Scientist: A small group of islands near Australia is inhabited by several species of iguana; closely related species also exist in the Americas, but nowhere else  The islands in question formed long after the fragmentation of Gondwana, the ancient supercontinent that included present-day South America and Australia
Thus, these species' progenitors must have rafted on floating debris across the Pacific Ocean from the Americas
The lineages of numerous plant and animal species found in Australia or in South America date back to a period prior to the fragmentation of Gondwana.