Why did zoos add reptile houses, aviaries, and insectaries during the 1800s?

During the mid-19th century, zoos were increasingly established around the world, largely modeled after the London Zoo. These facilities were intended to provide "genteel amusement and edification" for the public.1

To move beyond the mere spectacle of showcasing large, intimidating animals, zoos began adding reptile houses, aviaries, and insectaries. These additions allowed institutions to diversify their collections and offer a broader educational experience for visitors.1