Would All Domesticated and Farmed Animals Die Off If Humans Suddenly Disappear?

The idea of what would happen if humans were to suddenly disappear has fascinated scientists, historians, and general audiences alike. A notable example comes from the History Channel's documentary Life After People: Animals, which explores the potential fate of domesticated and farmed animals. Would they all perish, or adapt and thrive in the absence of human intervention?

Escaping the Domesticated Life

With the absence of humans, most domesticated animals would face significant challenges and die-offs. Many are specifically indigenous to and dependent on human settlements, and would struggle to adapt to the wild. Those that are smarter and more adaptable could survive and even multiply in their natural habitats.

For instance, cattle and swine, which have been profoundly modified by human selection over generations, would likely revert to more wild forms within a few generations. We see evidence of this in the offspring of escaped farm animals, where traits begin to shift away from their original domesticated states.

The Survival of the Fittest

Different types of domesticated animals have varying survival chances:

Small breeds of dogs: These are typically vulnerable, as larger dogs would consume them. However, larger and strong breeds such as huskies and beyond might adapt and blend into local canines. Cats: Adaptable and resilient, domestic cats would likely go feral and then further adapt to a wild lifestyle, similar to feral cats today. Feral Hogs: Already a significant issue in both Europe and North America, feral pigs are less of a concern, as they are already well-adapted to survive without human intervention. Goats: Highly adaptable and resilient, goats are expected to survive the transition. Sheep: It's less certain as domestic sheep would struggle to survive with bighorns. Cattle: As large and potentially aggressive animals, cattle have a good chance of survival, especially when it comes to dealing with an angry bull. Chickens: Predation and natural selection would likely render them extinct. Domestic Turkeys: Given their significant breeding differences from wild turkeys, they are unlikely to survive in the wild. Horses: Survive well in the wild, akin to their numerous wild counterparts today. Smaller Pets: Rodents like gerbils, hamsters, and guinea pigs would not survive without human intervention. Rabbits: Highly prolific and adaptable, rabbits could still survive the inevitable waves of predation.

Evolution in Reverse

Over centuries, humans have had a profound impact on the evolution of domesticated plants and animals. Today, we cultivate plants that scatter seeds over extended periods, while animals like sheep and goats are bred for year-round breeding. Through domestication, we have essentially reversed thousands of years of natural selection. In the absence of human intervention, these artificially selected traits would gradually revert.

Corn, for example, would revert to its natural state, dropping seeds at random rather than all at once. Domesticated animals, both for plants and animals, would face a similar fate. Within a generation, these species would face significant changes, with those outside of human agricultural systems surviving and adapting.

While the immediate aftermath would be a die-off of many domesticated species, those that escape would face natural selection, transforming back into their wild counterparts over time. This process, while gradual, would eventually see the return of wild traits, effectively reversing centuries of domestication.