Final answer:
The example of the ostrich, emu, and rhea diverging into separate species due to geographical separation after the breakup of Gondwana supports Charles Darwin's theory of evolution.
Step-by-step explanation:
The case of the ostrich, emu, and rhea, who are large flightless birds found on different continents, yet sharing a common ancestor, supports Charles Darwin's theory of evolution. According to Darwin's concept of allopatric speciation, when a group of animals is geographically separated, they can evolve into distinct species over time due to the lack of gene flow between the populations. With the breakup of the ancient landmass Gondwana, the ancestors of these birds were isolated on the newly formed continents of Africa, Australia, and South America, leading to the evolutionary divergence that resulted in the species we see today.