Wild animals have captured human interest for hundreds of thousands of years, but the formal study of wild animals dates back to 4th-century Greece. The Greeks were among the first to collect wild animals for study, and Aristotle’s Classification of Species is considered one of his greatest contributions to the history of biology. This work marked the first attempt to classify animals based on their behaviors and, most importantly, their physiological similarities and differences.
European thinkers from the 17th to 19th centuries, including John Ray, Charles Darwin, and Charles LeRoy, were pioneers in promoting long-term observation of animals in their natural habitats. These scholars recognized the complexity and apparent purposefulness of animal behavior, and understood that long-term observation was the only way to obtain accurate and new information.
Wildlife conservation and management became formally recognized as a distinct discipline in the 1930s, and now there are nearly 19,000 employed Zoologist and Wildlife Biologist in the United States today.
Brueghel, J.(1616)Studies of animals. Wikiart.
https://www.wikiart.org/en/jan-brueghel-the-elder/studies-of-animals-donkeys-cats-and-monkeys