Final answer:
Alfred Wegener is credited with the first classical definition of worldwide zoogeographical regions, influenced by his theory of continental drift and the concept of the former supercontinent Pangaea.
Step-by-step explanation:
The person credited with the first classical definition of the world zoogeographical regions is Alfred Wegener. Wegener, known for his scientific theory of continental drift, was pivotal in explaining the geographic distribution of organisms across the planet. His recognition of the similarities in fossils and living species on different continents was instrumental in proposing the past existence of a supercontinent named Pangaea, which later broke into the continents we know today.
Wegener's theories went beyond simple observation, as he amassed data over several years to support the idea that the continents were previously connected. Biogeography, which is the study of the distribution of species and ecosystems in geographic space and through geological time, owes much to Wegener's early 20th-century work. His insights helped to explain why distinct floras and faunas are found in various continents formed from the former supercontinent Gondwana, such as Australia, southern Africa, and South America.