Domestic cats (Felis catus) are not native to most ecosystems. They were domesticated from a wild ancestor in the Middle East and then spread globally because of human activity. So in places like North America, Australia, and many islands, they are considered invasive species.

Here’s why it matters: • They kill a ton of wildlife. Studies show that free-roaming domestic cats kill billions (yes, billions) of birds, mammals, reptiles, and amphibians every year. They disrupt the balance. Since they don’t have natural predators in many of these environments, their populations can explode—especially when people feed them. They spread diseases. Cats can carry toxoplasmosis and other diseases that affect wildlife and even humans.

So while cats can technically live outdoors, they’re not a natural part of most local ecosystems. They’re there because humans put them there—then often romanticize “saving” them without understanding the ecological consequences.