Some concerned groups feel that zoos are cruelly exploitative while others argue they serve the vital function of protecting endangered animals. In my opinion, though zoos are inherently unnatural, their efforts are laudable overall.
Those activists who decry the existence of zoos often point out how animals live in the wild. A lion in the African Serengeti, one of the few remaining preserves for lions in their natural habitat, roams over miles of grassland, hunts for meals and competes with rival prides. This is how lions have lived for thousands of years and is the natural byproduct of a generational process of evolution. The same lion placed in a zoo paces a small cage, is tossed already dead meat to eat, and rarely has other lions to interact or mate with. The evidence for zoos as a cruel institution lies in the contrasting of a natural and unnatural lifestyle and turning proud beasts into scavengers.
Regardless, zoos are essential for the preservation and cultivation of endangered species. There are countless animals ranging from various big cats (lions, tigers, leopards, and other sub-species), to pandas, rhinoceros, gorillas, pangolins and many more that depend on zoos for protection and safe breeding grounds. These animals have been driven to the brink of extinction either by loss of habitat due to rampant development and climate change or hunted for their fur or alleged medicinal properties. Responsible zoos are tasked with breeding them in order to stabilise falling populations and then re-introducing them into the wild. Without these zoos, many species would likely already have gone extinct.
In conclusion, zoos are fundamentally artificial but also a net positive because of their conservation efforts. To ensure this remains the case, these refuges must be well-regulated and governments should enact complementary solutions such as anti-poaching laws.