* Predators: Predators, such as lions, tigers, and bears, kill other animals for food.
* Prey: Prey species, such as deer, rabbits, and fish, are killed by predators.
* Humans: Humans kill animals for various purposes, including food, clothing, and entertainment.
* Diseases: Diseases, such as rabies, distemper, and influenza, can kill animals.
* Accidents: Animals may be killed in accidents, such as being hit by cars, falling off cliffs, or drowning.
* Natural disasters: Natural disasters, such as hurricanes, floods, and wildfires, can kill animals.