continents that have been separated for millions of years. Australia's high level of endemism among plant and mammal species illustrates the profound biogeographic patterns explained by evolutionary theory and the movement of tectonic plates.