Explain why most parasites do not kill their host. Why is it in their own best interest to keep their host alive?

Usually, although parasites harm their hosts, it is in the parasite's best interest not to kill the host, because it relies on the host's body and body functions, such as digestion or blood circulation, to live. Some parasitic animals attack plants.

Explanation:

Parasitism is a type of consumer-resource interaction, but unlike predators, parasites, with the exception of parasitoids, are typically much smaller than their hosts, do not kill them, and often live in or on their hosts for an extended period.A parasite is an organism that lives in another organism, called the host, and often harms it. It depends on its host for survival. Without a host, a parasite cannot live, grow and multiply.Parasitic castrators partly or completely destroy their host's ability to reproduce, diverting the energy that would have gone into reproduction into host and parasite growth, sometimes causing gigantism in the host. It will not kill their hosts because host organisms are capable of surviving on its own and provides energy source to the parasite. Generally, if the host cell dies then the parasite will also die. Hence, the parasite will not kill the host cells.